/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package android.os;

import android.animation.ValueAnimator;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.TestApi;
import android.app.ActivityManager;
import android.app.ActivityThread;
import android.app.IActivityManager;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.content.pm.ApplicationInfo;
import android.net.TrafficStats;
import android.net.Uri;
import android.os.strictmode.CleartextNetworkViolation;
import android.os.strictmode.ContentUriWithoutPermissionViolation;
import android.os.strictmode.CustomViolation;
import android.os.strictmode.DiskReadViolation;
import android.os.strictmode.DiskWriteViolation;
import android.os.strictmode.FileUriExposedViolation;
import android.os.strictmode.InstanceCountViolation;
import android.os.strictmode.IntentReceiverLeakedViolation;
import android.os.strictmode.LeakedClosableViolation;
import android.os.strictmode.NetworkViolation;
import android.os.strictmode.NonSdkApiUsedViolation;
import android.os.strictmode.ResourceMismatchViolation;
import android.os.strictmode.ServiceConnectionLeakedViolation;
import android.os.strictmode.SqliteObjectLeakedViolation;
import android.os.strictmode.UnbufferedIoViolation;
import android.os.strictmode.UntaggedSocketViolation;
import android.os.strictmode.Violation;
import android.os.strictmode.WebViewMethodCalledOnWrongThreadViolation;
import android.util.ArrayMap;
import android.util.Log;
import android.util.Printer;
import android.util.Singleton;
import android.util.Slog;
import android.view.IWindowManager;

import com.android.internal.annotations.GuardedBy;
import com.android.internal.os.BackgroundThread;
import com.android.internal.os.RuntimeInit;
import com.android.internal.util.FastPrintWriter;
import com.android.internal.util.HexDump;

import dalvik.system.BlockGuard;
import dalvik.system.CloseGuard;
import dalvik.system.VMDebug;
import dalvik.system.VMRuntime;

import java.io.PrintWriter;
import java.io.StringWriter;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Deque;
import java.util.HashMap;
import java.util.concurrent.Executor;
import java.util.concurrent.RejectedExecutionException;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.Consumer;

StrictMode is a developer tool which detects things you might be doing by accident and brings
them to your attention so you can fix them.
StrictMode is most commonly used to catch accidental disk or network access on the
application's main thread, where UI operations are received and animations take place. Keeping
disk and network operations off the main thread makes for much smoother, more responsive
applications. By keeping your application's main thread responsive, you also prevent ANR dialogs from being shown to
users.
Note that even though an Android device's disk is often on flash memory, many
devices run a filesystem on top of that memory with very limited concurrency. It's often the case
that almost all disk accesses are fast, but may in individual cases be dramatically slower when
certain I/O is happening in the background from other processes. If possible, it's best to assume
that such things are not fast.
Example code to enable from early in your Application, Activity, or other application component's Application.onCreate method: 
public void onCreate() { if (DEVELOPER_MODE) { StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder() .detectDiskReads() .detectDiskWrites() .detectNetwork() // or .detectAll() for all detectable problems .penaltyLog() .build()); StrictMode.setVmPolicy(new StrictMode.VmPolicy.Builder() .detectLeakedSqlLiteObjects() .detectLeakedClosableObjects() .penaltyLog() .penaltyDeath() .build()); } super.onCreate(); } 
You can decide what should happen when a violation is detected. For example, using Builder.penaltyLog you can watch the output of adb logcat while you
use your application to see the violations as they happen.
If you find violations that you feel are problematic, there are a variety of tools to help solve them: threads, Handler, AsyncTask, IntentService, etc. But don't feel compelled to fix everything that StrictMode finds. In particular, many cases of disk access are often necessary during the normal activity lifecycle. Use StrictMode to find things you did by accident. Network requests on the UI thread are almost always a problem, though. 
StrictMode is not a security mechanism and is not guaranteed to find all disk or network accesses. While it does propagate its state across process boundaries when doing Binder calls, it's still ultimately a best effort mechanism. Notably, disk or network access from JNI calls won't necessarily trigger it. Future versions of Android may catch more (or fewer) operations, so you should never leave StrictMode enabled in applications distributed on Google Play. /**
 * StrictMode is a developer tool which detects things you might be doing by accident and brings
 * them to your attention so you can fix them.
 *
 * <p>StrictMode is most commonly used to catch accidental disk or network access on the
 * application's main thread, where UI operations are received and animations take place. Keeping
 * disk and network operations off the main thread makes for much smoother, more responsive
 * applications. By keeping your application's main thread responsive, you also prevent <a
 * href="{@docRoot}guide/practices/design/responsiveness.html">ANR dialogs</a> from being shown to
 * users.
 *
 * <p class="note">Note that even though an Android device's disk is often on flash memory, many
 * devices run a filesystem on top of that memory with very limited concurrency. It's often the case
 * that almost all disk accesses are fast, but may in individual cases be dramatically slower when
 * certain I/O is happening in the background from other processes. If possible, it's best to assume
 * that such things are not fast.
 *
 * <p>Example code to enable from early in your {@link android.app.Application}, {@link
 * android.app.Activity}, or other application component's {@link android.app.Application#onCreate}
 * method:
 *
 * <pre>
 * public void onCreate() {
 *     if (DEVELOPER_MODE) {
 *         StrictMode.setThreadPolicy(new {@link ThreadPolicy.Builder StrictMode.ThreadPolicy.Builder}()
 *                 .detectDiskReads()
 *                 .detectDiskWrites()
 *                 .detectNetwork()   // or .detectAll() for all detectable problems
 *                 .penaltyLog()
 *                 .build());
 *         StrictMode.setVmPolicy(new {@link VmPolicy.Builder StrictMode.VmPolicy.Builder}()
 *                 .detectLeakedSqlLiteObjects()
 *                 .detectLeakedClosableObjects()
 *                 .penaltyLog()
 *                 .penaltyDeath()
 *                 .build());
 *     }
 *     super.onCreate();
 * }
 * </pre>
 *
 * <p>You can decide what should happen when a violation is detected. For example, using {@link
 * ThreadPolicy.Builder#penaltyLog} you can watch the output of <code>adb logcat</code> while you
 * use your application to see the violations as they happen.
 *
 * <p>If you find violations that you feel are problematic, there are a variety of tools to help
 * solve them: threads, {@link android.os.Handler}, {@link android.os.AsyncTask}, {@link
 * android.app.IntentService}, etc. But don't feel compelled to fix everything that StrictMode
 * finds. In particular, many cases of disk access are often necessary during the normal activity
 * lifecycle. Use StrictMode to find things you did by accident. Network requests on the UI thread
 * are almost always a problem, though.
 *
 * <p class="note">StrictMode is not a security mechanism and is not guaranteed to find all disk or
 * network accesses. While it does propagate its state across process boundaries when doing {@link
 * android.os.Binder} calls, it's still ultimately a best effort mechanism. Notably, disk or network
 * access from JNI calls won't necessarily trigger it. Future versions of Android may catch more (or
 * fewer) operations, so you should never leave StrictMode enabled in applications distributed on
 * Google Play.
 */
public final class StrictMode {
    private static final String TAG = "StrictMode";
    private static final boolean LOG_V = Log.isLoggable(TAG, Log.VERBOSE);

    
Boolean system property to disable strict mode checks outright. Set this to 'true' to force
disable; 'false' has no effect on other enable/disable policy.
@hide
/**
     * Boolean system property to disable strict mode checks outright. Set this to 'true' to force
     * disable; 'false' has no effect on other enable/disable policy.
     *
     * @hide
     */
    public static final String DISABLE_PROPERTY = "persist.sys.strictmode.disable";

    
The boolean system property to control screen flashes on violations.
@hide
/**
     * The boolean system property to control screen flashes on violations.
     *
     * @hide
     */
    public static final String VISUAL_PROPERTY = "persist.sys.strictmode.visual";

    
Temporary property used to include DETECT_VM_CLEARTEXT_NETWORK in Builder.detectAll(). Apps can still always opt-into detection using Builder.detectCleartextNetwork(). /**
     * Temporary property used to include {@link #DETECT_VM_CLEARTEXT_NETWORK} in {@link
     * VmPolicy.Builder#detectAll()}. Apps can still always opt-into detection using {@link
     * VmPolicy.Builder#detectCleartextNetwork()}.
     */
    private static final String CLEARTEXT_PROPERTY = "persist.sys.strictmode.clear";

    
Quick feature-flag that can be used to disable the defaults provided by initThreadDefaults(ApplicationInfo) and initVmDefaults(ApplicationInfo). /**
     * Quick feature-flag that can be used to disable the defaults provided by {@link
     * #initThreadDefaults(ApplicationInfo)} and {@link #initVmDefaults(ApplicationInfo)}.
     */
    private static final boolean DISABLE = false;

    // Only apply VM penalties for the same violation at this interval.
    private static final long MIN_VM_INTERVAL_MS = 1000;

    // Only log a duplicate stack trace to the logs every second.
    private static final long MIN_LOG_INTERVAL_MS = 1000;

    // Only show an annoying dialog at most every 30 seconds
    private static final long MIN_DIALOG_INTERVAL_MS = 30000;

    // How many Span tags (e.g. animations) to report.
    private static final int MAX_SPAN_TAGS = 20;

    // How many offending stacks to keep track of (and time) per loop
    // of the Looper.
    private static final int MAX_OFFENSES_PER_LOOP = 10;

    // Byte 1: Thread-policy

    
@hide
/** @hide */
    @TestApi public static final int DETECT_DISK_WRITE = 0x01; // for ThreadPolicy

    
@hide
/** @hide */
    @TestApi public static final int DETECT_DISK_READ = 0x02; // for ThreadPolicy

    
@hide
/** @hide */
    @TestApi public static final int DETECT_NETWORK = 0x04; // for ThreadPolicy

    
For StrictMode.noteSlowCall()
@hide
/**
     * For StrictMode.noteSlowCall()
     *
     * @hide
     */
    @TestApi public static final int DETECT_CUSTOM = 0x08; // for ThreadPolicy

    
For StrictMode.noteResourceMismatch()
@hide
/**
     * For StrictMode.noteResourceMismatch()
     *
     * @hide
     */
    @TestApi public static final int DETECT_RESOURCE_MISMATCH = 0x10; // for ThreadPolicy

    
@hide
/** @hide */
    @TestApi public static final int DETECT_UNBUFFERED_IO = 0x20; // for ThreadPolicy

    private static final int ALL_THREAD_DETECT_BITS =
            DETECT_DISK_WRITE
                    | DETECT_DISK_READ
                    | DETECT_NETWORK
                    | DETECT_CUSTOM
                    | DETECT_RESOURCE_MISMATCH
                    | DETECT_UNBUFFERED_IO;

    // Byte 2: Process-policy

    
Note, a "VM_" bit, not thread.
@hide
/**
     * Note, a "VM_" bit, not thread.
     *
     * @hide
     */
    @TestApi public static final int DETECT_VM_CURSOR_LEAKS = 0x01 << 8; // for VmPolicy

    
Note, a "VM_" bit, not thread.
@hide
/**
     * Note, a "VM_" bit, not thread.
     *
     * @hide
     */
    @TestApi public static final int DETECT_VM_CLOSABLE_LEAKS = 0x02 << 8; // for VmPolicy

    
Note, a "VM_" bit, not thread.
@hide
/**
     * Note, a "VM_" bit, not thread.
     *
     * @hide
     */
    @TestApi public static final int DETECT_VM_ACTIVITY_LEAKS = 0x04 << 8; // for VmPolicy

    
@hide
/** @hide */
    @TestApi public static final int DETECT_VM_INSTANCE_LEAKS = 0x08 << 8; // for VmPolicy

    
@hide
/** @hide */
    @TestApi public static final int DETECT_VM_REGISTRATION_LEAKS = 0x10 << 8; // for VmPolicy

    
@hide
/** @hide */
    @TestApi public static final int DETECT_VM_FILE_URI_EXPOSURE = 0x20 << 8; // for VmPolicy

    
@hide
/** @hide */
    @TestApi public static final int DETECT_VM_CLEARTEXT_NETWORK = 0x40 << 8; // for VmPolicy

    
@hide
/** @hide */
    @TestApi
    public static final int DETECT_VM_CONTENT_URI_WITHOUT_PERMISSION = 0x80 << 8; // for VmPolicy

    
@hide
/** @hide */
    @TestApi public static final int DETECT_VM_UNTAGGED_SOCKET = 0x80 << 24; // for VmPolicy

    
@hide
/** @hide */
    @TestApi public static final int DETECT_VM_NON_SDK_API_USAGE = 0x40 << 24; // for VmPolicy

    private static final int ALL_VM_DETECT_BITS =
            DETECT_VM_CURSOR_LEAKS
                    | DETECT_VM_CLOSABLE_LEAKS
                    | DETECT_VM_ACTIVITY_LEAKS
                    | DETECT_VM_INSTANCE_LEAKS
                    | DETECT_VM_REGISTRATION_LEAKS
                    | DETECT_VM_FILE_URI_EXPOSURE
                    | DETECT_VM_CLEARTEXT_NETWORK
                    | DETECT_VM_CONTENT_URI_WITHOUT_PERMISSION
                    | DETECT_VM_UNTAGGED_SOCKET
                    | DETECT_VM_NON_SDK_API_USAGE;


    // Byte 3: Penalty

    
{@hide} /** {@hide} */
    public static final int PENALTY_LOG = 0x01 << 16; // normal android.util.Log
    
{@hide} /** {@hide} */
    public static final int PENALTY_DIALOG = 0x02 << 16;
    
{@hide} /** {@hide} */
    public static final int PENALTY_DEATH = 0x04 << 16;
    
{@hide} /** {@hide} */
    public static final int PENALTY_FLASH = 0x10 << 16;
    
{@hide} /** {@hide} */
    public static final int PENALTY_DROPBOX = 0x20 << 16;

    
Non-public penalty mode which overrides all the other penalty bits and signals that we're in
a Binder call and we should ignore the other penalty bits and instead serialize back all our
offending stack traces to the caller to ultimately handle in the originating process.
This must be kept in sync with the constant in libs/binder/Parcel.cpp
@hide
/**
     * Non-public penalty mode which overrides all the other penalty bits and signals that we're in
     * a Binder call and we should ignore the other penalty bits and instead serialize back all our
     * offending stack traces to the caller to ultimately handle in the originating process.
     *
     * <p>This must be kept in sync with the constant in libs/binder/Parcel.cpp
     *
     * @hide
     */
    public static final int PENALTY_GATHER = 0x40 << 16;

