https://source.android.com/ 
/*
 * Copyright (C) 2006 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.annotation.NonNull;
import android.annotation.Nullable;
import android.util.ExceptionUtils;
import android.util.Log;
import android.util.Slog;
import android.util.SparseIntArray;

import com.android.internal.os.BinderCallsStats;
import com.android.internal.os.BinderInternal;
import com.android.internal.util.FastPrintWriter;
import com.android.internal.util.FunctionalUtils.ThrowingRunnable;
import com.android.internal.util.FunctionalUtils.ThrowingSupplier;

import libcore.io.IoUtils;
import libcore.util.NativeAllocationRegistry;

import java.io.FileDescriptor;
import java.io.FileOutputStream;
import java.io.PrintWriter;
import java.lang.ref.WeakReference;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;


Base class for a remotable object, the core part of a lightweight remote procedure call mechanism defined by IBinder. This class is an implementation of IBinder that provides standard local implementation of such an object. 
Most developers will not implement this class directly, instead using the
aidl tool to describe the desired
interface, having it generate the appropriate Binder subclass.  You can,
however, derive directly from Binder to implement your own custom RPC
protocol or simply instantiate a raw Binder object directly to use as a
token that can be shared across processes.

This class is just a basic IPC primitive; it has no impact on an application's lifecycle, and is valid only as long as the process that created it continues to run. To use this correctly, you must be doing so within the context of a top-level application component (a Service, Activity, or ContentProvider) that lets the system know your process should remain running.


You must keep in mind the situations in which your process could go away, and thus require that you later re-create a new Binder and re-attach it when the process starts again. For example, if you are using this within an Activity, your activity's process may be killed any time the activity is not started; if the activity is later re-created you will need to create a new Binder and hand it back to the correct place again; you need to be aware that your process may be started for another reason (for example to receive a broadcast) that will not involve re-creating the activity and thus run its code to create a new Binder.


See Also:
/**
 * Base class for a remotable object, the core part of a lightweight
 * remote procedure call mechanism defined by {@link IBinder}.
 * This class is an implementation of IBinder that provides
 * standard local implementation of such an object.
 *
 * <p>Most developers will not implement this class directly, instead using the
 * <a href="{@docRoot}guide/components/aidl.html">aidl</a> tool to describe the desired
 * interface, having it generate the appropriate Binder subclass.  You can,
 * however, derive directly from Binder to implement your own custom RPC
 * protocol or simply instantiate a raw Binder object directly to use as a
 * token that can be shared across processes.
 *
 * <p>This class is just a basic IPC primitive; it has no impact on an application's
 * lifecycle, and is valid only as long as the process that created it continues to run.
 * To use this correctly, you must be doing so within the context of a top-level
 * application component (a {@link android.app.Service}, {@link android.app.Activity},
 * or {@link android.content.ContentProvider}) that lets the system know your process
 * should remain running.</p>
 *
 * <p>You must keep in mind the situations in which your process
 * could go away, and thus require that you later re-create a new Binder and re-attach
 * it when the process starts again.  For example, if you are using this within an
 * {@link android.app.Activity}, your activity's process may be killed any time the
 * activity is not started; if the activity is later re-created you will need to
 * create a new Binder and hand it back to the correct place again; you need to be
 * aware that your process may be started for another reason (for example to receive
 * a broadcast) that will not involve re-creating the activity and thus run its code
 * to create a new Binder.</p>
 *
 * @see IBinder
 */
public class Binder implements IBinder {
    /*
     * Set this flag to true to detect anonymous, local or member classes
     * that extend this Binder class and that are not static. These kind
     * of classes can potentially create leaks.
     */
    private static final boolean FIND_POTENTIAL_LEAKS = false;
    
@hide
/** @hide */
    public static final boolean CHECK_PARCEL_SIZE = false;
    static final String TAG = "Binder";

    
@hide
/** @hide */
    public static boolean LOG_RUNTIME_EXCEPTION = false; // DO NOT SUBMIT WITH TRUE

    
Control whether dump() calls are allowed.

/**
     * Control whether dump() calls are allowed.
     */
    private static volatile String sDumpDisabled = null;

    
Global transaction tracker instance for this process.

/**
     * Global transaction tracker instance for this process.
     */
    private static volatile TransactionTracker sTransactionTracker = null;

    
Guestimate of native memory associated with a Binder.

/**
     * Guestimate of native memory associated with a Binder.
     */
    private static final int NATIVE_ALLOCATION_SIZE = 500;

    private static native long getNativeFinalizer();

    // Use a Holder to allow static initialization of Binder in the boot image, and
    // possibly to avoid some initialization ordering issues.
    private static class NoImagePreloadHolder {
        public static final NativeAllocationRegistry sRegistry = new NativeAllocationRegistry(
                Binder.class.getClassLoader(), getNativeFinalizer(), NATIVE_ALLOCATION_SIZE);
    }

    // Transaction tracking code.

    
Flag indicating whether we should be tracing transact calls.

/**
     * Flag indicating whether we should be tracing transact calls.
     */
    private static volatile boolean sTracingEnabled = false;

    
Enable Binder IPC tracing.

@hide
/**
     * Enable Binder IPC tracing.
     *
     * @hide
     */
    public static void enableTracing() {
        sTracingEnabled = true;
    }

    
Disable Binder IPC tracing.

@hide
/**
     * Disable Binder IPC tracing.
     *
     * @hide
     */
    public static void disableTracing() {
        sTracingEnabled = false;
    }

    
Check if binder transaction tracing is enabled.

@hide
/**
     * Check if binder transaction tracing is enabled.
     *
     * @hide
     */
    public static boolean isTracingEnabled() {
        return sTracingEnabled;
    }

    
Get the binder transaction tracker for this process.

@hide
/**
     * Get the binder transaction tracker for this process.
     *
     * @hide
     */
    public synchronized static TransactionTracker getTransactionTracker() {
        if (sTransactionTracker == null)
            sTransactionTracker = new TransactionTracker();
        return sTransactionTracker;
    }

    
{@hide} 
/** {@hide} */
    static volatile boolean sWarnOnBlocking = false;

    
Warn if any blocking binder transactions are made out from this process. This is typically only useful for the system process, to prevent it from blocking on calls to external untrusted code. Instead, all outgoing calls that require a result must be sent as IBinder.FLAG_ONEWAY calls which deliver results through a callback interface. 
@hide
/**
     * Warn if any blocking binder transactions are made out from this process.
     * This is typically only useful for the system process, to prevent it from
     * blocking on calls to external untrusted code. Instead, all outgoing calls
     * that require a result must be sent as {@link IBinder#FLAG_ONEWAY} calls
     * which deliver results through a callback interface.
     *
     * @hide
     */
    public static void setWarnOnBlocking(boolean warnOnBlocking) {
        sWarnOnBlocking = warnOnBlocking;
    }

    
Allow blocking calls on the given interface, overriding the requested value of setWarnOnBlocking(boolean). 

