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package sun.management;

import java.lang.management.ManagementFactory;
import java.lang.management.ThreadInfo;
import java.lang.management.ThreadMXBean;
import javax.management.ObjectName;

Implementation for java.lang.management.ThreadMXBean as well as providing the supporting method for com.sun.management.ThreadMXBean. The supporting method for com.sun.management.ThreadMXBean can be moved to jdk.management in the future.
/** * Implementation for java.lang.management.ThreadMXBean as well as providing the * supporting method for com.sun.management.ThreadMXBean. * The supporting method for com.sun.management.ThreadMXBean can be moved to * jdk.management in the future. */
public class ThreadImpl implements ThreadMXBean { private final VMManagement jvm; // default for thread contention monitoring is disabled. private boolean contentionMonitoringEnabled = false; private boolean cpuTimeEnabled; private boolean allocatedMemoryEnabled;
Constructor of ThreadImpl class.
/** * Constructor of ThreadImpl class. */
protected ThreadImpl(VMManagement vm) { this.jvm = vm; this.cpuTimeEnabled = jvm.isThreadCpuTimeEnabled(); this.allocatedMemoryEnabled = jvm.isThreadAllocatedMemoryEnabled(); } @Override public int getThreadCount() { return jvm.getLiveThreadCount(); } @Override public int getPeakThreadCount() { return jvm.getPeakThreadCount(); } @Override public long getTotalStartedThreadCount() { return jvm.getTotalThreadCount(); } @Override public int getDaemonThreadCount() { return jvm.getDaemonThreadCount(); } @Override public boolean isThreadContentionMonitoringSupported() { return jvm.isThreadContentionMonitoringSupported(); } @Override public synchronized boolean isThreadContentionMonitoringEnabled() { if (!isThreadContentionMonitoringSupported()) { throw new UnsupportedOperationException( "Thread contention monitoring is not supported."); } return contentionMonitoringEnabled; } @Override public boolean isThreadCpuTimeSupported() { return jvm.isOtherThreadCpuTimeSupported(); } @Override public boolean isCurrentThreadCpuTimeSupported() { return jvm.isCurrentThreadCpuTimeSupported(); } protected boolean isThreadAllocatedMemorySupported() { return jvm.isThreadAllocatedMemorySupported(); } @Override public boolean isThreadCpuTimeEnabled() { if (!isThreadCpuTimeSupported() && !isCurrentThreadCpuTimeSupported()) { throw new UnsupportedOperationException( "Thread CPU time measurement is not supported"); } return cpuTimeEnabled; } protected boolean isThreadAllocatedMemoryEnabled() { if (!isThreadAllocatedMemorySupported()) { throw new UnsupportedOperationException( "Thread allocated memory measurement is not supported"); } return allocatedMemoryEnabled; } @Override public long[] getAllThreadIds() { Util.checkMonitorAccess(); Thread[] threads = getThreads(); int length = threads.length; long[] ids = new long[length]; for (int i = 0; i < length; i++) { Thread t = threads[i]; ids[i] = t.getId(); } return ids; } @Override public ThreadInfo getThreadInfo(long id) { long[] ids = new long[1]; ids[0] = id; final ThreadInfo[] infos = getThreadInfo(ids, 0); return infos[0]; } @Override public ThreadInfo getThreadInfo(long id, int maxDepth) { long[] ids = new long[1]; ids[0] = id; final ThreadInfo[] infos = getThreadInfo(ids, maxDepth); return infos[0]; } @Override public ThreadInfo[] getThreadInfo(long[] ids) { return getThreadInfo(ids, 0); } private void verifyThreadIds(long[] ids) { if (ids == null) { throw new NullPointerException("Null ids parameter."); } for (int i = 0; i < ids.length; i++) { if (ids[i] <= 0) { throw new IllegalArgumentException( "Invalid thread ID parameter: " + ids[i]); } } } @Override public ThreadInfo[] getThreadInfo(long[] ids, int maxDepth) { verifyThreadIds(ids); if (maxDepth < 0) { throw new IllegalArgumentException( "Invalid maxDepth parameter: " + maxDepth); } // ids has been verified to be non-null // an empty array of ids should return an empty array of ThreadInfos if (ids.length == 