    // Byte 4: Special cases

    
Death when network traffic is detected on main thread.
@hide
/**
     * Death when network traffic is detected on main thread.
     *
     * @hide
     */
    public static final int PENALTY_DEATH_ON_NETWORK = 0x01 << 24;

    
Death when cleartext network traffic is detected.
@hide
/**
     * Death when cleartext network traffic is detected.
     *
     * @hide
     */
    public static final int PENALTY_DEATH_ON_CLEARTEXT_NETWORK = 0x02 << 24;

    
Death when file exposure is detected.
@hide
/**
     * Death when file exposure is detected.
     *
     * @hide
     */
    public static final int PENALTY_DEATH_ON_FILE_URI_EXPOSURE = 0x04 << 24;

    // CAUTION: we started stealing the top bits of Byte 4 for VM above

    
Mask of all the penalty bits valid for thread policies. /** Mask of all the penalty bits valid for thread policies. */
    private static final int THREAD_PENALTY_MASK =
            PENALTY_LOG
                    | PENALTY_DIALOG
                    | PENALTY_DEATH
                    | PENALTY_DROPBOX
                    | PENALTY_GATHER
                    | PENALTY_DEATH_ON_NETWORK
                    | PENALTY_FLASH;

    
Mask of all the penalty bits valid for VM policies. /** Mask of all the penalty bits valid for VM policies. */
    private static final int VM_PENALTY_MASK =
            PENALTY_LOG
                    | PENALTY_DEATH
                    | PENALTY_DROPBOX
                    | PENALTY_DEATH_ON_CLEARTEXT_NETWORK
                    | PENALTY_DEATH_ON_FILE_URI_EXPOSURE;

    
{@hide} /** {@hide} */
    public static final int NETWORK_POLICY_ACCEPT = 0;
    
{@hide} /** {@hide} */
    public static final int NETWORK_POLICY_LOG = 1;
    
{@hide} /** {@hide} */
    public static final int NETWORK_POLICY_REJECT = 2;

    // TODO: wrap in some ImmutableHashMap thing.
    // Note: must be before static initialization of sVmPolicy.
    private static final HashMap<Class, Integer> EMPTY_CLASS_LIMIT_MAP =
            new HashMap<Class, Integer>();

    
The current VmPolicy in effect. /** The current VmPolicy in effect. */
    private static volatile VmPolicy sVmPolicy = VmPolicy.LAX;

    
{@hide} /** {@hide} */
    @TestApi
    public interface ViolationLogger {

        
Called when penaltyLog is enabled and a violation needs logging. /** Called when penaltyLog is enabled and a violation needs logging. */
        void log(ViolationInfo info);
    }

    private static final ViolationLogger LOGCAT_LOGGER =
            info -> {
                String msg;
                if (info.durationMillis != -1) {
                    msg = "StrictMode policy violation; ~duration=" + info.durationMillis + " ms:";
                } else {
                    msg = "StrictMode policy violation:";
                }
                Log.d(TAG, msg + " " + info.getStackTrace());
            };

    private static volatile ViolationLogger sLogger = LOGCAT_LOGGER;

    private static final ThreadLocal<OnThreadViolationListener> sThreadViolationListener =
            new ThreadLocal<>();
    private static final ThreadLocal<Executor> sThreadViolationExecutor = new ThreadLocal<>();

    
When #Builder.penaltyListener is enabled, the listener is called on the provided executor when a Thread violation occurs. /**
     * When #{@link ThreadPolicy.Builder#penaltyListener} is enabled, the listener is called on the
     * provided executor when a Thread violation occurs.
     */
    public interface OnThreadViolationListener {
        
Called on a thread policy violation. /** Called on a thread policy violation. */
        void onThreadViolation(Violation v);
    }

    
When #Builder.penaltyListener is enabled, the listener is called on the provided executor when a VM violation occurs. /**
     * When #{@link VmPolicy.Builder#penaltyListener} is enabled, the listener is called on the
     * provided executor when a VM violation occurs.
     */
    public interface OnVmViolationListener {
        
Called on a VM policy violation. /** Called on a VM policy violation. */
        void onVmViolation(Violation v);
    }

    
{@hide} /** {@hide} */
    @TestApi
    public static void setViolationLogger(ViolationLogger listener) {
        if (listener == null) {
            listener = LOGCAT_LOGGER;
        }
        sLogger = listener;
    }

    
The number of threads trying to do an async dropbox write. Just to limit ourselves out of
paranoia.
/**
     * The number of threads trying to do an async dropbox write. Just to limit ourselves out of
     * paranoia.
     */
    private static final AtomicInteger sDropboxCallsInFlight = new AtomicInteger(0);

    
Callback supplied to dalvik / libcore to get informed of usages of java API that are not
a part of the public SDK.
/**
     * Callback supplied to dalvik / libcore to get informed of usages of java API that are not
     * a part of the public SDK.
     */
    private static final Consumer<String> sNonSdkApiUsageConsumer =
            message -> onVmPolicyViolation(new NonSdkApiUsedViolation(message));

    private StrictMode() {}

    
StrictMode policy applied to a certain thread. 
The policy is enabled by setThreadPolicy. The current policy can be retrieved with StrictMode.getThreadPolicy. 
Note that multiple penalties may be provided and they're run in order from least to most
severe (logging before process death, for example). There's currently no mechanism to choose
different penalties for different detected actions.
/**
     * {@link StrictMode} policy applied to a certain thread.
     *
     * <p>The policy is enabled by {@link #setThreadPolicy}. The current policy can be retrieved
     * with {@link #getThreadPolicy}.
     *
     * <p>Note that multiple penalties may be provided and they're run in order from least to most
     * severe (logging before process death, for example). There's currently no mechanism to choose
     * different penalties for different detected actions.
     */
    public static final class ThreadPolicy {
        
The default, lax policy which doesn't catch anything. /** The default, lax policy which doesn't catch anything. */
        public static final ThreadPolicy LAX = new ThreadPolicy(0, null, null);

        final int mask;
        final OnThreadViolationListener mListener;
        final Executor mCallbackExecutor;

        private ThreadPolicy(int mask, OnThreadViolationListener listener, Executor executor) {
            this.mask = mask;
            mListener = listener;
            mCallbackExecutor = executor;
        }

        @Override
        public String toString() {
            return "[StrictMode.ThreadPolicy; mask=" + mask + "]";
        }

        
Creates ThreadPolicy instances. Methods whose names start with detect specify what problems we should look for. Methods whose names start with penalty specify what we should do when we detect a problem. 
You can call as many detect and penalty methods as you like. Currently order is insignificant: all penalties apply to all detected problems. 
For example, detect everything and log anything that's found:
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
    .detectAll()
    .penaltyLog()
    .build();
StrictMode.setThreadPolicy(policy);

/**
         * Creates {@link ThreadPolicy} instances. Methods whose names start with {@code detect}
         * specify what problems we should look for. Methods whose names start with {@code penalty}
         * specify what we should do when we detect a problem.
         *
         * <p>You can call as many {@code detect} and {@code penalty} methods as you like. Currently
         * order is insignificant: all penalties apply to all detected problems.
         *
         * <p>For example, detect everything and log anything that's found:
         *
         * <pre>
         * StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
         *     .detectAll()
         *     .penaltyLog()
         *     .build();
         * StrictMode.setThreadPolicy(policy);
         * </pre>
         */
        public static final class Builder {
            private int mMask = 0;
            private OnThreadViolationListener mListener;
            private Executor mExecutor;

            
Create a Builder that detects nothing and has no violations. (but note that build will default to enabling penaltyLog if no other penalties are specified) /**
             * Create a Builder that detects nothing and has no violations. (but note that {@link
             * #build} will default to enabling {@link #penaltyLog} if no other penalties are
             * specified)
             */
            public Builder() {
                mMask = 0;
            }

            
Initialize a Builder from an existing ThreadPolicy. /** Initialize a Builder from an existing ThreadPolicy. */
            public Builder(ThreadPolicy policy) {
                mMask = policy.mask;
                mListener = policy.mListener;
                mExecutor = policy.mCallbackExecutor;
            }

            
Detect everything that's potentially suspect.
As of the Gingerbread release this includes network and disk operations but will
likely expand in future releases.
/**
             * Detect everything that's potentially suspect.
             *
             * <p>As of the Gingerbread release this includes network and disk operations but will
             * likely expand in future releases.
             */
            public Builder detectAll() {
                detectDiskReads();
                detectDiskWrites();
                detectNetwork();

                final int targetSdk = VMRuntime.getRuntime().getTargetSdkVersion();
                if (targetSdk >= Build.VERSION_CODES.HONEYCOMB) {
                    detectCustomSlowCalls();
                }
                if (targetSdk >= Build.VERSION_CODES.M) {
                    detectResourceMismatches();
                }
                if (targetSdk >= Build.VERSION_CODES.O) {
                    detectUnbufferedIo();
                }
                return this;
            }

            
Disable the detection of everything. /** Disable the detection of everything. */
            public Builder permitAll() {
                return disable(ALL_THREAD_DETECT_BITS);
            }

            
Enable detection of network operations. /** Enable detection of network operations. */
            public Builder detectNetwork() {
                return enable(DETECT_NETWORK);
            }

            
Disable detection of network operations. /** Disable detection of network operations. */
            public Builder permitNetwork() {
                return disable(DETECT_NETWORK);
            }

            
Enable detection of disk reads. /** Enable detection of disk reads. */
            public Builder detectDiskReads() {
                return enable(DETECT_DISK_READ);
            }

            
Disable detection of disk reads. /** Disable detection of disk reads. */
            public Builder permitDiskReads() {
                return disable(DETECT_DISK_READ);
            }

            
Enable detection of slow calls. /** Enable detection of slow calls. */
            public Builder detectCustomSlowCalls() {
                return enable(DETECT_CUSTOM);
            }

            
Disable detection of slow calls. /** Disable detection of slow calls. */
            public Builder permitCustomSlowCalls() {
                return disable(DETECT_CUSTOM);
            }

            
Disable detection of mismatches between defined resource types and getter calls. /** Disable detection of mismatches between defined resource types and getter calls. */
            public Builder permitResourceMismatches() {
                return disable(DETECT_RESOURCE_MISMATCH);
            }

            
Detect unbuffered input/output operations. /** Detect unbuffered input/output operations. */
            public Builder detectUnbufferedIo() {
                return enable(DETECT_UNBUFFERED_IO);
            }

            
Disable detection of unbuffered input/output operations. /** Disable detection of unbuffered input/output operations. */
            public Builder permitUnbufferedIo() {
                return disable(DETECT_UNBUFFERED_IO);
            }

            
Enables detection of mismatches between defined resource types and getter calls.
This helps detect accidental type mismatches and potentially expensive type
conversions when obtaining typed resources.
For example, a strict mode violation would be thrown when calling TypedArray.getInt(int, int) on an index that contains a String-type resource. If the string value can be parsed as an integer, this method call will return a value without crashing; however, the developer should format the resource as an integer to avoid unnecessary type conversion. /**
             * Enables detection of mismatches between defined resource types and getter calls.
             *
             * <p>This helps detect accidental type mismatches and potentially expensive type
             * conversions when obtaining typed resources.
             *
             * <p>For example, a strict mode violation would be thrown when calling {@link
             * android.content.res.TypedArray#getInt(int, int)} on an index that contains a
             * String-type resource. If the string value can be parsed as an integer, this method
             * call will return a value without crashing; however, the developer should format the
             * resource as an integer to avoid unnecessary type conversion.
             */
            public Builder detectResourceMismatches() {
                return enable(DETECT_RESOURCE_MISMATCH);
            }

            
Enable detection of disk writes. /** Enable detection of disk writes. */
            public Builder detectDiskWrites() {
                return enable(DETECT_DISK_WRITE);
            }

            
Disable detection of disk writes. /** Disable detection of disk writes. */
            public Builder permitDiskWrites() {
                return disable(DETECT_DISK_WRITE);
            }

            
Show an annoying dialog to the developer on detected violations, rate-limited to be
only a little annoying.
/**
             * Show an annoying dialog to the developer on detected violations, rate-limited to be
             * only a little annoying.
             */
            public Builder penaltyDialog() {
                return enable(PENALTY_DIALOG);
            }

            
Crash the whole process on violation. This penalty runs at the end of all enabled
penalties so you'll still get see logging or other violations before the process
dies.
Unlike penaltyDeathOnNetwork, this applies to disk reads, disk writes, and network usage if their corresponding detect flags are set. /**
             * Crash the whole process on violation. This penalty runs at the end of all enabled
             * penalties so you'll still get see logging or other violations before the process
             * dies.
             *
             * <p>Unlike {@link #penaltyDeathOnNetwork}, this applies to disk reads, disk writes,
             * and network usage if their corresponding detect flags are set.
             */
            public Builder penaltyDeath() {
                return enable(PENALTY_DEATH);
            }

            
Crash the whole process on any network usage. Unlike penaltyDeath, this penalty runs before anything else. You must still have called detectNetwork to enable this. 
In the Honeycomb or later SDKs, this is on by default.
/**
             * Crash the whole process on any network usage. Unlike {@link #penaltyDeath}, this
             * penalty runs <em>before</em> anything else. You must still have called {@link
             * #detectNetwork} to enable this.
             *
             * <p>In the Honeycomb or later SDKs, this is on by default.
             */
            public Builder penaltyDeathOnNetwork() {
                return enable(PENALTY_DEATH_ON_NETWORK);
            }

            
Flash the screen during a violation. /** Flash the screen during a violation. */
            public Builder penaltyFlashScreen() {
                return enable(PENALTY_FLASH);
            }

            
Log detected violations to the system log. /** Log detected violations to the system log. */
            public Builder penaltyLog() {
                return enable(PENALTY_LOG);
            }

            
Enable detected violations log a stacktrace and timing data to the DropBox on policy violation. Intended mostly for platform integrators doing beta user field data collection. /**
             * Enable detected violations log a stacktrace and timing data to the {@link
             * android.os.DropBoxManager DropBox} on policy violation. Intended mostly for platform
             * integrators doing beta user field data collection.
             */
            public Builder penaltyDropBox() {
                return enable(PENALTY_DROPBOX);
            }