This should only be rarely called when you are absolutely sure
the remote interface is a built-in system component that can never be
upgraded. In particular, this must never be called for
interfaces hosted by package that could be upgraded or replaced,
otherwise you risk system instability if that remote interface wedges.

@hide
/**
     * Allow blocking calls on the given interface, overriding the requested
     * value of {@link #setWarnOnBlocking(boolean)}.
     * <p>
     * This should only be rarely called when you are <em>absolutely sure</em>
     * the remote interface is a built-in system component that can never be
     * upgraded. In particular, this <em>must never</em> be called for
     * interfaces hosted by package that could be upgraded or replaced,
     * otherwise you risk system instability if that remote interface wedges.
     *
     * @hide
     */
    public static IBinder allowBlocking(IBinder binder) {
        try {
            if (binder instanceof BinderProxy) {
                ((BinderProxy) binder).mWarnOnBlocking = false;
            } else if (binder != null && binder.getInterfaceDescriptor() != null
                    && binder.queryLocalInterface(binder.getInterfaceDescriptor()) == null) {
                Log.w(TAG, "Unable to allow blocking on interface " + binder);
            }
        } catch (RemoteException ignored) {
        }
        return binder;
    }

    
Reset the given interface back to the default blocking behavior, reverting any changes made by allowBlocking(IBinder). 
@hide
/**
     * Reset the given interface back to the default blocking behavior,
     * reverting any changes made by {@link #allowBlocking(IBinder)}.
     *
     * @hide
     */
    public static IBinder defaultBlocking(IBinder binder) {
        if (binder instanceof BinderProxy) {
            ((BinderProxy) binder).mWarnOnBlocking = sWarnOnBlocking;
        }
        return binder;
    }

    
Inherit the current allowBlocking(IBinder) value from one given interface to another. 
@hide
/**
     * Inherit the current {@link #allowBlocking(IBinder)} value from one given
     * interface to another.
     *
     * @hide
     */
    public static void copyAllowBlocking(IBinder fromBinder, IBinder toBinder) {
        if (fromBinder instanceof BinderProxy && toBinder instanceof BinderProxy) {
            ((BinderProxy) toBinder).mWarnOnBlocking = ((BinderProxy) fromBinder).mWarnOnBlocking;
        }
    }

    
Raw native pointer to JavaBBinderHolder object. Owned by this Java object. Not null.

/**
     * Raw native pointer to JavaBBinderHolder object. Owned by this Java object. Not null.
     */
    private final long mObject;

    private IInterface mOwner;
    private String mDescriptor;

    
Return the ID of the process that sent you the current transaction
that is being processed.  This pid can be used with higher-level
system services to determine its identity and check permissions.
If the current thread is not currently executing an incoming transaction,
then its own pid is returned.

/**
     * Return the ID of the process that sent you the current transaction
     * that is being processed.  This pid can be used with higher-level
     * system services to determine its identity and check permissions.
     * If the current thread is not currently executing an incoming transaction,
     * then its own pid is returned.
     */
    public static final native int getCallingPid();

    
Return the Linux uid assigned to the process that sent you the
current transaction that is being processed.  This uid can be used with
higher-level system services to determine its identity and check
permissions.  If the current thread is not currently executing an
incoming transaction, then its own uid is returned.

/**
     * Return the Linux uid assigned to the process that sent you the
     * current transaction that is being processed.  This uid can be used with
     * higher-level system services to determine its identity and check
     * permissions.  If the current thread is not currently executing an
     * incoming transaction, then its own uid is returned.
     */
    public static final native int getCallingUid();

    
Return the UserHandle assigned to the process that sent you the current transaction that is being processed. This is the user of the caller. It is distinct from getCallingUid() in that a particular user will have multiple distinct apps running under it each with their own uid. If the current thread is not currently executing an incoming transaction, then its own UserHandle is returned. 
/**
     * Return the UserHandle assigned to the process that sent you the
     * current transaction that is being processed.  This is the user
     * of the caller.  It is distinct from {@link #getCallingUid()} in that a
     * particular user will have multiple distinct apps running under it each
     * with their own uid.  If the current thread is not currently executing an
     * incoming transaction, then its own UserHandle is returned.
     */
    public static final @NonNull UserHandle getCallingUserHandle() {
        return UserHandle.of(UserHandle.getUserId(getCallingUid()));
    }

    
Reset the identity of the incoming IPC on the current thread.  This can
be useful if, while handling an incoming call, you will be calling
on interfaces of other objects that may be local to your process and
need to do permission checks on the calls coming into them (so they
will check the permission of your own local process, and not whatever
process originally called you).

See Also:
Returns:Returns an opaque token that can be used to restore the original calling identity by passing it to restoreCallingIdentity(long).
/**
     * Reset the identity of the incoming IPC on the current thread.  This can
     * be useful if, while handling an incoming call, you will be calling
     * on interfaces of other objects that may be local to your process and
     * need to do permission checks on the calls coming into them (so they
     * will check the permission of your own local process, and not whatever
     * process originally called you).
     *
     * @return Returns an opaque token that can be used to restore the
     * original calling identity by passing it to
     * {@link #restoreCallingIdentity(long)}.
     *
     * @see #getCallingPid()
     * @see #getCallingUid()
     * @see #restoreCallingIdentity(long)
     */
    public static final native long clearCallingIdentity();

    
Restore the identity of the incoming IPC on the current thread back to a previously identity that was returned by clearCallingIdentity. 
Params:
See Also:
/**
     * Restore the identity of the incoming IPC on the current thread
     * back to a previously identity that was returned by {@link
     * #clearCallingIdentity}.
     *
     * @param token The opaque token that was previously returned by
     * {@link #clearCallingIdentity}.
     *
     * @see #clearCallingIdentity
     */
    public static final native void restoreCallingIdentity(long token);

