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	/*
	* Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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	*/

	package java.lang.management;

	import java.util.Map;

	/**
	* The management interface for the thread system of
	* the Java virtual machine.
	*
	* <p> A Java virtual machine has a single instance of the implementation
	* class of this interface. This instance implementing this interface is
	* an <a href="ManagementFactory.html#MXBean">MXBean</a>
	* that can be obtained by calling
	* the {@link ManagementFactory#getThreadMXBean} method or
	* from the {@link ManagementFactory#getPlatformMBeanServer
	* platform <tt>MBeanServer</tt>} method.
	*
	* <p>The <tt>ObjectName</tt> for uniquely identifying the MXBean for
	* the thread system within an MBeanServer is:
	* <blockquote>
	* {@link ManagementFactory#THREAD_MXBEAN_NAME
	* <tt>java.lang:type=Threading</tt>}
	* </blockquote>
	*
	* It can be obtained by calling the
	* {@link PlatformManagedObject#getObjectName} method.
	*
	* <h3>Thread ID</h3>
	* Thread ID is a positive long value returned by calling the
	* {@link java.lang.Thread#getId} method for a thread.
	* The thread ID is unique during its lifetime. When a thread
	* is terminated, this thread ID may be reused.
	*
	* <p> Some methods in this interface take a thread ID or an array
	* of thread IDs as the input parameter and return per-thread information.
	*
	* <h3>Thread CPU time</h3>
	* A Java virtual machine implementation may support measuring
	* the CPU time for the current thread, for any thread, or for no threads.
	*
	* <p>
	* The {@link #isThreadCpuTimeSupported} method can be used to determine
	* if a Java virtual machine supports measuring of the CPU time for any
	* thread. The {@link #isCurrentThreadCpuTimeSupported} method can
	* be used to determine if a Java virtual machine supports measuring of
	* the CPU time for the current thread.
	* A Java virtual machine implementation that supports CPU time measurement
	* for any thread will also support that for the current thread.
	*
	* <p> The CPU time provided by this interface has nanosecond precision
	* but not necessarily nanosecond accuracy.
	*
	* <p>
	* A Java virtual machine may disable CPU time measurement
	* by default.
	* The {@link #isThreadCpuTimeEnabled} and {@link #setThreadCpuTimeEnabled}
	* methods can be used to test if CPU time measurement is enabled
	* and to enable/disable this support respectively.
	* Enabling thread CPU measurement could be expensive in some
	* Java virtual machine implementations.
	*
	* <h3>Thread Contention Monitoring</h3>
	* Some Java virtual machines may support thread contention monitoring.
	* When thread contention monitoring is enabled, the accumulated elapsed
	* time that the thread has blocked for synchronization or waited for
	* notification will be collected and returned in the
	* <a href="ThreadInfo.html#SyncStats"><tt>ThreadInfo</tt></a> object.
	* <p>
	* The {@link #isThreadContentionMonitoringSupported} method can be used to
	* determine if a Java virtual machine supports thread contention monitoring.
	* The thread contention monitoring is disabled by default. The
	* {@link #setThreadContentionMonitoringEnabled} method can be used to enable
	* thread contention monitoring.
	*
	* <h3>Synchronization Information and Deadlock Detection</h3>
	* Some Java virtual machines may support monitoring of
	* {@linkplain #isObjectMonitorUsageSupported object monitor usage} and
	* {@linkplain #isSynchronizerUsageSupported ownable synchronizer usage}.
	* The {@link #getThreadInfo(long[], boolean, boolean)} and
	* {@link #dumpAllThreads} methods can be used to obtain the thread stack trace
	* and synchronization information including which
	* {@linkplain LockInfo <i>lock</i>} a thread is blocked to
	* acquire or waiting on and which locks the thread currently owns.
	* <p>
	* The <tt>ThreadMXBean</tt> interface provides the
	* {@link #findMonitorDeadlockedThreads} and
	* {@link #findDeadlockedThreads} methods to find deadlocks in
	* the running application.
	*
	* @see ManagementFactory#getPlatformMXBeans(Class)
	* @see <a href="../../../javax/management/package-summary.html">
	* JMX Specification.</a>
	* @see <a href="package-summary.html#examples">
	* Ways to Access MXBeans</a>
	*
	* @author Mandy Chung
	* @since 1.5
	*/

	public interface ThreadMXBean extends PlatformManagedObject {
	/**
	* Returns the current number of live threads including both
	* daemon and non-daemon threads.
	*
	* @return the current number of live threads.
	*/
	public int getThreadCount();