            
Call #OnThreadViolationListener.onThreadViolation(Violation) on specified executor every violation. /**
             * Call #{@link OnThreadViolationListener#onThreadViolation(Violation)} on specified
             * executor every violation.
             */
            public Builder penaltyListener(
                    @NonNull Executor executor, @NonNull OnThreadViolationListener listener) {
                if (executor == null) {
                    throw new NullPointerException("executor must not be null");
                }
                mListener = listener;
                mExecutor = executor;
                return this;
            }

            
@removed
/** @removed */
            public Builder penaltyListener(
                    @NonNull OnThreadViolationListener listener, @NonNull Executor executor) {
                return penaltyListener(executor, listener);
            }

            private Builder enable(int bit) {
                mMask |= bit;
                return this;
            }

            private Builder disable(int bit) {
                mMask &= ~bit;
                return this;
            }

            
Construct the ThreadPolicy instance.
Note: if no penalties are enabled before calling build, penaltyLog is implicitly set. /**
             * Construct the ThreadPolicy instance.
             *
             * <p>Note: if no penalties are enabled before calling <code>build</code>, {@link
             * #penaltyLog} is implicitly set.
             */
            public ThreadPolicy build() {
                // If there are detection bits set but no violation bits
                // set, enable simple logging.
                if (mListener == null
                        && mMask != 0
                        && (mMask
                                        & (PENALTY_DEATH
                                                | PENALTY_LOG
                                                | PENALTY_DROPBOX
                                                | PENALTY_DIALOG))
                                == 0) {
                    penaltyLog();
                }
                return new ThreadPolicy(mMask, mListener, mExecutor);
            }
        }
    }

    
StrictMode policy applied to all threads in the virtual machine's process. 
The policy is enabled by setVmPolicy. /**
     * {@link StrictMode} policy applied to all threads in the virtual machine's process.
     *
     * <p>The policy is enabled by {@link #setVmPolicy}.
     */
    public static final class VmPolicy {
        
The default, lax policy which doesn't catch anything. /** The default, lax policy which doesn't catch anything. */
        public static final VmPolicy LAX = new VmPolicy(0, EMPTY_CLASS_LIMIT_MAP, null, null);

        final int mask;
        final OnVmViolationListener mListener;
        final Executor mCallbackExecutor;

        // Map from class to max number of allowed instances in memory.
        final HashMap<Class, Integer> classInstanceLimit;

        private VmPolicy(
                int mask,
                HashMap<Class, Integer> classInstanceLimit,
                OnVmViolationListener listener,
                Executor executor) {
            if (classInstanceLimit == null) {
                throw new NullPointerException("classInstanceLimit == null");
            }
            this.mask = mask;
            this.classInstanceLimit = classInstanceLimit;
            mListener = listener;
            mCallbackExecutor = executor;
        }

        @Override
        public String toString() {
            return "[StrictMode.VmPolicy; mask=" + mask + "]";
        }

        
Creates VmPolicy instances. Methods whose names start with detect specify what problems we should look for. Methods whose names start with penalty specify what we should do when we detect a problem. 
You can call as many detect and penalty methods as you like. Currently order is insignificant: all penalties apply to all detected problems. 
For example, detect everything and log anything that's found:
StrictMode.VmPolicy policy = new StrictMode.VmPolicy.Builder()
    .detectAll()
    .penaltyLog()
    .build();
StrictMode.setVmPolicy(policy);

/**
         * Creates {@link VmPolicy} instances. Methods whose names start with {@code detect} specify
         * what problems we should look for. Methods whose names start with {@code penalty} specify
         * what we should do when we detect a problem.
         *
         * <p>You can call as many {@code detect} and {@code penalty} methods as you like. Currently
         * order is insignificant: all penalties apply to all detected problems.
         *
         * <p>For example, detect everything and log anything that's found:
         *
         * <pre>
         * StrictMode.VmPolicy policy = new StrictMode.VmPolicy.Builder()
         *     .detectAll()
         *     .penaltyLog()
         *     .build();
         * StrictMode.setVmPolicy(policy);
         * </pre>
         */
        public static final class Builder {
            private int mMask;
            private OnVmViolationListener mListener;
            private Executor mExecutor;

            private HashMap<Class, Integer> mClassInstanceLimit; // null until needed
            private boolean mClassInstanceLimitNeedCow = false; // need copy-on-write

            public Builder() {
                mMask = 0;
            }

            
Build upon an existing VmPolicy. /** Build upon an existing VmPolicy. */
            public Builder(VmPolicy base) {
                mMask = base.mask;
                mClassInstanceLimitNeedCow = true;
                mClassInstanceLimit = base.classInstanceLimit;
                mListener = base.mListener;
                mExecutor = base.mCallbackExecutor;
            }

            
Set an upper bound on how many instances of a class can be in memory at once. Helps
to prevent object leaks.
/**
             * Set an upper bound on how many instances of a class can be in memory at once. Helps
             * to prevent object leaks.
             */
            public Builder setClassInstanceLimit(Class klass, int instanceLimit) {
                if (klass == null) {
                    throw new NullPointerException("klass == null");
                }
                if (mClassInstanceLimitNeedCow) {
                    if (mClassInstanceLimit.containsKey(klass)
                            && mClassInstanceLimit.get(klass) == instanceLimit) {
                        // no-op; don't break COW
                        return this;
                    }
                    mClassInstanceLimitNeedCow = false;
                    mClassInstanceLimit = (HashMap<Class, Integer>) mClassInstanceLimit.clone();
                } else if (mClassInstanceLimit == null) {
                    mClassInstanceLimit = new HashMap<Class, Integer>();
                }
                mMask |= DETECT_VM_INSTANCE_LEAKS;
                mClassInstanceLimit.put(klass, instanceLimit);
                return this;
            }

            
Detect leaks of Activity subclasses. /** Detect leaks of {@link android.app.Activity} subclasses. */
            public Builder detectActivityLeaks() {
                return enable(DETECT_VM_ACTIVITY_LEAKS);
            }

            
@hide
/** @hide */
            public Builder permitActivityLeaks() {
                return disable(DETECT_VM_ACTIVITY_LEAKS);
            }

            
Detect reflective usage of APIs that are not part of the public Android SDK.
Note that any non-SDK APIs that this processes accesses before this detection is
enabled may not be detected. To ensure that all such API accesses are detected,
you should apply this policy as early as possible after process creation.
/**
             * Detect reflective usage of APIs that are not part of the public Android SDK.
             *
             * <p>Note that any non-SDK APIs that this processes accesses before this detection is
             * enabled may not be detected. To ensure that all such API accesses are detected,
             * you should apply this policy as early as possible after process creation.
             */
            public Builder detectNonSdkApiUsage() {
                return enable(DETECT_VM_NON_SDK_API_USAGE);
            }

            
Permit reflective usage of APIs that are not part of the public Android SDK. Note
that this only affects StrictMode, the underlying runtime may continue to restrict or warn on access to methods that are not part of the public SDK. /**
             * Permit reflective usage of APIs that are not part of the public Android SDK. Note
             * that this <b>only</b> affects {@code StrictMode}, the underlying runtime may
             * continue to restrict or warn on access to methods that are not part of the
             * public SDK.
             */
            public Builder permitNonSdkApiUsage() {
                return disable(DETECT_VM_NON_SDK_API_USAGE);
            }

            
Detect everything that's potentially suspect.
In the Honeycomb release this includes leaks of SQLite cursors, Activities, and
other closable objects but will likely expand in future releases.
/**
             * Detect everything that's potentially suspect.
             *
             * <p>In the Honeycomb release this includes leaks of SQLite cursors, Activities, and
             * other closable objects but will likely expand in future releases.
             */
            public Builder detectAll() {
                detectLeakedSqlLiteObjects();

                final int targetSdk = VMRuntime.getRuntime().getTargetSdkVersion();
                if (targetSdk >= Build.VERSION_CODES.HONEYCOMB) {
                    detectActivityLeaks();
                    detectLeakedClosableObjects();
                }
                if (targetSdk >= Build.VERSION_CODES.JELLY_BEAN) {
                    detectLeakedRegistrationObjects();
                }
                if (targetSdk >= Build.VERSION_CODES.JELLY_BEAN_MR2) {
                    detectFileUriExposure();
                }
                if (targetSdk >= Build.VERSION_CODES.M) {
                    // TODO: always add DETECT_VM_CLEARTEXT_NETWORK once we have
                    // facility for apps to mark sockets that should be ignored
                    if (SystemProperties.getBoolean(CLEARTEXT_PROPERTY, false)) {
                        detectCleartextNetwork();
                    }
                }
                if (targetSdk >= Build.VERSION_CODES.O) {
                    detectContentUriWithoutPermission();
                    detectUntaggedSockets();
                }

                // TODO: Decide whether to detect non SDK API usage beyond a certain API level.
                return this;
            }

            
Detect when an SQLiteCursor or other SQLite object is finalized without having been closed. 
You always want to explicitly close your SQLite cursors to avoid unnecessary
database contention and temporary memory leaks.
/**
             * Detect when an {@link android.database.sqlite.SQLiteCursor} or other SQLite object is
             * finalized without having been closed.
             *
             * <p>You always want to explicitly close your SQLite cursors to avoid unnecessary
             * database contention and temporary memory leaks.
             */
            public Builder detectLeakedSqlLiteObjects() {
                return enable(DETECT_VM_CURSOR_LEAKS);
            }

            
Detect when an Closeable or other object with an explicit termination method is finalized without having been closed. 
You always want to explicitly close such objects to avoid unnecessary resources
leaks.
/**
             * Detect when an {@link java.io.Closeable} or other object with an explicit termination
             * method is finalized without having been closed.
             *
             * <p>You always want to explicitly close such objects to avoid unnecessary resources
             * leaks.
             */
            public Builder detectLeakedClosableObjects() {
                return enable(DETECT_VM_CLOSABLE_LEAKS);
            }

            
Detect when a BroadcastReceiver or ServiceConnection is leaked during Context teardown. /**
             * Detect when a {@link BroadcastReceiver} or {@link ServiceConnection} is leaked during
             * {@link Context} teardown.
             */
            public Builder detectLeakedRegistrationObjects() {
                return enable(DETECT_VM_REGISTRATION_LEAKS);
            }

            
Detect when the calling application exposes a file:// Uri to another app. 
This exposure is discouraged since the receiving app may not have access to the shared path. For example, the receiving app may not have requested the READ_EXTERNAL_STORAGE.READ_EXTERNAL_STORAGE runtime permission, or the platform may be sharing the Uri across user profile boundaries. 
Instead, apps should use content:// Uris so the platform can extend temporary permission for the receiving app to access the resource. 
See Also:
FileProvider
Intent.FLAG_GRANT_READ_URI_PERMISSION/**
             * Detect when the calling application exposes a {@code file://} {@link android.net.Uri}
             * to another app.
             *
             * <p>This exposure is discouraged since the receiving app may not have access to the
             * shared path. For example, the receiving app may not have requested the {@link
             * android.Manifest.permission#READ_EXTERNAL_STORAGE} runtime permission, or the
             * platform may be sharing the {@link android.net.Uri} across user profile boundaries.
             *
             * <p>Instead, apps should use {@code content://} Uris so the platform can extend
             * temporary permission for the receiving app to access the resource.
             *
             * @see android.support.v4.content.FileProvider
             * @see Intent#FLAG_GRANT_READ_URI_PERMISSION
             */
            public Builder detectFileUriExposure() {
                return enable(DETECT_VM_FILE_URI_EXPOSURE);
            }

            
Detect any network traffic from the calling app which is not wrapped in SSL/TLS. This
can help you detect places that your app is inadvertently sending cleartext data
across the network.
Using penaltyDeath() or penaltyDeathOnCleartextNetwork() will block further traffic on that socket to prevent accidental data leakage, in addition to crashing your process. 
Using penaltyDropBox() will log the raw contents of the packet that triggered the violation. 
This inspects both IPv4/IPv6 and TCP/UDP network traffic, but it may be subject to
false positives, such as when STARTTLS protocols or HTTP proxies are used.
/**
             * Detect any network traffic from the calling app which is not wrapped in SSL/TLS. This
             * can help you detect places that your app is inadvertently sending cleartext data
             * across the network.
             *
             * <p>Using {@link #penaltyDeath()} or {@link #penaltyDeathOnCleartextNetwork()} will
             * block further traffic on that socket to prevent accidental data leakage, in addition
             * to crashing your process.
             *
             * <p>Using {@link #penaltyDropBox()} will log the raw contents of the packet that
             * triggered the violation.
             *
             * <p>This inspects both IPv4/IPv6 and TCP/UDP network traffic, but it may be subject to
             * false positives, such as when STARTTLS protocols or HTTP proxies are used.
             */
            public Builder detectCleartextNetwork() {
                return enable(DETECT_VM_CLEARTEXT_NETWORK);
            }

            
Detect when the calling application sends a content:// Uri to another app without setting Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_GRANT_WRITE_URI_PERMISSION. 
Forgetting to include one or more of these flags when sending an intent is
typically an app bug.
See Also:
Intent.FLAG_GRANT_READ_URI_PERMISSION
Intent.FLAG_GRANT_WRITE_URI_PERMISSION/**
             * Detect when the calling application sends a {@code content://} {@link
             * android.net.Uri} to another app without setting {@link
             * Intent#FLAG_GRANT_READ_URI_PERMISSION} or {@link
             * Intent#FLAG_GRANT_WRITE_URI_PERMISSION}.
             *
             * <p>Forgetting to include one or more of these flags when sending an intent is
             * typically an app bug.
             *
             * @see Intent#FLAG_GRANT_READ_URI_PERMISSION
             * @see Intent#FLAG_GRANT_WRITE_URI_PERMISSION
             */
            public Builder detectContentUriWithoutPermission() {
                return enable(DETECT_VM_CONTENT_URI_WITHOUT_PERMISSION);
            }

            
Detect any sockets in the calling app which have not been tagged using TrafficStats. Tagging sockets can help you investigate network usage inside your app, such as a narrowing down heavy usage to a specific library or component. 
This currently does not detect sockets created in native code.
See Also:
TrafficStats.setThreadStatsTag(int)
TrafficStats.tagSocket(Socket)
TrafficStats.tagDatagramSocket(DatagramSocket)/**
             * Detect any sockets in the calling app which have not been tagged using {@link
             * TrafficStats}. Tagging sockets can help you investigate network usage inside your
             * app, such as a narrowing down heavy usage to a specific library or component.
             *
             * <p>This currently does not detect sockets created in native code.
             *
             * @see TrafficStats#setThreadStatsTag(int)
             * @see TrafficStats#tagSocket(java.net.Socket)
             * @see TrafficStats#tagDatagramSocket(java.net.DatagramSocket)
             */
            public Builder detectUntaggedSockets() {
                return enable(DETECT_VM_UNTAGGED_SOCKET);
            }