    
Convenience method for running the provided action enclosed in clearCallingIdentity/restoreCallingIdentity Any exception thrown by the given action will be caught and rethrown after the call to restoreCallingIdentity 
@hide
/**
     * Convenience method for running the provided action enclosed in
     * {@link #clearCallingIdentity}/{@link #restoreCallingIdentity}
     *
     * Any exception thrown by the given action will be caught and rethrown after the call to
     * {@link #restoreCallingIdentity}
     *
     * @hide
     */
    public static final void withCleanCallingIdentity(@NonNull ThrowingRunnable action) {
        long callingIdentity = clearCallingIdentity();
        Throwable throwableToPropagate = null;
        try {
            action.runOrThrow();
        } catch (Throwable throwable) {
            throwableToPropagate = throwable;
        } finally {
            restoreCallingIdentity(callingIdentity);
            if (throwableToPropagate != null) {
                throw ExceptionUtils.propagate(throwableToPropagate);
            }
        }
    }

    
Convenience method for running the provided action enclosed in clearCallingIdentity/restoreCallingIdentity returning the result Any exception thrown by the given action will be caught and rethrown after the call to restoreCallingIdentity 
@hide
/**
     * Convenience method for running the provided action enclosed in
     * {@link #clearCallingIdentity}/{@link #restoreCallingIdentity} returning the result
     *
     * Any exception thrown by the given action will be caught and rethrown after the call to
     * {@link #restoreCallingIdentity}
     *
     * @hide
     */
    public static final <T> T withCleanCallingIdentity(@NonNull ThrowingSupplier<T> action) {
        long callingIdentity = clearCallingIdentity();
        Throwable throwableToPropagate = null;
        try {
            return action.getOrThrow();
        } catch (Throwable throwable) {
            throwableToPropagate = throwable;
            return null; // overridden by throwing in finally block
        } finally {
            restoreCallingIdentity(callingIdentity);
            if (throwableToPropagate != null) {
                throw ExceptionUtils.propagate(throwableToPropagate);
            }
        }
    }

    
Sets the native thread-local StrictMode policy mask.

The StrictMode settings are kept in two places: a Java-level
threadlocal for libcore/Dalvik, and a native threadlocal (set
here) for propagation via Binder calls.  This is a little
unfortunate, but necessary to break otherwise more unfortunate
dependencies either of Dalvik on Android, or Android
native-only code on Dalvik.

See Also:
  • StrictMode
@hide
/**
     * Sets the native thread-local StrictMode policy mask.
     *
     * <p>The StrictMode settings are kept in two places: a Java-level
     * threadlocal for libcore/Dalvik, and a native threadlocal (set
     * here) for propagation via Binder calls.  This is a little
     * unfortunate, but necessary to break otherwise more unfortunate
     * dependencies either of Dalvik on Android, or Android
     * native-only code on Dalvik.
     *
     * @see StrictMode
     * @hide
     */
    public static final native void setThreadStrictModePolicy(int policyMask);

    
Gets the current native thread-local StrictMode policy mask.

See Also:
  • setThreadStrictModePolicy
@hide
/**
     * Gets the current native thread-local StrictMode policy mask.
     *
     * @see #setThreadStrictModePolicy
     * @hide
     */
    public static final native int getThreadStrictModePolicy();

    
Flush any Binder commands pending in the current thread to the kernel
driver.  This can be
useful to call before performing an operation that may block for a long
time, to ensure that any pending object references have been released
in order to prevent the process from holding on to objects longer than
it needs to.

/**
     * Flush any Binder commands pending in the current thread to the kernel
     * driver.  This can be
     * useful to call before performing an operation that may block for a long
     * time, to ensure that any pending object references have been released
     * in order to prevent the process from holding on to objects longer than
     * it needs to.
     */
    public static final native void flushPendingCommands();

    
Add the calling thread to the IPC thread pool.  This function does
not return until the current process is exiting.

/**
     * Add the calling thread to the IPC thread pool.  This function does
     * not return until the current process is exiting.
     */
    public static final void joinThreadPool() {
        BinderInternal.joinThreadPool();
    }

    
Returns true if the specified interface is a proxy.

@hide
/**
     * Returns true if the specified interface is a proxy.
     * @hide
     */
    public static final boolean isProxy(IInterface iface) {
        return iface.asBinder() != iface;
    }

    
Call blocks until the number of executing binder threads is less
than the maximum number of binder threads allowed for this process.

@hide
/**
     * Call blocks until the number of executing binder threads is less
     * than the maximum number of binder threads allowed for this process.
     * @hide
     */
    public static final native void blockUntilThreadAvailable();

    
Default constructor initializes the object.

/**
     * Default constructor initializes the object.
     */
    public Binder() {
        mObject = getNativeBBinderHolder();
        NoImagePreloadHolder.sRegistry.registerNativeAllocation(this, mObject);

        if (FIND_POTENTIAL_LEAKS) {
            final Class<? extends Binder> klass = getClass();
            if ((klass.isAnonymousClass() || klass.isMemberClass() || klass.isLocalClass()) &&
                    (klass.getModifiers() & Modifier.STATIC) == 0) {
                Log.w(TAG, "The following Binder class should be static or leaks might occur: " +
                    klass.getCanonicalName());
            }
        }
    }

    
Convenience method for associating a specific interface with the Binder.
After calling, queryLocalInterface() will be implemented for you
to return the given owner IInterface when the corresponding
descriptor is requested.

/**
     * Convenience method for associating a specific interface with the Binder.
     * After calling, queryLocalInterface() will be implemented for you
     * to return the given owner IInterface when the corresponding
     * descriptor is requested.
     */
    public void attachInterface(@Nullable IInterface owner, @Nullable String descriptor) {
        mOwner = owner;
        mDescriptor = descriptor;
    }

    
Default implementation returns an empty interface name.

/**
     * Default implementation returns an empty interface name.
     */
    public @Nullable String getInterfaceDescriptor() {
        return mDescriptor;
    }

    
Default implementation always returns true -- if you got here,
the object is alive.

/**
     * Default implementation always returns true -- if you got here,
     * the object is alive.
     */
    public boolean pingBinder() {
        return true;
    }

    
{@inheritDoc}
Note that if you're calling on a local binder, this always returns true
because your process is alive if you're calling it.