	/**
	* Returns the peak live thread count since the Java virtual machine
	* started or peak was reset.
	*
	* @return the peak live thread count.
	*/
	public int getPeakThreadCount();

	/**
	* Returns the total number of threads created and also started
	* since the Java virtual machine started.
	*
	* @return the total number of threads started.
	*/
	public long getTotalStartedThreadCount();

	/**
	* Returns the current number of live daemon threads.
	*
	* @return the current number of live daemon threads.
	*/
	public int getDaemonThreadCount();

	/**
	* Returns all live thread IDs.
	* Some threads included in the returned array
	* may have been terminated when this method returns.
	*
	* @return an array of <tt>long</tt>, each is a thread ID.
	*
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("monitor").
	*/
	public long[] getAllThreadIds();

	/**
	* Returns the thread info for a thread of the specified
	* <tt>id</tt> with no stack trace.
	* This method is equivalent to calling:
	* <blockquote>
	* {@link #getThreadInfo(long, int) getThreadInfo(id, 0);}
	* </blockquote>
	*
	* <p>
	* This method returns a <tt>ThreadInfo</tt> object representing
	* the thread information for the thread of the specified ID.
	* The stack trace, locked monitors, and locked synchronizers
	* in the returned <tt>ThreadInfo</tt> object will
	* be empty.
	*
	* If a thread of the given ID is not alive or does not exist,
	* this method will return <tt>null</tt>. A thread is alive if
	* it has been started and has not yet died.
	*
	* <p>
	* <b>MBeanServer access</b>:<br>
	* The mapped type of <tt>ThreadInfo</tt> is
	* <tt>CompositeData</tt> with attributes as specified in the
	* {@link ThreadInfo#from ThreadInfo.from} method.
	*
	* @param id the thread ID of the thread. Must be positive.
	*
	* @return a {@link ThreadInfo} object for the thread of the given ID
	* with no stack trace, no locked monitor and no synchronizer info;
	* <tt>null</tt> if the thread of the given ID is not alive or
	* it does not exist.
	*
	* @throws IllegalArgumentException if {@code id <= 0}.
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("monitor").
	*/
	public ThreadInfo getThreadInfo(long id);

	/**
	* Returns the thread info for each thread
	* whose ID is in the input array <tt>ids</tt> with no stack trace.
	* This method is equivalent to calling:
	* <blockquote><pre>
	* {@link #getThreadInfo(long[], int) getThreadInfo}(ids, 0);
	* </pre></blockquote>
	*
	* <p>
	* This method returns an array of the <tt>ThreadInfo</tt> objects.
	* The stack trace, locked monitors, and locked synchronizers
	* in each <tt>ThreadInfo</tt> object will be empty.
	*
	* If a thread of a given ID is not alive or does not exist,
	* the corresponding element in the returned array will
	* contain <tt>null</tt>. A thread is alive if
	* it has been started and has not yet died.
	*
	* <p>
	* <b>MBeanServer access</b>:<br>
	* The mapped type of <tt>ThreadInfo</tt> is
	* <tt>CompositeData</tt> with attributes as specified in the
	* {@link ThreadInfo#from ThreadInfo.from} method.
	*
	* @param ids an array of thread IDs.
	* @return an array of the {@link ThreadInfo} objects, each containing
	* information about a thread whose ID is in the corresponding
	* element of the input array of IDs
	* with no stack trace, no locked monitor and no synchronizer info.
	*
	* @throws IllegalArgumentException if any element in the input array
	* <tt>ids</tt> is {@code <= 0}.
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("monitor").
	*/
	public ThreadInfo[] getThreadInfo(long[] ids);