            
@hide
/** @hide */
            public Builder permitUntaggedSockets() {
                return disable(DETECT_VM_UNTAGGED_SOCKET);
            }

            
Crashes the whole process on violation. This penalty runs at the end of all enabled
penalties so you'll still get your logging or other violations before the process
dies.
/**
             * Crashes the whole process on violation. This penalty runs at the end of all enabled
             * penalties so you'll still get your logging or other violations before the process
             * dies.
             */
            public Builder penaltyDeath() {
                return enable(PENALTY_DEATH);
            }

            
Crashes the whole process when cleartext network traffic is detected.
See Also:
detectCleartextNetwork()/**
             * Crashes the whole process when cleartext network traffic is detected.
             *
             * @see #detectCleartextNetwork()
             */
            public Builder penaltyDeathOnCleartextNetwork() {
                return enable(PENALTY_DEATH_ON_CLEARTEXT_NETWORK);
            }

            
Crashes the whole process when a file:// Uri is exposed beyond this app. 
See Also:
detectFileUriExposure()/**
             * Crashes the whole process when a {@code file://} {@link android.net.Uri} is exposed
             * beyond this app.
             *
             * @see #detectFileUriExposure()
             */
            public Builder penaltyDeathOnFileUriExposure() {
                return enable(PENALTY_DEATH_ON_FILE_URI_EXPOSURE);
            }

            
Log detected violations to the system log. /** Log detected violations to the system log. */
            public Builder penaltyLog() {
                return enable(PENALTY_LOG);
            }

            
Enable detected violations log a stacktrace and timing data to the DropBox on policy violation. Intended mostly for platform integrators doing beta user field data collection. /**
             * Enable detected violations log a stacktrace and timing data to the {@link
             * android.os.DropBoxManager DropBox} on policy violation. Intended mostly for platform
             * integrators doing beta user field data collection.
             */
            public Builder penaltyDropBox() {
                return enable(PENALTY_DROPBOX);
            }

            
Call #OnVmViolationListener.onVmViolation(Violation) on every violation. /**
             * Call #{@link OnVmViolationListener#onVmViolation(Violation)} on every violation.
             */
            public Builder penaltyListener(
                    @NonNull Executor executor, @NonNull OnVmViolationListener listener) {
                if (executor == null) {
                    throw new NullPointerException("executor must not be null");
                }
                mListener = listener;
                mExecutor = executor;
                return this;
            }

            
@removed
/** @removed */
            public Builder penaltyListener(
                    @NonNull OnVmViolationListener listener, @NonNull Executor executor) {
                return penaltyListener(executor, listener);
            }

            private Builder enable(int bit) {
                mMask |= bit;
                return this;
            }

            Builder disable(int bit) {
                mMask &= ~bit;
                return this;
            }

            
Construct the VmPolicy instance.
Note: if no penalties are enabled before calling build, penaltyLog is implicitly set. /**
             * Construct the VmPolicy instance.
             *
             * <p>Note: if no penalties are enabled before calling <code>build</code>, {@link
             * #penaltyLog} is implicitly set.
             */
            public VmPolicy build() {
                // If there are detection bits set but no violation bits
                // set, enable simple logging.
                if (mListener == null
                        && mMask != 0
                        && (mMask
                                        & (PENALTY_DEATH
                                                | PENALTY_LOG
                                                | PENALTY_DROPBOX
                                                | PENALTY_DIALOG))
                                == 0) {
                    penaltyLog();
                }
                return new VmPolicy(
                        mMask,
                        mClassInstanceLimit != null ? mClassInstanceLimit : EMPTY_CLASS_LIMIT_MAP,
                        mListener,
                        mExecutor);
            }
        }
    }

    
Log of strict mode violation stack traces that have occurred during a Binder call, to be
serialized back later to the caller via Parcel.writeNoException() (amusingly) where the
caller can choose how to react.
/**
     * Log of strict mode violation stack traces that have occurred during a Binder call, to be
     * serialized back later to the caller via Parcel.writeNoException() (amusingly) where the
     * caller can choose how to react.
     */
    private static final ThreadLocal<ArrayList<ViolationInfo>> gatheredViolations =
            new ThreadLocal<ArrayList<ViolationInfo>>() {
                @Override
                protected ArrayList<ViolationInfo> initialValue() {
                    // Starts null to avoid unnecessary allocations when
                    // checking whether there are any violations or not in
                    // hasGatheredViolations() below.
                    return null;
                }
            };

    
Sets the policy for what actions on the current thread should be detected, as well as the
penalty if such actions occur.
Internally this sets a thread-local variable which is propagated across cross-process IPC
calls, meaning you can catch violations when a system service or another process accesses the
disk or network on your behalf.
Params:
policy – the policy to put into place/**
     * Sets the policy for what actions on the current thread should be detected, as well as the
     * penalty if such actions occur.
     *
     * <p>Internally this sets a thread-local variable which is propagated across cross-process IPC
     * calls, meaning you can catch violations when a system service or another process accesses the
     * disk or network on your behalf.
     *
     * @param policy the policy to put into place
     */
    public static void setThreadPolicy(final ThreadPolicy policy) {
        setThreadPolicyMask(policy.mask);
        sThreadViolationListener.set(policy.mListener);
        sThreadViolationExecutor.set(policy.mCallbackExecutor);
    }

    
@hide
/** @hide */
    public static void setThreadPolicyMask(final int policyMask) {
        // In addition to the Java-level thread-local in Dalvik's
        // BlockGuard, we also need to keep a native thread-local in
        // Binder in order to propagate the value across Binder calls,
        // even across native-only processes.  The two are kept in
        // sync via the callback to onStrictModePolicyChange, below.
        setBlockGuardPolicy(policyMask);

        // And set the Android native version...
        Binder.setThreadStrictModePolicy(policyMask);
    }

    // Sets the policy in Dalvik/libcore (BlockGuard)
    private static void setBlockGuardPolicy(final int policyMask) {
        if (policyMask == 0) {
            BlockGuard.setThreadPolicy(BlockGuard.LAX_POLICY);
            return;
        }
        final BlockGuard.Policy policy = BlockGuard.getThreadPolicy();
        final AndroidBlockGuardPolicy androidPolicy;
        if (policy instanceof AndroidBlockGuardPolicy) {
            androidPolicy = (AndroidBlockGuardPolicy) policy;
        } else {
            androidPolicy = THREAD_ANDROID_POLICY.get();
            BlockGuard.setThreadPolicy(androidPolicy);
        }
        androidPolicy.setPolicyMask(policyMask);
    }

    // Sets up CloseGuard in Dalvik/libcore
    private static void setCloseGuardEnabled(boolean enabled) {
        if (!(CloseGuard.getReporter() instanceof AndroidCloseGuardReporter)) {
            CloseGuard.setReporter(new AndroidCloseGuardReporter());
        }
        CloseGuard.setEnabled(enabled);
    }

    
Returns the bitmask of the current thread's policy.
Returns:
the bitmask of all the DETECT_* and PENALTY_* bits currently enabled
@hide
/**
     * Returns the bitmask of the current thread's policy.
     *
     * @return the bitmask of all the DETECT_* and PENALTY_* bits currently enabled
     * @hide
     */
    public static int getThreadPolicyMask() {
        return BlockGuard.getThreadPolicy().getPolicyMask();
    }

    
Returns the current thread's policy. /** Returns the current thread's policy. */
    public static ThreadPolicy getThreadPolicy() {
        // TODO: this was a last minute Gingerbread API change (to
        // introduce VmPolicy cleanly) but this isn't particularly
        // optimal for users who might call this method often.  This
        // should be in a thread-local and not allocate on each call.
        return new ThreadPolicy(
                getThreadPolicyMask(),
                sThreadViolationListener.get(),
                sThreadViolationExecutor.get());
    }

    
A convenience wrapper that takes the current ThreadPolicy from getThreadPolicy, modifies it to permit both disk reads & writes, and sets the new policy with setThreadPolicy, returning the old policy so you can restore it at the end of a block. 
Returns:
the old policy, to be passed to setThreadPolicy to restore the policy at the end of a block/**
     * A convenience wrapper that takes the current {@link ThreadPolicy} from {@link
     * #getThreadPolicy}, modifies it to permit both disk reads &amp; writes, and sets the new
     * policy with {@link #setThreadPolicy}, returning the old policy so you can restore it at the
     * end of a block.
     *
     * @return the old policy, to be passed to {@link #setThreadPolicy} to restore the policy at the
     *     end of a block
     */
    public static ThreadPolicy allowThreadDiskWrites() {
        return new ThreadPolicy(
                allowThreadDiskWritesMask(),
                sThreadViolationListener.get(),
                sThreadViolationExecutor.get());
    }

    
@hide
/** @hide */
    public static int allowThreadDiskWritesMask() {
        int oldPolicyMask = getThreadPolicyMask();
        int newPolicyMask = oldPolicyMask & ~(DETECT_DISK_WRITE | DETECT_DISK_READ);
        if (newPolicyMask != oldPolicyMask) {
            setThreadPolicyMask(newPolicyMask);
        }
        return oldPolicyMask;
    }

    
A convenience wrapper that takes the current ThreadPolicy from getThreadPolicy, modifies it to permit disk reads, and sets the new policy with setThreadPolicy, returning the old policy so you can restore it at the end of a block. 
Returns:
the old policy, to be passed to setThreadPolicy to restore the policy./**
     * A convenience wrapper that takes the current {@link ThreadPolicy} from {@link
     * #getThreadPolicy}, modifies it to permit disk reads, and sets the new policy with {@link
     * #setThreadPolicy}, returning the old policy so you can restore it at the end of a block.
     *
     * @return the old policy, to be passed to setThreadPolicy to restore the policy.
     */
    public static ThreadPolicy allowThreadDiskReads() {
        return new ThreadPolicy(
                allowThreadDiskReadsMask(),
                sThreadViolationListener.get(),
                sThreadViolationExecutor.get());
    }

    
@hide
/** @hide */
    public static int allowThreadDiskReadsMask() {
        int oldPolicyMask = getThreadPolicyMask();
        int newPolicyMask = oldPolicyMask & ~(DETECT_DISK_READ);
        if (newPolicyMask != oldPolicyMask) {
            setThreadPolicyMask(newPolicyMask);
        }
        return oldPolicyMask;
    }

    private static ThreadPolicy allowThreadViolations() {
        ThreadPolicy oldPolicy = getThreadPolicy();
        setThreadPolicyMask(0);
        return oldPolicy;
    }

    private static VmPolicy allowVmViolations() {
        VmPolicy oldPolicy = getVmPolicy();
        sVmPolicy = VmPolicy.LAX;
        return oldPolicy;
    }

    
Determine if the given app is "bundled" as part of the system image. These bundled apps are developed in lock-step with the OS, and they aren't updated outside of an OTA, so we want to chase any StrictMode regressions by enabling detection when running on Build.IS_USERDEBUG or Build.IS_ENG builds. 
Unbundled apps included in the system image are expected to detect and triage their own StrictMode issues separate from the OS release process, which is why we don't enable them here. 
@hide
/**
     * Determine if the given app is "bundled" as part of the system image. These bundled apps are
     * developed in lock-step with the OS, and they aren't updated outside of an OTA, so we want to
     * chase any {@link StrictMode} regressions by enabling detection when running on {@link
     * Build#IS_USERDEBUG} or {@link Build#IS_ENG} builds.
     *
     * <p>Unbundled apps included in the system image are expected to detect and triage their own
     * {@link StrictMode} issues separate from the OS release process, which is why we don't enable
     * them here.
     *
     * @hide
     */
    public static boolean isBundledSystemApp(ApplicationInfo ai) {
        if (ai == null || ai.packageName == null) {
            // Probably system server
            return true;
        } else if (ai.isSystemApp()) {
            // Ignore unbundled apps living in the wrong namespace
            if (ai.packageName.equals("com.android.vending")
                    || ai.packageName.equals("com.android.chrome")) {
                return false;
            }

            // Ignore bundled apps that are way too spammy
            // STOPSHIP: burn this list down to zero
            if (ai.packageName.equals("com.android.phone")) {
                return false;
            }

            if (ai.packageName.equals("android")
                    || ai.packageName.startsWith("android.")
                    || ai.packageName.startsWith("com.android.")) {
                return true;
            }
        }
        return false;
    }

    
Initialize default ThreadPolicy for the current thread. 
@hide
/**
     * Initialize default {@link ThreadPolicy} for the current thread.
     *
     * @hide
     */
    public static void initThreadDefaults(ApplicationInfo ai) {
        final ThreadPolicy.Builder builder = new ThreadPolicy.Builder();
        final int targetSdkVersion =
                (ai != null) ? ai.targetSdkVersion : Build.VERSION_CODES.CUR_DEVELOPMENT;

        // Starting in HC, we don't allow network usage on the main thread
        if (targetSdkVersion >= Build.VERSION_CODES.HONEYCOMB) {
            builder.detectNetwork();
            builder.penaltyDeathOnNetwork();
        }

        if (Build.IS_USER || DISABLE || SystemProperties.getBoolean(DISABLE_PROPERTY, false)) {
            // Detect nothing extra
        } else if (Build.IS_USERDEBUG) {
            // Detect everything in bundled apps
            if (isBundledSystemApp(ai)) {
                builder.detectAll();
                builder.penaltyDropBox();
                if (SystemProperties.getBoolean(VISUAL_PROPERTY, false)) {
                    builder.penaltyFlashScreen();
                }
            }
        } else if (Build.IS_ENG) {
            // Detect everything in bundled apps
            if (isBundledSystemApp(ai)) {
                builder.detectAll();
                builder.penaltyDropBox();
                builder.penaltyLog();
                builder.penaltyFlashScreen();
            }
        }

        setThreadPolicy(builder.build());
    }

    
Initialize default VmPolicy for the current VM. 
@hide
/**
     * Initialize default {@link VmPolicy} for the current VM.
     *
     * @hide
     */
    public static void initVmDefaults(ApplicationInfo ai) {
        final VmPolicy.Builder builder = new VmPolicy.Builder();
        final int targetSdkVersion =
                (ai != null) ? ai.targetSdkVersion : Build.VERSION_CODES.CUR_DEVELOPMENT;