/**
     * {@inheritDoc}
     *
     * Note that if you're calling on a local binder, this always returns true
     * because your process is alive if you're calling it.
     */
    public boolean isBinderAlive() {
        return true;
    }

    
Use information supplied to attachInterface() to return the
associated IInterface if it matches the requested
descriptor.

/**
     * Use information supplied to attachInterface() to return the
     * associated IInterface if it matches the requested
     * descriptor.
     */
    public @Nullable IInterface queryLocalInterface(@NonNull String descriptor) {
        if (mDescriptor != null && mDescriptor.equals(descriptor)) {
            return mOwner;
        }
        return null;
    }

    
Control disabling of dump calls in this process.  This is used by the system
process watchdog to disable incoming dump calls while it has detecting the system
is hung and is reporting that back to the activity controller.  This is to
prevent the controller from getting hung up on bug reports at this point.

Params:
  • msg – The message to show instead of the dump; if null, dumps are
re-enabled.
@hide
/**
     * Control disabling of dump calls in this process.  This is used by the system
     * process watchdog to disable incoming dump calls while it has detecting the system
     * is hung and is reporting that back to the activity controller.  This is to
     * prevent the controller from getting hung up on bug reports at this point.
     * @hide
     *
     * @param msg The message to show instead of the dump; if null, dumps are
     * re-enabled.
     */
    public static void setDumpDisabled(String msg) {
        sDumpDisabled = msg;
    }

    
Default implementation is a stub that returns false.  You will want
to override this to do the appropriate unmarshalling of transactions.

If you want to call this, call transact().

Implementations that are returning a result should generally use Parcel.writeNoException and Parcel.writeException to propagate exceptions back to the caller.


Params:
Returns:Return true on a successful call; returning false is generally used to
indicate that you did not understand the transaction code.
/**
     * Default implementation is a stub that returns false.  You will want
     * to override this to do the appropriate unmarshalling of transactions.
     *
     * <p>If you want to call this, call transact().
     *
     * <p>Implementations that are returning a result should generally use
     * {@link Parcel#writeNoException() Parcel.writeNoException} and
     * {@link Parcel#writeException(Exception) Parcel.writeException} to propagate
     * exceptions back to the caller.</p>
     *
     * @param code The action to perform.  This should
     * be a number between {@link #FIRST_CALL_TRANSACTION} and
     * {@link #LAST_CALL_TRANSACTION}.
     * @param data Marshalled data being received from the caller.
     * @param reply If the caller is expecting a result back, it should be marshalled
     * in to here.
     * @param flags Additional operation flags.  Either 0 for a normal
     * RPC, or {@link #FLAG_ONEWAY} for a one-way RPC.
     *
     * @return Return true on a successful call; returning false is generally used to
     * indicate that you did not understand the transaction code.
     */
    protected boolean onTransact(int code, @NonNull Parcel data, @Nullable Parcel reply,
            int flags) throws RemoteException {
        if (code == INTERFACE_TRANSACTION) {
            reply.writeString(getInterfaceDescriptor());
            return true;
        } else if (code == DUMP_TRANSACTION) {
            ParcelFileDescriptor fd = data.readFileDescriptor();
            String[] args = data.readStringArray();
            if (fd != null) {
                try {
                    dump(fd.getFileDescriptor(), args);
                } finally {
                    IoUtils.closeQuietly(fd);
                }
            }
            // Write the StrictMode header.
            if (reply != null) {
                reply.writeNoException();
            } else {
                StrictMode.clearGatheredViolations();
            }
            return true;
        } else if (code == SHELL_COMMAND_TRANSACTION) {
            ParcelFileDescriptor in = data.readFileDescriptor();
            ParcelFileDescriptor out = data.readFileDescriptor();
            ParcelFileDescriptor err = data.readFileDescriptor();
            String[] args = data.readStringArray();
            ShellCallback shellCallback = ShellCallback.CREATOR.createFromParcel(data);
            ResultReceiver resultReceiver = ResultReceiver.CREATOR.createFromParcel(data);
            try {
                if (out != null) {
                    shellCommand(in != null ? in.getFileDescriptor() : null,
                            out.getFileDescriptor(),
                            err != null ? err.getFileDescriptor() : out.getFileDescriptor(),
                            args, shellCallback, resultReceiver);
                }
            } finally {
                IoUtils.closeQuietly(in);
                IoUtils.closeQuietly(out);
                IoUtils.closeQuietly(err);
                // Write the StrictMode header.
                if (reply != null) {
                    reply.writeNoException();
                } else {
                    StrictMode.clearGatheredViolations();
                }
            }
            return true;
        }
        return false;
    }

    
Implemented to call the more convenient version dump(FileDescriptor, PrintWriter, String[]). 
/**
     * Implemented to call the more convenient version
     * {@link #dump(FileDescriptor, PrintWriter, String[])}.
     */
    public void dump(@NonNull FileDescriptor fd, @Nullable String[] args) {
        FileOutputStream fout = new FileOutputStream(fd);
        PrintWriter pw = new FastPrintWriter(fout);
        try {
            doDump(fd, pw, args);
        } finally {
            pw.flush();
        }
    }

    void doDump(FileDescriptor fd, PrintWriter pw, String[] args) {
        final String disabled = sDumpDisabled;
        if (disabled == null) {
            try {
                dump(fd, pw, args);
            } catch (SecurityException e) {
                pw.println("Security exception: " + e.getMessage());
                throw e;
            } catch (Throwable e) {
                // Unlike usual calls, in this case if an exception gets thrown
                // back to us we want to print it back in to the dump data, since
                // that is where the caller expects all interesting information to
                // go.
                pw.println();
                pw.println("Exception occurred while dumping:");
                e.printStackTrace(pw);
            }
        } else {
            pw.println(sDumpDisabled);
        }
    }

    
Like dump(FileDescriptor, String[]), but ensures the target executes asynchronously. 
/**
     * Like {@link #dump(FileDescriptor, String[])}, but ensures the target
     * executes asynchronously.
     */
    public void dumpAsync(@NonNull final FileDescriptor fd, @Nullable final String[] args) {
        final FileOutputStream fout = new FileOutputStream(fd);
        final PrintWriter pw = new FastPrintWriter(fout);
        Thread thr = new Thread("Binder.dumpAsync") {
            public void run() {
                try {
                    dump(fd, pw, args);
                } finally {
                    pw.flush();
                }
            }
        };
        thr.start();
    }

    
Print the object's state into the given stream.