0) return new ThreadInfo[0]; Util.checkMonitorAccess(); ThreadInfo[] infos = new ThreadInfo[ids.length]; // nulls if (maxDepth == Integer.MAX_VALUE) { getThreadInfo1(ids, -1, infos); } else { getThreadInfo1(ids, maxDepth, infos); } return infos; } @Override public void setThreadContentionMonitoringEnabled(boolean enable) { if (!isThreadContentionMonitoringSupported()) { throw new UnsupportedOperationException( "Thread contention monitoring is not supported"); } Util.checkControlAccess(); synchronized (this) { if (contentionMonitoringEnabled != enable) { if (enable) { // if reeabled, reset contention time statistics // for all threads resetContentionTimes0(0); } // update the VM of the state change setThreadContentionMonitoringEnabled0(enable); contentionMonitoringEnabled = enable; } } } private boolean verifyCurrentThreadCpuTime() { // check if Thread CPU time measurement is supported. if (!isCurrentThreadCpuTimeSupported()) { throw new UnsupportedOperationException( "Current thread CPU time measurement is not supported."); } return isThreadCpuTimeEnabled(); } @Override public long getCurrentThreadCpuTime() { if (verifyCurrentThreadCpuTime()) { return getThreadTotalCpuTime0(0); } return -1; } @Override public long getThreadCpuTime(long id) { long[] ids = new long[1]; ids[0] = id; final long[] times = getThreadCpuTime(ids); return times[0]; } private boolean verifyThreadCpuTime(long[] ids) { verifyThreadIds(ids); // check if Thread CPU time measurement is supported. if (!isThreadCpuTimeSupported() && !isCurrentThreadCpuTimeSupported()) { throw new UnsupportedOperationException( "Thread CPU time measurement is not supported."); } if (!isThreadCpuTimeSupported()) { // support current thread only for (int i = 0; i < ids.length; i++) { if (ids[i] != Thread.currentThread().getId()) { throw new UnsupportedOperationException( "Thread CPU time measurement is only supported" + " for the current thread."); } } } return isThreadCpuTimeEnabled(); } protected long[] getThreadCpuTime(long[] ids) { boolean verified = verifyThreadCpuTime(ids); int length = ids.length; long[] times = new long[length]; java.util.Arrays.fill(times, -1); if (verified) { if (length == 1) { long id = ids[0]; if (id == Thread.currentThread().getId()) { id = 0; } times[0] = getThreadTotalCpuTime0(id); } else { getThreadTotalCpuTime1(ids, times); } } return times; } @Override public long getCurrentThreadUserTime() { if (verifyCurrentThreadCpuTime()) { return getThreadUserCpuTime0(0); } return -1; } @Override public long getThreadUserTime(long id) { long[] ids = new long[1]; ids[0] = id; final long[] times = getThreadUserTime(ids); return times[0]; } protected long[] getThreadUserTime(long[] ids) { boolean verified = verifyThreadCpuTime(ids); int length = ids.length; long[] times = new long[length]; java.util.Arrays.fill(times, -1); if (verified) { if (length == 1) { long id = ids[0]; if (id == Thread.currentThread().getId()) { id = 0; } times[0] = getThreadUserCpuTime0(id); } else { getThreadUserCpuTime1(ids, times); } } return times; } @Override public void setThreadCpuTimeEnabled(boolean enable) { if (!isThreadCpuTimeSupported() && !isCurrentThreadCpuTimeSupported()) { throw new UnsupportedOperationException( "Thread CPU time measurement is not supported"); } Util.checkControlAccess(); synchronized (this) { if (cpuTimeEnabled != enable) { // notify VM of the state change setThreadCpuTimeEnabled0(enable); cpuTimeEnabled = enable; } } } protected long getThreadAllocatedBytes(long id) { long[] ids = new long[1]; ids[0] = id; final long[] sizes = getThreadAllocatedBytes(ids); return sizes[0]; } private boolean verifyThreadAllocatedMemory(long[] ids) { verifyThreadIds(ids); // check if Thread allocated memory measurement is supported. if (!isThreadAllocatedMemorySupported()) { throw new UnsupportedOperationException( "Thread allocated memory measurement is not supported."); } return isThreadAllocatedMemoryEnabled(); } protected long[] getThreadAllocatedBytes(long[] ids) { boolean verified = verifyThreadAllocatedMemory(ids); long[] sizes = new long[ids.length]; java.util.Arrays.fill(sizes, -1); if (verified) { getThreadAllocatedMemory1(ids, sizes); } return sizes; } protected void setThreadAllocatedMemoryEnabled(boolean enable) { if (!isThreadAllocatedMemorySupported()) { throw new UnsupportedOperationException( "Thread allocated memory measurement is not supported."); } Util.checkControlAccess(); synchronized (this) { if (allocatedMemoryEnabled != enable) { // notify VM of the state change setThreadAllocatedMemoryEnabled0(enable); allocatedMemoryEnabled = enable; } } } @Override public long[] findMonitorDeadlockedThreads() { Util.checkMonitorAccess(); Thread[] threads = findMonitorDeadlockedThreads0(); if (threads == null) { return null; } long[] ids = new long[threads.length]; for (int i = 0; i < threads.length; i++) { Thread t = threads[i]; ids[i] = t.getId(); } return ids; } @Override public long[] findDeadlockedThreads() { if (!isSynchronizerUsageSupported()) { throw new UnsupportedOperationException( "Monitoring of Synchronizer Usage is not supported."); } Util.checkMonitorAccess(); Thread[] threads = findDeadlockedThreads0(); if (threads == null) { return null; } long[] ids = new long[threads.length]; for (int i = 0; i < threads.length; i++) { Thread t = threads[i]; ids[i] = t.getId(); } return ids; } @Override public void resetPeakThreadCount() { Util.checkControlAccess(); resetPeakThreadCount0(); } @Override public boolean isObjectMonitorUsageSupported() { return jvm.isObjectMonitorUsageSupported(); } @Override public boolean isSynchronizerUsageSupported() { return jvm.isSynchronizerUsageSupported(); } private void verifyDumpThreads(boolean lockedMonitors, boolean lockedSynchronizers) { if (lockedMonitors && !isObjectMonitorUsageSupported()) { throw new UnsupportedOperationException( "Monitoring of Object Monitor Usage is not supported."); } if (lockedSynchronizers && !isSynchronizerUsageSupported()) { throw new UnsupportedOperationException( "Monitoring of Synchronizer Usage is not supported."); } Util.checkMonitorAccess(); } @Override public ThreadInfo[] getThreadInfo(long[] ids, boolean lockedMonitors, boolean lockedSynchronizers) { verifyThreadIds(ids); // ids has been verified to be non-null // an empty array of ids should return an empty array of ThreadInfos if (ids.length == 0) return new ThreadInfo[0]; verifyDumpThreads(lockedMonitors, lockedSynchronizers); return dumpThreads0(ids, lockedMonitors, lockedSynchronizers); } @Override public ThreadInfo[] dumpAllThreads(boolean lockedMonitors, boolean lockedSynchronizers) { verifyDumpThreads(lockedMonitors, lockedSynchronizers); return dumpThreads0(null, lockedMonitors, lockedSynchronizers); } // VM support where maxDepth == -1 to request entire stack dump private static native Thread[] getThreads(); private static native void getThreadInfo1(long[] ids, int maxDepth, ThreadInfo[] result); private static native long getThreadTotalCpuTime0(long id); private static native void getThreadTotalCpuTime1(long[] ids, long[] result); private static native long getThreadUserCpuTime0(long id); private static native void getThreadUserCpuTime1(long[] ids, long[] result); private static native void getThreadAllocatedMemory1(long[] ids, long[] result); private static native void setThreadCpuTimeEnabled0(boolean enable); private static native void setThreadAllocatedMemoryEnabled0(boolean enable); private static native void setThreadContentionMonitoringEnabled0(boolean enable); private static native Thread[] findMonitorDeadlockedThreads0(); private static native Thread[] findDeadlockedThreads0(); private static native void resetPeakThreadCount0(); private static native ThreadInfo[] dumpThreads0(long[] ids, boolean lockedMonitors, boolean lockedSynchronizers); // tid == 0 to reset contention times for all threads private static native void resetContentionTimes0(long tid); @Override public ObjectName getObjectName() { return Util.newObjectName(ManagementFactory.THREAD_MXBEAN_NAME); } }