        // Starting in N, we don't allow file:// Uri exposure
        if (targetSdkVersion >= Build.VERSION_CODES.N) {
            builder.detectFileUriExposure();
            builder.penaltyDeathOnFileUriExposure();
        }

        if (Build.IS_USER || DISABLE || SystemProperties.getBoolean(DISABLE_PROPERTY, false)) {
            // Detect nothing extra
        } else if (Build.IS_USERDEBUG) {
            // Detect everything in bundled apps (except activity leaks, which
            // are expensive to track)
            if (isBundledSystemApp(ai)) {
                builder.detectAll();
                builder.permitActivityLeaks();
                builder.penaltyDropBox();
            }
        } else if (Build.IS_ENG) {
            // Detect everything in bundled apps
            if (isBundledSystemApp(ai)) {
                builder.detectAll();
                builder.penaltyDropBox();
                builder.penaltyLog();
            }
        }

        setVmPolicy(builder.build());
    }

    
Used by the framework to make file usage a fatal error.
@hide
/**
     * Used by the framework to make file usage a fatal error.
     *
     * @hide
     */
    public static void enableDeathOnFileUriExposure() {
        sVmPolicy =
                new VmPolicy(
                        sVmPolicy.mask
                                | DETECT_VM_FILE_URI_EXPOSURE
                                | PENALTY_DEATH_ON_FILE_URI_EXPOSURE,
                        sVmPolicy.classInstanceLimit,
                        sVmPolicy.mListener,
                        sVmPolicy.mCallbackExecutor);
    }

    
Used by lame internal apps that haven't done the hard work to get themselves off file:// Uris
yet.
@hide
/**
     * Used by lame internal apps that haven't done the hard work to get themselves off file:// Uris
     * yet.
     *
     * @hide
     */
    public static void disableDeathOnFileUriExposure() {
        sVmPolicy =
                new VmPolicy(
                        sVmPolicy.mask
                                & ~(DETECT_VM_FILE_URI_EXPOSURE
                                        | PENALTY_DEATH_ON_FILE_URI_EXPOSURE),
                        sVmPolicy.classInstanceLimit,
                        sVmPolicy.mListener,
                        sVmPolicy.mCallbackExecutor);
    }

    
Parses the BlockGuard policy mask out from the Exception's getMessage() String value. Kinda
gross, but least invasive. :/
Input is of the following forms: "policy=137 violation=64" "policy=137 violation=64
msg=Arbitrary text"
Returns 0 on failure, which is a valid policy, but not a valid policy during a violation
(else there must've been some policy in effect to violate).
/**
     * Parses the BlockGuard policy mask out from the Exception's getMessage() String value. Kinda
     * gross, but least invasive. :/
     *
     * <p>Input is of the following forms: "policy=137 violation=64" "policy=137 violation=64
     * msg=Arbitrary text"
     *
     * <p>Returns 0 on failure, which is a valid policy, but not a valid policy during a violation
     * (else there must've been some policy in effect to violate).
     */
    private static int parsePolicyFromMessage(String message) {
        if (message == null || !message.startsWith("policy=")) {
            return 0;
        }
        int spaceIndex = message.indexOf(' ');
        if (spaceIndex == -1) {
            return 0;
        }
        String policyString = message.substring(7, spaceIndex);
        try {
            return Integer.parseInt(policyString);
        } catch (NumberFormatException e) {
            return 0;
        }
    }

    private static final ThreadLocal<ArrayList<ViolationInfo>> violationsBeingTimed =
            new ThreadLocal<ArrayList<ViolationInfo>>() {
                @Override
                protected ArrayList<ViolationInfo> initialValue() {
                    return new ArrayList<ViolationInfo>();
                }
            };

    // Note: only access this once verifying the thread has a Looper.
    private static final ThreadLocal<Handler> THREAD_HANDLER =
            new ThreadLocal<Handler>() {
                @Override
                protected Handler initialValue() {
                    return new Handler();
                }
            };

    private static final ThreadLocal<AndroidBlockGuardPolicy> THREAD_ANDROID_POLICY =
            new ThreadLocal<AndroidBlockGuardPolicy>() {
                @Override
                protected AndroidBlockGuardPolicy initialValue() {
                    return new AndroidBlockGuardPolicy(0);
                }
            };

    private static boolean tooManyViolationsThisLoop() {
        return violationsBeingTimed.get().size() >= MAX_OFFENSES_PER_LOOP;
    }

    private static class AndroidBlockGuardPolicy implements BlockGuard.Policy {
        private int mPolicyMask;

        // Map from violation stacktrace hashcode -> uptimeMillis of
        // last violation.  No locking needed, as this is only
        // accessed by the same thread.
        private ArrayMap<Integer, Long> mLastViolationTime;

        public AndroidBlockGuardPolicy(final int policyMask) {
            mPolicyMask = policyMask;
        }

        @Override
        public String toString() {
            return "AndroidBlockGuardPolicy; mPolicyMask=" + mPolicyMask;
        }

        // Part of BlockGuard.Policy interface:
        public int getPolicyMask() {
            return mPolicyMask;
        }

        // Part of BlockGuard.Policy interface:
        public void onWriteToDisk() {
            if ((mPolicyMask & DETECT_DISK_WRITE) == 0) {
                return;
            }
            if (tooManyViolationsThisLoop()) {
                return;
            }
            startHandlingViolationException(new DiskWriteViolation());
        }

        // Not part of BlockGuard.Policy; just part of StrictMode:
        void onCustomSlowCall(String name) {
            if ((mPolicyMask & DETECT_CUSTOM) == 0) {
                return;
            }
            if (tooManyViolationsThisLoop()) {
                return;
            }
            startHandlingViolationException(new CustomViolation(name));
        }

        // Not part of BlockGuard.Policy; just part of StrictMode:
        void onResourceMismatch(Object tag) {
            if ((mPolicyMask & DETECT_RESOURCE_MISMATCH) == 0) {
                return;
            }
            if (tooManyViolationsThisLoop()) {
                return;
            }
            startHandlingViolationException(new ResourceMismatchViolation(tag));
        }

        // Not part of BlockGuard.Policy; just part of StrictMode:
        public void onUnbufferedIO() {
            if ((mPolicyMask & DETECT_UNBUFFERED_IO) == 0) {
                return;
            }
            if (tooManyViolationsThisLoop()) {
                return;
            }
            startHandlingViolationException(new UnbufferedIoViolation());
        }

        // Part of BlockGuard.Policy interface:
        public void onReadFromDisk() {
            if ((mPolicyMask & DETECT_DISK_READ) == 0) {
                return;
            }
            if (tooManyViolationsThisLoop()) {
                return;
            }
            startHandlingViolationException(new DiskReadViolation());
        }

        // Part of BlockGuard.Policy interface:
        public void onNetwork() {
            if ((mPolicyMask & DETECT_NETWORK) == 0) {
                return;
            }
            if ((mPolicyMask & PENALTY_DEATH_ON_NETWORK) != 0) {
                throw new NetworkOnMainThreadException();
            }
            if (tooManyViolationsThisLoop()) {
                return;
            }
            startHandlingViolationException(new NetworkViolation());
        }

        public void setPolicyMask(int policyMask) {
            mPolicyMask = policyMask;
        }

        // Start handling a violation that just started and hasn't
        // actually run yet (e.g. no disk write or network operation
        // has yet occurred).  This sees if we're in an event loop
        // thread and, if so, uses it to roughly measure how long the
        // violation took.
        void startHandlingViolationException(Violation e) {
            final ViolationInfo info = new ViolationInfo(e, mPolicyMask);
            info.violationUptimeMillis = SystemClock.uptimeMillis();
            handleViolationWithTimingAttempt(info);
        }

        // Attempts to fill in the provided ViolationInfo's
        // durationMillis field if this thread has a Looper we can use
        // to measure with.  We measure from the time of violation
        // until the time the looper is idle again (right before
        // the next epoll_wait)
        void handleViolationWithTimingAttempt(final ViolationInfo info) {
            Looper looper = Looper.myLooper();

            // Without a Looper, we're unable to time how long the
            // violation takes place.  This case should be rare, as
            // most users will care about timing violations that
            // happen on their main UI thread.  Note that this case is
            // also hit when a violation takes place in a Binder
            // thread, in "gather" mode.  In this case, the duration
            // of the violation is computed by the ultimate caller and
            // its Looper, if any.
            //
            // Also, as a special short-cut case when the only penalty
            // bit is death, we die immediately, rather than timing
            // the violation's duration.  This makes it convenient to
            // use in unit tests too, rather than waiting on a Looper.
            //
            // TODO: if in gather mode, ignore Looper.myLooper() and always
            //       go into this immediate mode?
            if (looper == null || (info.mPolicy & THREAD_PENALTY_MASK) == PENALTY_DEATH) {
                info.durationMillis = -1; // unknown (redundant, already set)
                onThreadPolicyViolation(info);
                return;
            }

            final ArrayList<ViolationInfo> records = violationsBeingTimed.get();
            if (records.size() >= MAX_OFFENSES_PER_LOOP) {
                // Not worth measuring.  Too many offenses in one loop.
                return;
            }
            records.add(info);
            if (records.size() > 1) {
                // There's already been a violation this loop, so we've already
                // registered an idle handler to process the list of violations
                // at the end of this Looper's loop.
                return;
            }

            final IWindowManager windowManager =
                    info.penaltyEnabled(PENALTY_FLASH) ? sWindowManager.get() : null;
            if (windowManager != null) {
                try {
                    windowManager.showStrictModeViolation(true);
                } catch (RemoteException unused) {
                }
            }

            // We post a runnable to a Handler (== delay 0 ms) for
            // measuring the end time of a violation instead of using
            // an IdleHandler (as was previously used) because an
            // IdleHandler may not run for quite a long period of time
            // if an ongoing animation is happening and continually
            // posting ASAP (0 ms) animation steps.  Animations are
            // throttled back to 60fps via SurfaceFlinger/View
            // invalidates, _not_ by posting frame updates every 16
            // milliseconds.
            THREAD_HANDLER
                    .get()
                    .postAtFrontOfQueue(
                            () -> {
                                long loopFinishTime = SystemClock.uptimeMillis();

                                // Note: we do this early, before handling the
                                // violation below, as handling the violation
                                // may include PENALTY_DEATH and we don't want
                                // to keep the red border on.
                                if (windowManager != null) {
                                    try {
                                        windowManager.showStrictModeViolation(false);
                                    } catch (RemoteException unused) {
                                    }
                                }

                                for (int n = 0; n < records.size(); ++n) {
                                    ViolationInfo v = records.get(n);
                                    v.violationNumThisLoop = n + 1;
                                    v.durationMillis =
                                            (int) (loopFinishTime - v.violationUptimeMillis);
                                    onThreadPolicyViolation(v);
                                }
                                records.clear();
                            });
        }

        // Note: It's possible (even quite likely) that the
        // thread-local policy mask has changed from the time the
        // violation fired and now (after the violating code ran) due
        // to people who push/pop temporary policy in regions of code,
        // hence the policy being passed around.
        void onThreadPolicyViolation(final ViolationInfo info) {
            if (LOG_V) Log.d(TAG, "onThreadPolicyViolation; policy=" + info.mPolicy);

            if (info.penaltyEnabled(PENALTY_GATHER)) {
                ArrayList<ViolationInfo> violations = gatheredViolations.get();
                if (violations == null) {
                    violations = new ArrayList<>(1);
                    gatheredViolations.set(violations);
                }
                for (ViolationInfo previous : violations) {
                    if (info.getStackTrace().equals(previous.getStackTrace())) {
                        // Duplicate. Don't log.
                        return;
                    }
                }
                violations.add(info);
                return;
            }

            // Not perfect, but fast and good enough for dup suppression.
            Integer crashFingerprint = info.hashCode();
            long lastViolationTime = 0;
            if (mLastViolationTime != null) {
                Long vtime = mLastViolationTime.get(crashFingerprint);
                if (vtime != null) {
                    lastViolationTime = vtime;
                }
            } else {
                mLastViolationTime = new ArrayMap<>(1);
            }
            long now = SystemClock.uptimeMillis();
            mLastViolationTime.put(crashFingerprint, now);
            long timeSinceLastViolationMillis =
                    lastViolationTime == 0 ? Long.MAX_VALUE : (now - lastViolationTime);

            if (info.penaltyEnabled(PENALTY_LOG)
                    && timeSinceLastViolationMillis > MIN_LOG_INTERVAL_MS) {
                sLogger.log(info);
            }

            final Violation violation = info.mViolation;

            // The violationMaskSubset, passed to ActivityManager, is a
            // subset of the original StrictMode policy bitmask, with
            // only the bit violated and penalty bits to be executed
            // by the ActivityManagerService remaining set.
            int violationMaskSubset = 0;

            if (info.penaltyEnabled(PENALTY_DIALOG)
                    && timeSinceLastViolationMillis > MIN_DIALOG_INTERVAL_MS) {
                violationMaskSubset |= PENALTY_DIALOG;
            }

            if (info.penaltyEnabled(PENALTY_DROPBOX) && lastViolationTime == 0) {
                violationMaskSubset |= PENALTY_DROPBOX;
            }

            if (violationMaskSubset != 0) {
                violationMaskSubset |= info.getViolationBit();

                final boolean justDropBox = (info.mPolicy & THREAD_PENALTY_MASK) == PENALTY_DROPBOX;
                if (justDropBox) {
                    // If all we're going to ask the activity manager
                    // to do is dropbox it (the common case during
                    // platform development), we can avoid doing this
                    // call synchronously which Binder data suggests
                    // isn't always super fast, despite the implementation
                    // in the ActivityManager trying to be mostly async.
                    dropboxViolationAsync(violationMaskSubset, info);
                } else {
                    handleApplicationStrictModeViolation(violationMaskSubset, info);
                }
            }

            if ((info.getPolicyMask() & PENALTY_DEATH) != 0) {
                throw new RuntimeException("StrictMode ThreadPolicy violation", violation);
            }