Params:
  • fd – The raw file descriptor that the dump is being sent to.
  • fout – The file to which you should dump your state.  This will be
closed for you after you return.
  • args – additional arguments to the dump request.
/**
     * Print the object's state into the given stream.
     * 
     * @param fd The raw file descriptor that the dump is being sent to.
     * @param fout The file to which you should dump your state.  This will be
     * closed for you after you return.
     * @param args additional arguments to the dump request.
     */
    protected void dump(@NonNull FileDescriptor fd, @NonNull PrintWriter fout,
            @Nullable String[] args) {
    }

    
Params:
  • in – The raw file descriptor that an input data stream can be read from.
  • out – The raw file descriptor that normal command messages should be written to.
  • err – The raw file descriptor that command error messages should be written to.
  • args – Command-line arguments.
  • callback – Callback through which to interact with the invoking shell.
  • resultReceiver – Called when the command has finished executing, with the result code.
Throws:
@hide
/**
     * @param in The raw file descriptor that an input data stream can be read from.
     * @param out The raw file descriptor that normal command messages should be written to.
     * @param err The raw file descriptor that command error messages should be written to.
     * @param args Command-line arguments.
     * @param callback Callback through which to interact with the invoking shell.
     * @param resultReceiver Called when the command has finished executing, with the result code.
     * @throws RemoteException
     * @hide
     */
    public void shellCommand(@Nullable FileDescriptor in, @Nullable FileDescriptor out,
            @Nullable FileDescriptor err,
            @NonNull String[] args, @Nullable ShellCallback callback,
            @NonNull ResultReceiver resultReceiver) throws RemoteException {
        onShellCommand(in, out, err, args, callback, resultReceiver);
    }

    
Handle a call to shellCommand. The default implementation simply prints an error message. Override and replace with your own. 
Note: no permission checking is done before calling this method; you must apply any security checks as appropriate for the command being executed. Consider using ShellCommand to help in the implementation.


@hide
/**
     * Handle a call to {@link #shellCommand}.  The default implementation simply prints
     * an error message.  Override and replace with your own.
     * <p class="caution">Note: no permission checking is done before calling this method; you must
     * apply any security checks as appropriate for the command being executed.
     * Consider using {@link ShellCommand} to help in the implementation.</p>
     * @hide
     */
    public void onShellCommand(@Nullable FileDescriptor in, @Nullable FileDescriptor out,
            @Nullable FileDescriptor err,
            @NonNull String[] args, @Nullable ShellCallback callback,
            @NonNull ResultReceiver resultReceiver) throws RemoteException {
        FileOutputStream fout = new FileOutputStream(err != null ? err : out);
        PrintWriter pw = new FastPrintWriter(fout);
        pw.println("No shell command implementation.");
        pw.flush();
        resultReceiver.send(0, null);
    }

    
Default implementation rewinds the parcels and calls onTransact.  On
the remote side, transact calls into the binder to do the IPC.

/**
     * Default implementation rewinds the parcels and calls onTransact.  On
     * the remote side, transact calls into the binder to do the IPC.
     */
    public final boolean transact(int code, @NonNull Parcel data, @Nullable Parcel reply,
            int flags) throws RemoteException {
        if (false) Log.v("Binder", "Transact: " + code + " to " + this);

        if (data != null) {
            data.setDataPosition(0);
        }
        boolean r = onTransact(code, data, reply, flags);
        if (reply != null) {
            reply.setDataPosition(0);
        }
        return r;
    }

    
Local implementation is a no-op.

/**
     * Local implementation is a no-op.
     */
    public void linkToDeath(@NonNull DeathRecipient recipient, int flags) {
    }

    
Local implementation is a no-op.

/**
     * Local implementation is a no-op.
     */
    public boolean unlinkToDeath(@NonNull DeathRecipient recipient, int flags) {
        return true;
    }

    static void checkParcel(IBinder obj, int code, Parcel parcel, String msg) {
        if (CHECK_PARCEL_SIZE && parcel.dataSize() >= 800*1024) {
            // Trying to send > 800k, this is way too much
            StringBuilder sb = new StringBuilder();
            sb.append(msg);
            sb.append(": on ");
            sb.append(obj);
            sb.append(" calling ");
            sb.append(code);
            sb.append(" size ");
            sb.append(parcel.dataSize());
            sb.append(" (data: ");
            parcel.setDataPosition(0);
            sb.append(parcel.readInt());
            sb.append(", ");
            sb.append(parcel.readInt());
            sb.append(", ");
            sb.append(parcel.readInt());
            sb.append(")");
            Slog.wtfStack(TAG, sb.toString());
        }
    }

    private static native long getNativeBBinderHolder();
    private static native long getFinalizer();

    // Entry point from android_util_Binder.cpp's onTransact
    private boolean execTransact(int code, long dataObj, long replyObj,
            int flags) {
        BinderCallsStats binderCallsStats = BinderCallsStats.getInstance();
        BinderCallsStats.CallSession callSession = binderCallsStats.callStarted(this, code);
        Parcel data = Parcel.obtain(dataObj);
        Parcel reply = Parcel.obtain(replyObj);
        // theoretically, we should call transact, which will call onTransact,
        // but all that does is rewind it, and we just got these from an IPC,
        // so we'll just call it directly.
        boolean res;
        // Log any exceptions as warnings, don't silently suppress them.
        // If the call was FLAG_ONEWAY then these exceptions disappear into the ether.
        final boolean tracingEnabled = Binder.isTracingEnabled();
        try {
            if (tracingEnabled) {
                Trace.traceBegin(Trace.TRACE_TAG_ALWAYS, getClass().getName() + ":" + code);
            }
            res = onTransact(code, data, reply, flags);
        } catch (RemoteException|RuntimeException e) {
            if (LOG_RUNTIME_EXCEPTION) {
                Log.w(TAG, "Caught a RuntimeException from the binder stub implementation.", e);
            }
            if ((flags & FLAG_ONEWAY) != 0) {
                if (e instanceof RemoteException) {
                    Log.w(TAG, "Binder call failed.", e);
                } else {
                    Log.w(TAG, "Caught a RuntimeException from the binder stub implementation.", e);
                }
            } else {
                reply.setDataPosition(0);
                reply.writeException(e);
            }
            res = true;
        } finally {
            if (tracingEnabled) {
                Trace.traceEnd(Trace.TRACE_TAG_ALWAYS);
            }
        }
        checkParcel(this, code, reply, "Unreasonably large binder reply buffer");
        reply.recycle();
        data.recycle();

        // Just in case -- we are done with the IPC, so there should be no more strict
        // mode violations that have gathered for this thread.  Either they have been
        // parceled and are now in transport off to the caller, or we are returning back
        // to the main transaction loop to wait for another incoming transaction.  Either
        // way, strict mode begone!
        StrictMode.clearGatheredViolations();
        binderCallsStats.callEnded(callSession);

        return res;
    }
}


Java proxy for a native IBinder object.
Allocated and constructed by the native javaObjectforIBinder function. Never allocated
directly from Java code.