            // penaltyDeath will cause penaltyCallback to no-op since we cannot guarantee the
            // executor finishes before crashing.
            final OnThreadViolationListener listener = sThreadViolationListener.get();
            final Executor executor = sThreadViolationExecutor.get();
            if (listener != null && executor != null) {
                try {
                    executor.execute(
                            () -> {
                                // Lift violated policy to prevent infinite recursion.
                                ThreadPolicy oldPolicy = allowThreadViolations();
                                try {
                                    listener.onThreadViolation(violation);
                                } finally {
                                    setThreadPolicy(oldPolicy);
                                }
                            });
                } catch (RejectedExecutionException e) {
                    Log.e(TAG, "ThreadPolicy penaltyCallback failed", e);
                }
            }
        }
    }

    
In the common case, as set by conditionallyEnableDebugLogging, we're just dropboxing any
violations but not showing a dialog, not loggging, and not killing the process. In these
cases we don't need to do a synchronous call to the ActivityManager. This is used by both
per-thread and vm-wide violations when applicable.
/**
     * In the common case, as set by conditionallyEnableDebugLogging, we're just dropboxing any
     * violations but not showing a dialog, not loggging, and not killing the process. In these
     * cases we don't need to do a synchronous call to the ActivityManager. This is used by both
     * per-thread and vm-wide violations when applicable.
     */
    private static void dropboxViolationAsync(
            final int violationMaskSubset, final ViolationInfo info) {
        int outstanding = sDropboxCallsInFlight.incrementAndGet();
        if (outstanding > 20) {
            // What's going on?  Let's not make make the situation
            // worse and just not log.
            sDropboxCallsInFlight.decrementAndGet();
            return;
        }

        if (LOG_V) Log.d(TAG, "Dropboxing async; in-flight=" + outstanding);

        BackgroundThread.getHandler().post(() -> {
            handleApplicationStrictModeViolation(violationMaskSubset, info);
            int outstandingInner = sDropboxCallsInFlight.decrementAndGet();
            if (LOG_V) Log.d(TAG, "Dropbox complete; in-flight=" + outstandingInner);
        });
    }

    private static void handleApplicationStrictModeViolation(int violationMaskSubset,
            ViolationInfo info) {
        final int oldMask = getThreadPolicyMask();
        try {
            // First, remove any policy before we call into the Activity Manager,
            // otherwise we'll infinite recurse as we try to log policy violations
            // to disk, thus violating policy, thus requiring logging, etc...
            // We restore the current policy below, in the finally block.
            setThreadPolicyMask(0);

            IActivityManager am = ActivityManager.getService();
            if (am == null) {
                Log.w(TAG, "No activity manager; failed to Dropbox violation.");
            } else {
                am.handleApplicationStrictModeViolation(
                        RuntimeInit.getApplicationObject(), violationMaskSubset, info);
            }
        } catch (RemoteException e) {
            if (e instanceof DeadObjectException) {
                // System process is dead; ignore
            } else {
                Log.e(TAG, "RemoteException handling StrictMode violation", e);
            }
        } finally {
            setThreadPolicyMask(oldMask);
        }
    }

    private static class AndroidCloseGuardReporter implements CloseGuard.Reporter {
        public void report(String message, Throwable allocationSite) {
            onVmPolicyViolation(new LeakedClosableViolation(message, allocationSite));
        }
    }

    
Called from Parcel.writeNoException() /** Called from Parcel.writeNoException() */
    /* package */ static boolean hasGatheredViolations() {
        return gatheredViolations.get() != null;
    }

    
Called from Parcel.writeException(), so we drop this memory and don't incorrectly attribute
it to the wrong caller on the next Binder call on this thread.
/**
     * Called from Parcel.writeException(), so we drop this memory and don't incorrectly attribute
     * it to the wrong caller on the next Binder call on this thread.
     */
    /* package */ static void clearGatheredViolations() {
        gatheredViolations.set(null);
    }

    
@hide
/** @hide */
    public static void conditionallyCheckInstanceCounts() {
        VmPolicy policy = getVmPolicy();
        int policySize = policy.classInstanceLimit.size();
        if (policySize == 0) {
            return;
        }

        System.gc();
        System.runFinalization();
        System.gc();

        // Note: classInstanceLimit is immutable, so this is lock-free
        // Create the classes array.
        Class[] classes = policy.classInstanceLimit.keySet().toArray(new Class[policySize]);
        long[] instanceCounts = VMDebug.countInstancesOfClasses(classes, false);
        for (int i = 0; i < classes.length; ++i) {
            Class klass = classes[i];
            int limit = policy.classInstanceLimit.get(klass);
            long instances = instanceCounts[i];
            if (instances > limit) {
                onVmPolicyViolation(new InstanceCountViolation(klass, instances, limit));
            }
        }
    }

    private static long sLastInstanceCountCheckMillis = 0;
    private static boolean sIsIdlerRegistered = false; // guarded by StrictMode.class
    private static final MessageQueue.IdleHandler sProcessIdleHandler =
            new MessageQueue.IdleHandler() {
                public boolean queueIdle() {
                    long now = SystemClock.uptimeMillis();
                    if (now - sLastInstanceCountCheckMillis > 30 * 1000) {
                        sLastInstanceCountCheckMillis = now;
                        conditionallyCheckInstanceCounts();
                    }
                    return true;
                }
            };

    
Sets the policy for what actions in the VM process (on any thread) should be detected, as
well as the penalty if such actions occur.
Params:
policy – the policy to put into place/**
     * Sets the policy for what actions in the VM process (on any thread) should be detected, as
     * well as the penalty if such actions occur.
     *
     * @param policy the policy to put into place
     */
    public static void setVmPolicy(final VmPolicy policy) {
        synchronized (StrictMode.class) {
            sVmPolicy = policy;
            setCloseGuardEnabled(vmClosableObjectLeaksEnabled());

            Looper looper = Looper.getMainLooper();
            if (looper != null) {
                MessageQueue mq = looper.mQueue;
                if (policy.classInstanceLimit.size() == 0
                        || (sVmPolicy.mask & VM_PENALTY_MASK) == 0) {
                    mq.removeIdleHandler(sProcessIdleHandler);
                    sIsIdlerRegistered = false;
                } else if (!sIsIdlerRegistered) {
                    mq.addIdleHandler(sProcessIdleHandler);
                    sIsIdlerRegistered = true;
                }
            }

            int networkPolicy = NETWORK_POLICY_ACCEPT;
            if ((sVmPolicy.mask & DETECT_VM_CLEARTEXT_NETWORK) != 0) {
                if ((sVmPolicy.mask & PENALTY_DEATH) != 0
                        || (sVmPolicy.mask & PENALTY_DEATH_ON_CLEARTEXT_NETWORK) != 0) {
                    networkPolicy = NETWORK_POLICY_REJECT;
                } else {
                    networkPolicy = NETWORK_POLICY_LOG;
                }
            }

            final INetworkManagementService netd =
                    INetworkManagementService.Stub.asInterface(
                            ServiceManager.getService(Context.NETWORKMANAGEMENT_SERVICE));
            if (netd != null) {
                try {
                    netd.setUidCleartextNetworkPolicy(android.os.Process.myUid(), networkPolicy);
                } catch (RemoteException ignored) {
                }
            } else if (networkPolicy != NETWORK_POLICY_ACCEPT) {
                Log.w(TAG, "Dropping requested network policy due to missing service!");
            }


            if ((sVmPolicy.mask & DETECT_VM_NON_SDK_API_USAGE) != 0) {
                VMRuntime.setNonSdkApiUsageConsumer(sNonSdkApiUsageConsumer);
                VMRuntime.setDedupeHiddenApiWarnings(false);
            } else {
                VMRuntime.setNonSdkApiUsageConsumer(null);
                VMRuntime.setDedupeHiddenApiWarnings(true);
            }
        }
    }

    
Gets the current VM policy. /** Gets the current VM policy. */
    public static VmPolicy getVmPolicy() {
        synchronized (StrictMode.class) {
            return sVmPolicy;
        }
    }

    
Enable the recommended StrictMode defaults, with violations just being logged.
This catches disk and network access on the main thread, as well as leaked SQLite cursors and unclosed resources. This is simply a wrapper around setVmPolicy and setThreadPolicy. /**
     * Enable the recommended StrictMode defaults, with violations just being logged.
     *
     * <p>This catches disk and network access on the main thread, as well as leaked SQLite cursors
     * and unclosed resources. This is simply a wrapper around {@link #setVmPolicy} and {@link
     * #setThreadPolicy}.
     */
    public static void enableDefaults() {
        setThreadPolicy(new StrictMode.ThreadPolicy.Builder().detectAll().penaltyLog().build());
        setVmPolicy(new StrictMode.VmPolicy.Builder().detectAll().penaltyLog().build());
    }

    
@hide
/** @hide */
    public static boolean vmSqliteObjectLeaksEnabled() {
        return (sVmPolicy.mask & DETECT_VM_CURSOR_LEAKS) != 0;
    }

    
@hide
/** @hide */
    public static boolean vmClosableObjectLeaksEnabled() {
        return (sVmPolicy.mask & DETECT_VM_CLOSABLE_LEAKS) != 0;
    }

    
@hide
/** @hide */
    public static boolean vmRegistrationLeaksEnabled() {
        return (sVmPolicy.mask & DETECT_VM_REGISTRATION_LEAKS) != 0;
    }

    
@hide
/** @hide */
    public static boolean vmFileUriExposureEnabled() {
        return (sVmPolicy.mask & DETECT_VM_FILE_URI_EXPOSURE) != 0;
    }

    
@hide
/** @hide */
    public static boolean vmCleartextNetworkEnabled() {
        return (sVmPolicy.mask & DETECT_VM_CLEARTEXT_NETWORK) != 0;
    }

    
@hide
/** @hide */
    public static boolean vmContentUriWithoutPermissionEnabled() {
        return (sVmPolicy.mask & DETECT_VM_CONTENT_URI_WITHOUT_PERMISSION) != 0;
    }

    
@hide
/** @hide */
    public static boolean vmUntaggedSocketEnabled() {
        return (sVmPolicy.mask & DETECT_VM_UNTAGGED_SOCKET) != 0;
    }

    
@hide
/** @hide */
    public static void onSqliteObjectLeaked(String message, Throwable originStack) {
        onVmPolicyViolation(new SqliteObjectLeakedViolation(message, originStack));
    }

    
@hide
/** @hide */
    public static void onWebViewMethodCalledOnWrongThread(Throwable originStack) {
        onVmPolicyViolation(new WebViewMethodCalledOnWrongThreadViolation(originStack));
    }

    
@hide
/** @hide */
    public static void onIntentReceiverLeaked(Throwable originStack) {
        onVmPolicyViolation(new IntentReceiverLeakedViolation(originStack));
    }

    
@hide
/** @hide */
    public static void onServiceConnectionLeaked(Throwable originStack) {
        onVmPolicyViolation(new ServiceConnectionLeakedViolation(originStack));
    }

    
@hide
/** @hide */
    public static void onFileUriExposed(Uri uri, String location) {
        final String message = uri + " exposed beyond app through " + location;
        if ((sVmPolicy.mask & PENALTY_DEATH_ON_FILE_URI_EXPOSURE) != 0) {
            throw new FileUriExposedException(message);
        } else {
            onVmPolicyViolation(new FileUriExposedViolation(message));
        }
    }

    
@hide
/** @hide */
    public static void onContentUriWithoutPermission(Uri uri, String location) {
        onVmPolicyViolation(new ContentUriWithoutPermissionViolation(uri, location));
    }

    
@hide
/** @hide */
    public static final String CLEARTEXT_DETECTED_MSG =
            "Detected cleartext network traffic from UID ";

    
@hide
/** @hide */
    public static void onCleartextNetworkDetected(byte[] firstPacket) {
        byte[] rawAddr = null;
        if (firstPacket != null) {
            if (firstPacket.length >= 20 && (firstPacket[0] & 0xf0) == 0x40) {
                // IPv4
                rawAddr = new byte[4];
                System.arraycopy(firstPacket, 16, rawAddr, 0, 4);
            } else if (firstPacket.length >= 40 && (firstPacket[0] & 0xf0) == 0x60) {
                // IPv6
                rawAddr = new byte[16];
                System.arraycopy(firstPacket, 24, rawAddr, 0, 16);
            }
        }

        final int uid = android.os.Process.myUid();
        String msg = CLEARTEXT_DETECTED_MSG + uid;
        if (rawAddr != null) {
            try {
                msg += " to " + InetAddress.getByAddress(rawAddr);
            } catch (UnknownHostException ignored) {
            }
        }
        msg += HexDump.dumpHexString(firstPacket).trim() + " ";
        final boolean forceDeath = (sVmPolicy.mask & PENALTY_DEATH_ON_CLEARTEXT_NETWORK) != 0;
        onVmPolicyViolation(new CleartextNetworkViolation(msg), forceDeath);
    }

    
@hide
/** @hide */
    public static void onUntaggedSocket() {
        onVmPolicyViolation(new UntaggedSocketViolation());
    }

    // Map from VM violation fingerprint to uptime millis.
    private static final HashMap<Integer, Long> sLastVmViolationTime = new HashMap<>();

    
@hide
/** @hide */
    public static void onVmPolicyViolation(Violation originStack) {
        onVmPolicyViolation(originStack, false);
    }

    
@hide
/** @hide */
    public static void onVmPolicyViolation(Violation violation, boolean forceDeath) {
        final boolean penaltyDropbox = (sVmPolicy.mask & PENALTY_DROPBOX) != 0;
        final boolean penaltyDeath = ((sVmPolicy.mask & PENALTY_DEATH) != 0) || forceDeath;
        final boolean penaltyLog = (sVmPolicy.mask & PENALTY_LOG) != 0;
        final ViolationInfo info = new ViolationInfo(violation, sVmPolicy.mask);