/**
 * Java proxy for a native IBinder object.
 * Allocated and constructed by the native javaObjectforIBinder function. Never allocated
 * directly from Java code.
 */
final class BinderProxy implements IBinder {
    // See android_util_Binder.cpp for the native half of this.

    // Assume the process-wide default value when created
    volatile boolean mWarnOnBlocking = Binder.sWarnOnBlocking;

    /*
     * Map from longs to BinderProxy, retaining only a WeakReference to the BinderProxies.
     * We roll our own only because we need to lazily remove WeakReferences during accesses
     * to avoid accumulating junk WeakReference objects. WeakHashMap isn't easily usable
     * because we want weak values, not keys.
     * Our hash table is never resized, but the number of entries is unlimited;
     * performance degrades as occupancy increases significantly past MAIN_INDEX_SIZE.
     * Not thread-safe. Client ensures there's a single access at a time.
     */
    private static final class ProxyMap {
        private static final int LOG_MAIN_INDEX_SIZE = 8;
        private static final int MAIN_INDEX_SIZE = 1 <<  LOG_MAIN_INDEX_SIZE;
        private static final int MAIN_INDEX_MASK = MAIN_INDEX_SIZE - 1;
        // Debuggable builds will throw an AssertionError if the number of map entries exceeds:
        private static final int CRASH_AT_SIZE = 20_000;

        
We next warn when we exceed this bucket size.

/**
         * We next warn when we exceed this bucket size.
         */
        private int mWarnBucketSize = 20;

        
Increment mWarnBucketSize by WARN_INCREMENT each time we warn.

/**
         * Increment mWarnBucketSize by WARN_INCREMENT each time we warn.
         */
        private static final int WARN_INCREMENT = 10;

        
Hash function tailored to native pointers.
Returns a value < MAIN_INDEX_SIZE.

/**
         * Hash function tailored to native pointers.
         * Returns a value < MAIN_INDEX_SIZE.
         */
        private static int hash(long arg) {
            return ((int) ((arg >> 2) ^ (arg >> (2 + LOG_MAIN_INDEX_SIZE)))) & MAIN_INDEX_MASK;
        }

        
Return the total number of pairs in the map.

/**
         * Return the total number of pairs in the map.
         */
        private int size() {
            int size = 0;
            for (ArrayList<WeakReference<BinderProxy>> a : mMainIndexValues) {
                if (a != null) {
                    size += a.size();
                }
            }
            return size;
        }

        
Return the total number of pairs in the map containing values that have
not been cleared. More expensive than the above size function.

/**
         * Return the total number of pairs in the map containing values that have
         * not been cleared. More expensive than the above size function.
         */
        private int unclearedSize() {
            int size = 0;
            for (ArrayList<WeakReference<BinderProxy>> a : mMainIndexValues) {
                if (a != null) {
                    for (WeakReference<BinderProxy> ref : a) {
                        if (ref.get() != null) {
                            ++size;
                        }
                    }
                }
            }
            return size;
        }

        
Remove ith entry from the hash bucket indicated by hash.

/**
         * Remove ith entry from the hash bucket indicated by hash.
         */
        private void remove(int hash, int index) {
            Long[] keyArray = mMainIndexKeys[hash];
            ArrayList<WeakReference<BinderProxy>> valueArray = mMainIndexValues[hash];
            int size = valueArray.size();  // KeyArray may have extra elements.
            // Move last entry into empty slot, and truncate at end.
            if (index != size - 1) {
                keyArray[index] = keyArray[size - 1];
                valueArray.set(index, valueArray.get(size - 1));
            }
            valueArray.remove(size - 1);
            // Just leave key array entry; it's unused. We only trust the valueArray size.
        }

        
Look up the supplied key. If we have a non-cleared entry for it, return it.

/**
         * Look up the supplied key. If we have a non-cleared entry for it, return it.
         */
        BinderProxy get(long key) {
            int myHash = hash(key);
            Long[] keyArray = mMainIndexKeys[myHash];
            if (keyArray == null) {
                return null;
            }
            ArrayList<WeakReference<BinderProxy>> valueArray = mMainIndexValues[myHash];
            int bucketSize = valueArray.size();
            for (int i = 0; i < bucketSize; ++i) {
                long foundKey = keyArray[i];
                if (key == foundKey) {
                    WeakReference<BinderProxy> wr = valueArray.get(i);
                    BinderProxy bp = wr.get();
                    if (bp != null) {
                        return bp;
                    } else {
                        remove(myHash, i);
                        return null;
                    }
                }
            }
            return null;
        }

        private int mRandom;  // A counter used to generate a "random" index. World's 2nd worst RNG.

        
Add the key-value pair to the map.
Requires that the indicated key is not already in the map.

/**
         * Add the key-value pair to the map.
         * Requires that the indicated key is not already in the map.
         */
        void set(long key, @NonNull BinderProxy value) {
            int myHash = hash(key);
            ArrayList<WeakReference<BinderProxy>> valueArray = mMainIndexValues[myHash];
            if (valueArray == null) {
                valueArray = mMainIndexValues[myHash] = new ArrayList<>();
                mMainIndexKeys[myHash] = new Long[1];
            }
            int size = valueArray.size();
            WeakReference<BinderProxy> newWr = new WeakReference<>(value);
            // First look for a cleared reference.
            // This ensures that ArrayList size is bounded by the maximum occupancy of
            // that bucket.
            for (int i = 0; i < size; ++i) {
                if (valueArray.get(i).get() == null) {
                    valueArray.set(i, newWr);
                    Long[] keyArray = mMainIndexKeys[myHash];
                    keyArray[i] = key;
                    if (i < size - 1) {
                        // "Randomly" check one of the remaining entries in [i+1, size), so that
                        // needlessly long buckets are eventually pruned.
                        int rnd = Math.floorMod(++mRandom, size - (i + 1));
                        if (valueArray.get(i + 1 + rnd).get() == null) {
                            remove(myHash, i + 1 + rnd);
                        }
                    }
                    return;
                }
            }
            valueArray.add(size, newWr);
            Long[] keyArray = mMainIndexKeys[myHash];
            if (keyArray.length == size) {
                // size >= 1, since we initially allocated one element
                Long[] newArray = new Long[size + size / 2 + 2];
                System.arraycopy(keyArray, 0, newArray, 0, size);
                newArray[size] = key;
                mMainIndexKeys[myHash] = newArray;
            } else {
                keyArray[size] = key;
            }
            if (size >= mWarnBucketSize) {
                final int totalSize = size();
                Log.v(Binder.TAG, "BinderProxy map growth! bucket size = " + size
                        + " total = " + totalSize);
                mWarnBucketSize += WARN_INCREMENT;
                if (Build.IS_DEBUGGABLE && totalSize >= CRASH_AT_SIZE) {
                    // Use the number of uncleared entries to determine whether we should
                    // really report a histogram and crash. We don't want to fundamentally
                    // change behavior for a debuggable process, so we GC only if we are
                    // about to crash.
                    final int totalUnclearedSize = unclearedSize();
                    if (totalUnclearedSize >= CRASH_AT_SIZE) {
                        dumpProxyInterfaceCounts();
                        dumpPerUidProxyCounts();
                        Runtime.getRuntime().gc();
                        throw new AssertionError("Binder ProxyMap has too many entries: "
                                + totalSize + " (total), " + totalUnclearedSize + " (uncleared), "
                                + unclearedSize() + " (uncleared after GC). BinderProxy leak?");
                    } else if (totalSize > 3 * totalUnclearedSize / 2) {
                        Log.v(Binder.TAG, "BinderProxy map has many cleared entries: "
                                + (totalSize - totalUnclearedSize) + " of " + totalSize
                                + " are cleared");
                    }
                }
            }
        }

        
Dump a histogram to the logcat. Used to diagnose abnormally large proxy maps.

/**
         * Dump a histogram to the logcat. Used to diagnose abnormally large proxy maps.
         */
        private void dumpProxyInterfaceCounts() {
            Map<String, Integer> counts = new HashMap<>();
            for (ArrayList<WeakReference<BinderProxy>> a : mMainIndexValues) {
                if (a != null) {
                    for (WeakReference<BinderProxy> weakRef : a) {
                        BinderProxy bp = weakRef.get();
                        String key;
                        if (bp == null) {
                            key = "<cleared weak-ref>";
                        } else {
                            try {
                                key = bp.getInterfaceDescriptor();
                            } catch (Throwable t) {
                                key = "<exception during getDescriptor>";
                            }
                        }
                        Integer i = counts.get(key);
                        if (i == null) {
                            counts.put(key, 1);
                        } else {
                            counts.put(key, i + 1);
                        }
                    }
                }
            }
            Map.Entry<String, Integer>[] sorted = counts.entrySet().toArray(
                    new Map.Entry[counts.size()]);
            Arrays.sort(sorted, (Map.Entry<String, Integer> a, Map.Entry<String, Integer> b)
                    -> b.getValue().compareTo(a.getValue()));
            Log.v(Binder.TAG, "BinderProxy descriptor histogram (top ten):");
            int printLength = Math.min(10, sorted.length);
            for (int i = 0; i < printLength; i++) {
                Log.v(Binder.TAG, " #" + (i + 1) + ": " + sorted[i].getKey() + " x"
                        + sorted[i].getValue());
            }
        }

        
Dump per uid binder proxy counts to the logcat.

/**
         * Dump per uid binder proxy counts to the logcat.
         */
        private void dumpPerUidProxyCounts() {
            SparseIntArray counts = BinderInternal.nGetBinderProxyPerUidCounts();
            if (counts.size() == 0) return;
            Log.d(Binder.TAG, "Per Uid Binder Proxy Counts:");
            for (int i = 0; i < counts.size(); i++) {
                final int uid = counts.keyAt(i);
                final int binderCount = counts.valueAt(i);
                Log.d(Binder.TAG, "UID : " + uid + "  count = " + binderCount);
            }
        }

        // Corresponding ArrayLists in the following two arrays always have the same size.
        // They contain no empty entries. However WeakReferences in the values ArrayLists
        // may have been cleared.

        // mMainIndexKeys[i][j] corresponds to mMainIndexValues[i].get(j) .
        // The values ArrayList has the proper size(), the corresponding keys array
        // is always at least the same size, but may be larger.
        // If either a particular keys array, or the corresponding values ArrayList
        // are null, then they both are.
        private final Long[][] mMainIndexKeys = new Long[MAIN_INDEX_SIZE][];
        private final ArrayList<WeakReference<BinderProxy>>[] mMainIndexValues =
                new ArrayList[MAIN_INDEX_SIZE];
    }

    private static ProxyMap sProxyMap = new ProxyMap();

    
Dump proxy debug information. Note: this method is not thread-safe; callers must serialize with other accesses to sProxyMap, in particular getInstance(long, long). 
@hide
/**
      * Dump proxy debug information.
      *
      * Note: this method is not thread-safe; callers must serialize with other
      * accesses to sProxyMap, in particular {@link #getInstance(long, long)}.
      *
      * @hide
      */
    private static void dumpProxyDebugInfo() {
        if (Build.IS_DEBUGGABLE) {
            sProxyMap.dumpProxyInterfaceCounts();
            // Note that we don't call dumpPerUidProxyCounts(); this is because this
            // method may be called as part of the uid limit being hit, and calling
            // back into the UID tracking code would cause us to try to acquire a mutex
            // that is held during that callback.
        }
    }

    
Return a BinderProxy for IBinder.
This method is thread-hostile!  The (native) caller serializes getInstance() calls using
gProxyLock.
If we previously returned a BinderProxy bp for the same iBinder, and bp is still
in use, then we return the same bp.