        // Erase stuff not relevant for process-wide violations
        info.numAnimationsRunning = 0;
        info.tags = null;
        info.broadcastIntentAction = null;

        final Integer fingerprint = info.hashCode();
        final long now = SystemClock.uptimeMillis();
        long lastViolationTime;
        long timeSinceLastViolationMillis = Long.MAX_VALUE;
        synchronized (sLastVmViolationTime) {
            if (sLastVmViolationTime.containsKey(fingerprint)) {
                lastViolationTime = sLastVmViolationTime.get(fingerprint);
                timeSinceLastViolationMillis = now - lastViolationTime;
            }
            if (timeSinceLastViolationMillis > MIN_VM_INTERVAL_MS) {
                sLastVmViolationTime.put(fingerprint, now);
            }
        }
        if (timeSinceLastViolationMillis <= MIN_VM_INTERVAL_MS) {
            // Rate limit all penalties.
            return;
        }

        if (penaltyLog && sLogger != null && timeSinceLastViolationMillis > MIN_LOG_INTERVAL_MS) {
            sLogger.log(info);
        }

        int violationMaskSubset = PENALTY_DROPBOX | (ALL_VM_DETECT_BITS & sVmPolicy.mask);

        if (penaltyDropbox) {
            if (penaltyDeath) {
                handleApplicationStrictModeViolation(violationMaskSubset, info);
            } else {
                // Common case for userdebug/eng builds.  If no death and
                // just dropboxing, we can do the ActivityManager call
                // asynchronously.
                dropboxViolationAsync(violationMaskSubset, info);
            }
        }

        if (penaltyDeath) {
            System.err.println("StrictMode VmPolicy violation with POLICY_DEATH; shutting down.");
            Process.killProcess(Process.myPid());
            System.exit(10);
        }

        // If penaltyDeath, we can't guarantee this callback finishes before the process dies for
        // all executors. penaltyDeath supersedes penaltyCallback.
        if (sVmPolicy.mListener != null && sVmPolicy.mCallbackExecutor != null) {
            final OnVmViolationListener listener = sVmPolicy.mListener;
            try {
                sVmPolicy.mCallbackExecutor.execute(
                        () -> {
                            // Lift violated policy to prevent infinite recursion.
                            VmPolicy oldPolicy = allowVmViolations();
                            try {
                                listener.onVmViolation(violation);
                            } finally {
                                setVmPolicy(oldPolicy);
                            }
                        });
            } catch (RejectedExecutionException e) {
                Log.e(TAG, "VmPolicy penaltyCallback failed", e);
            }
        }
    }

    
Called from Parcel.writeNoException() /** Called from Parcel.writeNoException() */
    /* package */ static void writeGatheredViolationsToParcel(Parcel p) {
        ArrayList<ViolationInfo> violations = gatheredViolations.get();
        if (violations == null) {
            p.writeInt(0);
        } else {
            // To avoid taking up too much transaction space, only include
            // details for the first 3 violations. Deep inside, CrashInfo
            // will truncate each stack trace to ~20kB.
            final int size = Math.min(violations.size(), 3);
            p.writeInt(size);
            for (int i = 0; i < size; i++) {
                violations.get(i).writeToParcel(p, 0);
            }
        }
        gatheredViolations.set(null);
    }

    
Called from Parcel.readException() when the exception is EX_STRICT_MODE_VIOLATIONS, we here
read back all the encoded violations.
/**
     * Called from Parcel.readException() when the exception is EX_STRICT_MODE_VIOLATIONS, we here
     * read back all the encoded violations.
     */
    /* package */ static void readAndHandleBinderCallViolations(Parcel p) {
        Throwable localCallSite = new Throwable();
        final int policyMask = getThreadPolicyMask();
        final boolean currentlyGathering = (policyMask & PENALTY_GATHER) != 0;

        final int size = p.readInt();
        for (int i = 0; i < size; i++) {
            final ViolationInfo info = new ViolationInfo(p, !currentlyGathering);
            info.addLocalStack(localCallSite);
            BlockGuard.Policy policy = BlockGuard.getThreadPolicy();
            if (policy instanceof AndroidBlockGuardPolicy) {
                ((AndroidBlockGuardPolicy) policy).handleViolationWithTimingAttempt(info);
            }
        }
    }

    
Called from android_util_Binder.cpp's android_os_Parcel_enforceInterface when an incoming
Binder call requires changing the StrictMode policy mask. The role of this function is to ask
Binder for its current (native) thread-local policy value and synchronize it to libcore's
(Java) thread-local policy value.
/**
     * Called from android_util_Binder.cpp's android_os_Parcel_enforceInterface when an incoming
     * Binder call requires changing the StrictMode policy mask. The role of this function is to ask
     * Binder for its current (native) thread-local policy value and synchronize it to libcore's
     * (Java) thread-local policy value.
     */
    private static void onBinderStrictModePolicyChange(int newPolicy) {
        setBlockGuardPolicy(newPolicy);
    }

    
A tracked, critical time span. (e.g. during an animation.)
The object itself is a linked list node, to avoid any allocations during rapid span
entries and exits.
@hide
/**
     * A tracked, critical time span. (e.g. during an animation.)
     *
     * <p>The object itself is a linked list node, to avoid any allocations during rapid span
     * entries and exits.
     *
     * @hide
     */
    public static class Span {
        private String mName;
        private long mCreateMillis;
        private Span mNext;
        private Span mPrev; // not used when in freeList, only active
        private final ThreadSpanState mContainerState;

        Span(ThreadSpanState threadState) {
            mContainerState = threadState;
        }

        // Empty constructor for the NO_OP_SPAN
        protected Span() {
            mContainerState = null;
        }

        
To be called when the critical span is complete (i.e. the animation is done animating).
This can be called on any thread (even a different one from where the animation was
taking place), but that's only a defensive implementation measure. It really makes no
sense for you to call this on thread other than that where you created it.
@hide
/**
         * To be called when the critical span is complete (i.e. the animation is done animating).
         * This can be called on any thread (even a different one from where the animation was
         * taking place), but that's only a defensive implementation measure. It really makes no
         * sense for you to call this on thread other than that where you created it.
         *
         * @hide
         */
        public void finish() {
            ThreadSpanState state = mContainerState;
            synchronized (state) {
                if (mName == null) {
                    // Duplicate finish call.  Ignore.
                    return;
                }

                // Remove ourselves from the active list.
                if (mPrev != null) {
                    mPrev.mNext = mNext;
                }
                if (mNext != null) {
                    mNext.mPrev = mPrev;
                }
                if (state.mActiveHead == this) {
                    state.mActiveHead = mNext;
                }

                state.mActiveSize--;

                if (LOG_V) Log.d(TAG, "Span finished=" + mName + "; size=" + state.mActiveSize);

                this.mCreateMillis = -1;
                this.mName = null;
                this.mPrev = null;
                this.mNext = null;

                // Add ourselves to the freeList, if it's not already
                // too big.
                if (state.mFreeListSize < 5) {
                    this.mNext = state.mFreeListHead;
                    state.mFreeListHead = this;
                    state.mFreeListSize++;
                }
            }
        }
    }

    // The no-op span that's used in user builds.
    private static final Span NO_OP_SPAN =
            new Span() {
                public void finish() {
                    // Do nothing.
                }
            };

    
Linked lists of active spans and a freelist.
Locking notes: there's one of these structures per thread and all members of this
structure (as well as the Span nodes under it) are guarded by the ThreadSpanState object
instance. While in theory there'd be no locking required because it's all local per-thread,
the finish() method above is defensive against people calling it on a different thread from
where they created the Span, hence the locking.
/**
     * Linked lists of active spans and a freelist.
     *
     * <p>Locking notes: there's one of these structures per thread and all members of this
     * structure (as well as the Span nodes under it) are guarded by the ThreadSpanState object
     * instance. While in theory there'd be no locking required because it's all local per-thread,
     * the finish() method above is defensive against people calling it on a different thread from
     * where they created the Span, hence the locking.
     */
    private static class ThreadSpanState {
        public Span mActiveHead; // doubly-linked list.
        public int mActiveSize;
        public Span mFreeListHead; // singly-linked list.  only changes at head.
        public int mFreeListSize;
    }

    private static final ThreadLocal<ThreadSpanState> sThisThreadSpanState =
            new ThreadLocal<ThreadSpanState>() {
                @Override
                protected ThreadSpanState initialValue() {
                    return new ThreadSpanState();
                }
            };

    private static Singleton<IWindowManager> sWindowManager =
            new Singleton<IWindowManager>() {
                protected IWindowManager create() {
                    return IWindowManager.Stub.asInterface(ServiceManager.getService("window"));
                }
            };

    
Enter a named critical span (e.g. an animation)
The name is an arbitary label (or tag) that will be applied to any strictmode violation
that happens while this span is active. You must call finish() on the span when done.
This will never return null, but on devices without debugging enabled, this may return a
dummy object on which the finish() method is a no-op.
TODO: add CloseGuard to this, verifying callers call finish.
@hide
/**
     * Enter a named critical span (e.g. an animation)
     *
     * <p>The name is an arbitary label (or tag) that will be applied to any strictmode violation
     * that happens while this span is active. You must call finish() on the span when done.
     *
     * <p>This will never return null, but on devices without debugging enabled, this may return a
     * dummy object on which the finish() method is a no-op.
     *
     * <p>TODO: add CloseGuard to this, verifying callers call finish.
     *
     * @hide
     */
    public static Span enterCriticalSpan(String name) {
        if (Build.IS_USER) {
            return NO_OP_SPAN;
        }
        if (name == null || name.isEmpty()) {
            throw new IllegalArgumentException("name must be non-null and non-empty");
        }
        ThreadSpanState state = sThisThreadSpanState.get();
        Span span = null;
        synchronized (state) {
            if (state.mFreeListHead != null) {
                span = state.mFreeListHead;
                state.mFreeListHead = span.mNext;
                state.mFreeListSize--;
            } else {
                // Shouldn't have to do this often.
                span = new Span(state);
            }
            span.mName = name;
            span.mCreateMillis = SystemClock.uptimeMillis();
            span.mNext = state.mActiveHead;
            span.mPrev = null;
            state.mActiveHead = span;
            state.mActiveSize++;
            if (span.mNext != null) {
                span.mNext.mPrev = span;
            }
            if (LOG_V) Log.d(TAG, "Span enter=" + name + "; size=" + state.mActiveSize);
        }
        return span;
    }

    
For code to note that it's slow. This is a no-op unless the current thread's ThreadPolicy has Builder.detectCustomSlowCalls enabled. 
Params:
name – a short string for the exception stack trace that's built if when this fires./**
     * For code to note that it's slow. This is a no-op unless the current thread's {@link
     * android.os.StrictMode.ThreadPolicy} has {@link
     * android.os.StrictMode.ThreadPolicy.Builder#detectCustomSlowCalls} enabled.
     *
     * @param name a short string for the exception stack trace that's built if when this fires.
     */
    public static void noteSlowCall(String name) {
        BlockGuard.Policy policy = BlockGuard.getThreadPolicy();
        if (!(policy instanceof AndroidBlockGuardPolicy)) {
            // StrictMode not enabled.
            return;
        }
        ((AndroidBlockGuardPolicy) policy).onCustomSlowCall(name);
    }

    
For code to note that a resource was obtained using a type other than its defined type. This is a no-op unless the current thread's ThreadPolicy has Builder.detectResourceMismatches() enabled. 
Params:
tag – an object for the exception stack trace that's built if when this fires.
@hide
/**
     * For code to note that a resource was obtained using a type other than its defined type. This
     * is a no-op unless the current thread's {@link android.os.StrictMode.ThreadPolicy} has {@link
     * android.os.StrictMode.ThreadPolicy.Builder#detectResourceMismatches()} enabled.
     *
     * @param tag an object for the exception stack trace that's built if when this fires.
     * @hide
     */
    public static void noteResourceMismatch(Object tag) {
        BlockGuard.Policy policy = BlockGuard.getThreadPolicy();
        if (!(policy instanceof AndroidBlockGuardPolicy)) {
            // StrictMode not enabled.
            return;
        }
        ((AndroidBlockGuardPolicy) policy).onResourceMismatch(tag);
    }

    
@hide
/** @hide */
    public static void noteUnbufferedIO() {
        BlockGuard.Policy policy = BlockGuard.getThreadPolicy();
        if (!(policy instanceof AndroidBlockGuardPolicy)) {
            // StrictMode not enabled.
            return;
        }
        policy.onUnbufferedIO();
    }

    
@hide
/** @hide */
    public static void noteDiskRead() {
        BlockGuard.Policy policy = BlockGuard.getThreadPolicy();
        if (!(policy instanceof AndroidBlockGuardPolicy)) {
            // StrictMode not enabled.
            return;
        }
        policy.onReadFromDisk();
    }

    
@hide
/** @hide */
    public static void noteDiskWrite() {
        BlockGuard.Policy policy = BlockGuard.getThreadPolicy();
        if (!(policy instanceof AndroidBlockGuardPolicy)) {
            // StrictMode not enabled.
            return;
        }
        policy.onWriteToDisk();
    }

    @GuardedBy("StrictMode.class")
    private static final HashMap<Class, Integer> sExpectedActivityInstanceCount = new HashMap<>();

    
Returns an object that is used to track instances of activites. The activity should store a
reference to the tracker object in one of its fields.
@hide
/**
     * Returns an object that is used to track instances of activites. The activity should store a
     * reference to the tracker object in one of its fields.
     *
     * @hide
     */
    public static Object trackActivity(Object instance) {
        return new InstanceTracker(instance);
    }

    
@hide
/** @hide */
    public static void incrementExpectedActivityCount(Class klass) {
        if (klass == null) {
            return;
        }

        synchronized (StrictMode.class) {
            if ((sVmPolicy.mask & DETECT_VM_ACTIVITY_LEAKS) == 0) {
                return;
            }

            Integer expected = sExpectedActivityInstanceCount.get(klass);
            Integer newExpected = expected == null ? 1 : expected + 1;
            sExpectedActivityInstanceCount.put(klass, newExpected);
        }
    }

    
@hide
/** @hide */
    public static void decrementExpectedActivityCount(Class klass) {
        if (klass == null) {
            return;
        }

        final int limit;
        synchronized (StrictMode.class) {
            if ((sVmPolicy.mask & DETECT_VM_ACTIVITY_LEAKS) == 0) {
                return;
            }

            Integer expected = sExpectedActivityInstanceCount.get(klass);
            int newExpected = (expected == null || expected == 0) ? 0 : expected - 1;
            if (newExpected == 0) {
                sExpectedActivityInstanceCount.remove(klass);
            } else {
                sExpectedActivityInstanceCount.put(klass, newExpected);
            }

            // Note: adding 1 here to give some breathing room during
            // orientation changes.  (shouldn't be necessary, though?)
            limit = newExpected + 1;
        }

        // Quick check.
        int actual = InstanceTracker.getInstanceCount(klass);
        if (actual <= limit) {
            return;
        }

        // Do a GC and explicit count to double-check.
        // This is the work that we are trying to avoid by tracking the object instances
        // explicity.  Running an explicit GC can be expensive (80ms) and so can walking
        // the heap to count instance (30ms).  This extra work can make the system feel
        // noticeably less responsive during orientation changes when activities are
        // being restarted.  Granted, it is only a problem when StrictMode is enabled
        // but it is annoying.

        System.gc();
        System.runFinalization();
        System.gc();

        long instances = VMDebug.countInstancesOfClass(klass, false);
        if (instances > limit) {
            onVmPolicyViolation(new InstanceCountViolation(klass, instances, limit));
        }
    }

    
Parcelable that gets sent in Binder call headers back to callers to report violations that
happened during a cross-process call.
@hide
/**
     * Parcelable that gets sent in Binder call headers back to callers to report violations that
     * happened during a cross-process call.
     *
     * @hide
     */
    @TestApi
    public static final class ViolationInfo implements Parcelable {
        
Stack and violation details. /** Stack and violation details. */
        private final Violation mViolation;

        
Path leading to a violation that occurred across binder. /** Path leading to a violation that occurred across binder. */
        private final Deque<StackTraceElement[]> mBinderStack = new ArrayDeque<>();

        
Memoized stack trace of full violation. /** Memoized stack trace of full violation. */
        @Nullable private String mStackTrace;

        
The strict mode policy mask at the time of violation. /** The strict mode policy mask at the time of violation. */
        private final int mPolicy;

        
The wall time duration of the violation, when known. -1 when not known. /** The wall time duration of the violation, when known. -1 when not known. */
        public int durationMillis = -1;

        
The number of animations currently running. /** The number of animations currently running. */
        public int numAnimationsRunning = 0;

        
List of tags from active Span instances during this violation, or null for none. /** List of tags from active Span instances during this violation, or null for none. */
        public String[] tags;

        
Which violation number this was (1-based) since the last Looper loop, from the
perspective of the root caller (if it crossed any processes via Binder calls). The value
is 0 if the root caller wasn't on a Looper thread.
/**
         * Which violation number this was (1-based) since the last Looper loop, from the
         * perspective of the root caller (if it crossed any processes via Binder calls). The value
         * is 0 if the root caller wasn't on a Looper thread.
         */
        public int violationNumThisLoop;

        
The time (in terms of SystemClock.uptimeMillis()) that the violation occurred. /** The time (in terms of SystemClock.uptimeMillis()) that the violation occurred. */
        public long violationUptimeMillis;

        
The action of the Intent being broadcast to somebody's onReceive on this thread right
now, or null.
/**
         * The action of the Intent being broadcast to somebody's onReceive on this thread right
         * now, or null.
         */
        public String broadcastIntentAction;

        
If this is a instance count violation, the number of instances in memory, else -1. /** If this is a instance count violation, the number of instances in memory, else -1. */
        public long numInstances = -1;

        
Create an instance of ViolationInfo initialized from an exception. /** Create an instance of ViolationInfo initialized from an exception. */
        ViolationInfo(Violation tr, int policy) {
            this.mViolation = tr;
            this.mPolicy = policy;
            violationUptimeMillis = SystemClock.uptimeMillis();
            this.numAnimationsRunning = ValueAnimator.getCurrentAnimationsCount();
            Intent broadcastIntent = ActivityThread.getIntentBeingBroadcast();
            if (broadcastIntent != null) {
                broadcastIntentAction = broadcastIntent.getAction();
            }
            ThreadSpanState state = sThisThreadSpanState.get();
            if (tr instanceof InstanceCountViolation) {
                this.numInstances = ((InstanceCountViolation) tr).getNumberOfInstances();
            }
            synchronized (state) {
                int spanActiveCount = state.mActiveSize;
                if (spanActiveCount > MAX_SPAN_TAGS) {
                    spanActiveCount = MAX_SPAN_TAGS;
                }
                if (spanActiveCount != 0) {
                    this.tags = new String[spanActiveCount];
                    Span iter = state.mActiveHead;
                    int index = 0;
                    while (iter != null && index < spanActiveCount) {
                        this.tags[index] = iter.mName;
                        index++;
                        iter = iter.mNext;
                    }
                }
            }
        }

        
Equivalent output to stackTrace.stackTrace. /** Equivalent output to {@link ApplicationErrorReport.CrashInfo#stackTrace}. */
        public String getStackTrace() {
            if (mStackTrace == null) {
                StringWriter sw = new StringWriter();
                PrintWriter pw = new FastPrintWriter(sw, false, 256);
                mViolation.printStackTrace(pw);
                for (StackTraceElement[] traces : mBinderStack) {
                    pw.append("# via Binder call with stack:\n");
                    for (StackTraceElement traceElement : traces) {
                        pw.append("\tat ");
                        pw.append(traceElement.toString());
                        pw.append('\n');
                    }
                }
                pw.flush();
                pw.close();
                mStackTrace = sw.toString();
            }
            return mStackTrace;
        }

        
Optional message describing this violation.
@hide
/**
         * Optional message describing this violation.
         *
         * @hide
         */
        @TestApi
        public String getViolationDetails() {
            return mViolation.getMessage();
        }

        
Policy mask at time of violation.
@hide
/**
         * Policy mask at time of violation.
         *
         * @hide
         */
        @TestApi
        public int getPolicyMask() {
            return mPolicy;
        }

        boolean penaltyEnabled(int p) {
            return (mPolicy & p) != 0;
        }

        
Add a Throwable from the current process that caused the underlying violation. We only preserve the stack trace elements. 
@hide
/**
         * Add a {@link Throwable} from the current process that caused the underlying violation. We
         * only preserve the stack trace elements.
         *
         * @hide
         */
        void addLocalStack(Throwable t) {
            mBinderStack.addFirst(t.getStackTrace());
        }

        
Retrieve the type of StrictMode violation.
@hide
/**
         * Retrieve the type of StrictMode violation.
         *
         * @hide
         */
        @TestApi
        public int getViolationBit() {
            if (mViolation instanceof DiskWriteViolation) {
                return DETECT_DISK_WRITE;
            } else if (mViolation instanceof DiskReadViolation) {
                return DETECT_DISK_READ;
            } else if (mViolation instanceof NetworkViolation) {
                return DETECT_NETWORK;
            } else if (mViolation instanceof CustomViolation) {
                return DETECT_CUSTOM;
            } else if (mViolation instanceof ResourceMismatchViolation) {
                return DETECT_RESOURCE_MISMATCH;
            } else if (mViolation instanceof UnbufferedIoViolation) {
                return DETECT_UNBUFFERED_IO;
            } else if (mViolation instanceof SqliteObjectLeakedViolation) {
                return DETECT_VM_CURSOR_LEAKS;
            } else if (mViolation instanceof LeakedClosableViolation) {
                return DETECT_VM_CLOSABLE_LEAKS;
            } else if (mViolation instanceof InstanceCountViolation) {
                return DETECT_VM_INSTANCE_LEAKS;
            } else if (mViolation instanceof IntentReceiverLeakedViolation) {
                return DETECT_VM_REGISTRATION_LEAKS;
            } else if (mViolation instanceof ServiceConnectionLeakedViolation) {
                return DETECT_VM_REGISTRATION_LEAKS;
            } else if (mViolation instanceof FileUriExposedViolation) {
                return DETECT_VM_FILE_URI_EXPOSURE;
            } else if (mViolation instanceof CleartextNetworkViolation) {
                return DETECT_VM_CLEARTEXT_NETWORK;
            } else if (mViolation instanceof ContentUriWithoutPermissionViolation) {
                return DETECT_VM_CONTENT_URI_WITHOUT_PERMISSION;
            } else if (mViolation instanceof UntaggedSocketViolation) {
                return DETECT_VM_UNTAGGED_SOCKET;
            } else if (mViolation instanceof NonSdkApiUsedViolation) {
                return DETECT_VM_NON_SDK_API_USAGE;
            }
            throw new IllegalStateException("missing violation bit");
        }

        @Override
        public int hashCode() {
            int result = 17;
            if (mViolation != null) {
                result = 37 * result + mViolation.hashCode();
            }
            if (numAnimationsRunning != 0) {
                result *= 37;
            }
            if (broadcastIntentAction != null) {
                result = 37 * result + broadcastIntentAction.hashCode();
            }
            if (tags != null) {
                for (String tag : tags) {
                    result = 37 * result + tag.hashCode();
                }
            }
            return result;
        }

        
Create an instance of ViolationInfo initialized from a Parcel. /** Create an instance of ViolationInfo initialized from a Parcel. */
        public ViolationInfo(Parcel in) {
            this(in, false);
        }

        
Create an instance of ViolationInfo initialized from a Parcel.
Params:
unsetGatheringBit – if true, the caller is the root caller and the gathering penalty
    should be removed./**
         * Create an instance of ViolationInfo initialized from a Parcel.
         *
         * @param unsetGatheringBit if true, the caller is the root caller and the gathering penalty
         *     should be removed.
         */
        public ViolationInfo(Parcel in, boolean unsetGatheringBit) {
            mViolation = (Violation) in.readSerializable();
            int binderStackSize = in.readInt();
            for (int i = 0; i < binderStackSize; i++) {
                StackTraceElement[] traceElements = new StackTraceElement[in.readInt()];
                for (int j = 0; j < traceElements.length; j++) {
                    StackTraceElement element =
                            new StackTraceElement(
                                    in.readString(),
                                    in.readString(),
                                    in.readString(),
                                    in.readInt());
                    traceElements[j] = element;
                }
                mBinderStack.add(traceElements);
            }
            int rawPolicy = in.readInt();
            if (unsetGatheringBit) {
                mPolicy = rawPolicy & ~PENALTY_GATHER;
            } else {
                mPolicy = rawPolicy;
            }
            durationMillis = in.readInt();
            violationNumThisLoop = in.readInt();
            numAnimationsRunning = in.readInt();
            violationUptimeMillis = in.readLong();
            numInstances = in.readLong();
            broadcastIntentAction = in.readString();
            tags = in.readStringArray();
        }

        
Save a ViolationInfo instance to a parcel. /** Save a ViolationInfo instance to a parcel. */
        @Override
        public void writeToParcel(Parcel dest, int flags) {
            dest.writeSerializable(mViolation);
            dest.writeInt(mBinderStack.size());
            for (StackTraceElement[] traceElements : mBinderStack) {
                dest.writeInt(traceElements.length);
                for (StackTraceElement element : traceElements) {
                    dest.writeString(element.getClassName());
                    dest.writeString(element.getMethodName());
                    dest.writeString(element.getFileName());
                    dest.writeInt(element.getLineNumber());
                }
            }
            int start = dest.dataPosition();
            dest.writeInt(mPolicy);
            dest.writeInt(durationMillis);
            dest.writeInt(violationNumThisLoop);
            dest.writeInt(numAnimationsRunning);
            dest.writeLong(violationUptimeMillis);
            dest.writeLong(numInstances);
            dest.writeString(broadcastIntentAction);
            dest.writeStringArray(tags);
            int total = dest.dataPosition() - start;
            if (Binder.CHECK_PARCEL_SIZE && total > 10 * 1024) {
                Slog.d(
                        TAG,
                        "VIO: policy="
                                + mPolicy
                                + " dur="
                                + durationMillis
                                + " numLoop="
                                + violationNumThisLoop
                                + " anim="
                                + numAnimationsRunning
                                + " uptime="
                                + violationUptimeMillis
                                + " numInst="
                                + numInstances);
                Slog.d(TAG, "VIO: action=" + broadcastIntentAction);
                Slog.d(TAG, "VIO: tags=" + Arrays.toString(tags));
                Slog.d(TAG, "VIO: TOTAL BYTES WRITTEN: " + (dest.dataPosition() - start));
            }
        }

        
Dump a ViolationInfo instance to a Printer. /** Dump a ViolationInfo instance to a Printer. */
        public void dump(Printer pw, String prefix) {
            pw.println(prefix + "stackTrace: " + getStackTrace());
            pw.println(prefix + "policy: " + mPolicy);
            if (durationMillis != -1) {
                pw.println(prefix + "durationMillis: " + durationMillis);
            }
            if (numInstances != -1) {
                pw.println(prefix + "numInstances: " + numInstances);
            }
            if (violationNumThisLoop != 0) {
                pw.println(prefix + "violationNumThisLoop: " + violationNumThisLoop);
            }
            if (numAnimationsRunning != 0) {
                pw.println(prefix + "numAnimationsRunning: " + numAnimationsRunning);
            }
            pw.println(prefix + "violationUptimeMillis: " + violationUptimeMillis);
            if (broadcastIntentAction != null) {
                pw.println(prefix + "broadcastIntentAction: " + broadcastIntentAction);
            }
            if (tags != null) {
                int index = 0;
                for (String tag : tags) {
                    pw.println(prefix + "tag[" + (index++) + "]: " + tag);
                }
            }
        }

        @Override
        public int describeContents() {
            return 0;
        }

        public static final Parcelable.Creator<ViolationInfo> CREATOR =
                new Parcelable.Creator<ViolationInfo>() {
                    @Override
                    public ViolationInfo createFromParcel(Parcel in) {
                        return new ViolationInfo(in);
                    }

                    @Override
                    public ViolationInfo[] newArray(int size) {
                        return new ViolationInfo[size];
                    }
                };
    }

    private static final class InstanceTracker {
        private static final HashMap<Class<?>, Integer> sInstanceCounts =
                new HashMap<Class<?>, Integer>();

        private final Class<?> mKlass;

        public InstanceTracker(Object instance) {
            mKlass = instance.getClass();

            synchronized (sInstanceCounts) {
                final Integer value = sInstanceCounts.get(mKlass);
                final int newValue = value != null ? value + 1 : 1;
                sInstanceCounts.put(mKlass, newValue);
            }
        }

        @Override
        protected void finalize() throws Throwable {
            try {
                synchronized (sInstanceCounts) {
                    final Integer value = sInstanceCounts.get(mKlass);
                    if (value != null) {
                        final int newValue = value - 1;
                        if (newValue > 0) {
                            sInstanceCounts.put(mKlass, newValue);
                        } else {
                            sInstanceCounts.remove(mKlass);
                        }
                    }
                }
            } finally {
                super.finalize();
            }
        }

        public static int getInstanceCount(Class<?> klass) {
            synchronized (sInstanceCounts) {
                final Integer value = sInstanceCounts.get(klass);
                return value != null ? value : 0;
            }
        }
    }
}