Params:
  • nativeData – C++ pointer to (possibly still empty) BinderProxyNativeData.
Takes ownership of nativeData iff .mNativeData == nativeData, or if
we exit via an exception.  If neither applies, it's the callers responsibility to
recycle nativeData.
  • iBinder – C++ pointer to IBinder. Does not take ownership of referenced object.
/**
     * Return a BinderProxy for IBinder.
     * This method is thread-hostile!  The (native) caller serializes getInstance() calls using
     * gProxyLock.
     * If we previously returned a BinderProxy bp for the same iBinder, and bp is still
     * in use, then we return the same bp.
     *
     * @param nativeData C++ pointer to (possibly still empty) BinderProxyNativeData.
     * Takes ownership of nativeData iff <result>.mNativeData == nativeData, or if
     * we exit via an exception.  If neither applies, it's the callers responsibility to
     * recycle nativeData.
     * @param iBinder C++ pointer to IBinder. Does not take ownership of referenced object.
     */
    private static BinderProxy getInstance(long nativeData, long iBinder) {
        BinderProxy result;
        try {
            result = sProxyMap.get(iBinder);
            if (result != null) {
                return result;
            }
            result = new BinderProxy(nativeData);
        } catch (Throwable e) {
            // We're throwing an exception (probably OOME); don't drop nativeData.
            NativeAllocationRegistry.applyFreeFunction(NoImagePreloadHolder.sNativeFinalizer,
                    nativeData);
            throw e;
        }
        NoImagePreloadHolder.sRegistry.registerNativeAllocation(result, nativeData);
        // The registry now owns nativeData, even if registration threw an exception.
        sProxyMap.set(iBinder, result);
        return result;
    }

    private BinderProxy(long nativeData) {
        mNativeData = nativeData;
    }

    
Guestimate of native memory associated with a BinderProxy.
This includes the underlying IBinder, associated DeathRecipientList, and KeyedVector
that points back to us. We guess high since it includes a GlobalRef, which
may be in short supply.

/**
     * Guestimate of native memory associated with a BinderProxy.
     * This includes the underlying IBinder, associated DeathRecipientList, and KeyedVector
     * that points back to us. We guess high since it includes a GlobalRef, which
     * may be in short supply.
     */
    private static final int NATIVE_ALLOCATION_SIZE = 1000;

    // Use a Holder to allow static initialization of BinderProxy in the boot image, and
    // to avoid some initialization ordering issues.
    private static class NoImagePreloadHolder {
        public static final long sNativeFinalizer = getNativeFinalizer();
        public static final NativeAllocationRegistry sRegistry = new NativeAllocationRegistry(
                BinderProxy.class.getClassLoader(), sNativeFinalizer, NATIVE_ALLOCATION_SIZE);
    }

    public native boolean pingBinder();
    public native boolean isBinderAlive();

    public IInterface queryLocalInterface(String descriptor) {
        return null;
    }

    public boolean transact(int code, Parcel data, Parcel reply, int flags) throws RemoteException {
        Binder.checkParcel(this, code, data, "Unreasonably large binder buffer");

        if (mWarnOnBlocking && ((flags & FLAG_ONEWAY) == 0)) {
            // For now, avoid spamming the log by disabling after we've logged
            // about this interface at least once
            mWarnOnBlocking = false;
            Log.w(Binder.TAG, "Outgoing transactions from this process must be FLAG_ONEWAY",
                    new Throwable());
        }

        final boolean tracingEnabled = Binder.isTracingEnabled();
        if (tracingEnabled) {
            final Throwable tr = new Throwable();
            Binder.getTransactionTracker().addTrace(tr);
            StackTraceElement stackTraceElement = tr.getStackTrace()[1];
            Trace.traceBegin(Trace.TRACE_TAG_ALWAYS,
                    stackTraceElement.getClassName() + "." + stackTraceElement.getMethodName());
        }
        try {
            return transactNative(code, data, reply, flags);
        } finally {
            if (tracingEnabled) {
                Trace.traceEnd(Trace.TRACE_TAG_ALWAYS);
            }
        }
    }

    private static native long getNativeFinalizer();
    public native String getInterfaceDescriptor() throws RemoteException;
    public native boolean transactNative(int code, Parcel data, Parcel reply,
            int flags) throws RemoteException;
    public native void linkToDeath(DeathRecipient recipient, int flags)
            throws RemoteException;
    public native boolean unlinkToDeath(DeathRecipient recipient, int flags);

    public void dump(FileDescriptor fd, String[] args) throws RemoteException {
        Parcel data = Parcel.obtain();
        Parcel reply = Parcel.obtain();
        data.writeFileDescriptor(fd);
        data.writeStringArray(args);
        try {
            transact(DUMP_TRANSACTION, data, reply, 0);
            reply.readException();
        } finally {
            data.recycle();
            reply.recycle();
        }
    }

    public void dumpAsync(FileDescriptor fd, String[] args) throws RemoteException {
        Parcel data = Parcel.obtain();
        Parcel reply = Parcel.obtain();
        data.writeFileDescriptor(fd);
        data.writeStringArray(args);
        try {
            transact(DUMP_TRANSACTION, data, reply, FLAG_ONEWAY);
        } finally {
            data.recycle();
            reply.recycle();
        }
    }

    public void shellCommand(FileDescriptor in, FileDescriptor out, FileDescriptor err,
            String[] args, ShellCallback callback,
            ResultReceiver resultReceiver) throws RemoteException {
        Parcel data = Parcel.obtain();
        Parcel reply = Parcel.obtain();
        data.writeFileDescriptor(in);
        data.writeFileDescriptor(out);
        data.writeFileDescriptor(err);
        data.writeStringArray(args);
        ShellCallback.writeToParcel(callback, data);
        resultReceiver.writeToParcel(data, 0);
        try {
            transact(SHELL_COMMAND_TRANSACTION, data, reply, 0);
            reply.readException();
        } finally {
            data.recycle();
            reply.recycle();
        }
    }

    private static final void sendDeathNotice(DeathRecipient recipient) {
        if (false) Log.v("JavaBinder", "sendDeathNotice to " + recipient);
        try {
            recipient.binderDied();
        }
        catch (RuntimeException exc) {
            Log.w("BinderNative", "Uncaught exception from death notification",
                    exc);
        }
    }

    
C++ pointer to BinderProxyNativeData. That consists of strong pointers to the
native IBinder object, and a DeathRecipientList.

/**
     * C++ pointer to BinderProxyNativeData. That consists of strong pointers to the
     * native IBinder object, and a DeathRecipientList.
     */
    private final long mNativeData;
}