	/**
	* Returns a thread info for a thread of the specified <tt>id</tt>,
	* with stack trace of a specified number of stack trace elements.
	* The <tt>maxDepth</tt> parameter indicates the maximum number of
	* {@link StackTraceElement} to be retrieved from the stack trace.
	* If <tt>maxDepth == Integer.MAX_VALUE</tt>, the entire stack trace of
	* the thread will be dumped.
	* If <tt>maxDepth == 0</tt>, no stack trace of the thread
	* will be dumped.
	* This method does not obtain the locked monitors and locked
	* synchronizers of the thread.
	* <p>
	* When the Java virtual machine has no stack trace information
	* about a thread or <tt>maxDepth == 0</tt>,
	* the stack trace in the
	* <tt>ThreadInfo</tt> object will be an empty array of
	* <tt>StackTraceElement</tt>.
	*
	* <p>
	* If a thread of the given ID is not alive or does not exist,
	* this method will return <tt>null</tt>. A thread is alive if
	* it has been started and has not yet died.
	*
	* <p>
	* <b>MBeanServer access</b>:<br>
	* The mapped type of <tt>ThreadInfo</tt> is
	* <tt>CompositeData</tt> with attributes as specified in the
	* {@link ThreadInfo#from ThreadInfo.from} method.
	*
	* @param id the thread ID of the thread. Must be positive.
	* @param maxDepth the maximum number of entries in the stack trace
	* to be dumped. <tt>Integer.MAX_VALUE</tt> could be used to request
	* the entire stack to be dumped.
	*
	* @return a {@link ThreadInfo} of the thread of the given ID
	* with no locked monitor and synchronizer info.
	* <tt>null</tt> if the thread of the given ID is not alive or
	* it does not exist.
	*
	* @throws IllegalArgumentException if {@code id <= 0}.
	* @throws IllegalArgumentException if <tt>maxDepth is negative</tt>.
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("monitor").
	*
	*/
	public ThreadInfo getThreadInfo(long id, int maxDepth);

	/**
	* Returns the thread info for each thread
	* whose ID is in the input array <tt>ids</tt>,
	* with stack trace of a specified number of stack trace elements.
	* The <tt>maxDepth</tt> parameter indicates the maximum number of
	* {@link StackTraceElement} to be retrieved from the stack trace.
	* If <tt>maxDepth == Integer.MAX_VALUE</tt>, the entire stack trace of
	* the thread will be dumped.
	* If <tt>maxDepth == 0</tt>, no stack trace of the thread
	* will be dumped.
	* This method does not obtain the locked monitors and locked
	* synchronizers of the threads.
	* <p>
	* When the Java virtual machine has no stack trace information
	* about a thread or <tt>maxDepth == 0</tt>,
	* the stack trace in the
	* <tt>ThreadInfo</tt> object will be an empty array of
	* <tt>StackTraceElement</tt>.
	* <p>
	* This method returns an array of the <tt>ThreadInfo</tt> objects,
	* each is the thread information about the thread with the same index
	* as in the <tt>ids</tt> array.
	* If a thread of the given ID is not alive or does not exist,
	* <tt>null</tt> will be set in the corresponding element
	* in the returned array. A thread is alive if
	* it has been started and has not yet died.
	*
	* <p>
	* <b>MBeanServer access</b>:<br>
	* The mapped type of <tt>ThreadInfo</tt> is
	* <tt>CompositeData</tt> with attributes as specified in the
	* {@link ThreadInfo#from ThreadInfo.from} method.
	*
	* @param ids an array of thread IDs
	* @param maxDepth the maximum number of entries in the stack trace
	* to be dumped. <tt>Integer.MAX_VALUE</tt> could be used to request
	* the entire stack to be dumped.
	*
	* @return an array of the {@link ThreadInfo} objects, each containing
	* information about a thread whose ID is in the corresponding
	* element of the input array of IDs with no locked monitor and
	* synchronizer info.
	*
	* @throws IllegalArgumentException if <tt>maxDepth is negative</tt>.
	* @throws IllegalArgumentException if any element in the input array
	* <tt>ids</tt> is {@code <= 0}.
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("monitor").
	*
	*/
	public ThreadInfo[] getThreadInfo(long[] ids, int maxDepth);

	/**
	* Tests if the Java virtual machine supports thread contention monitoring.
	*
	* @return
	* <tt>true</tt>
	* if the Java virtual machine supports thread contention monitoring;
	* <tt>false</tt> otherwise.
	*/
	public boolean isThreadContentionMonitoringSupported();

	/**
	* Tests if thread contention monitoring is enabled.
	*
	* @return <tt>true</tt> if thread contention monitoring is enabled;
	* <tt>false</tt> otherwise.
	*
	* @throws UnsupportedOperationException if the Java virtual
	* machine does not support thread contention monitoring.
	*
	* @see #isThreadContentionMonitoringSupported
	*/
	public boolean isThreadContentionMonitoringEnabled();

	/**
	* Enables or disables thread contention monitoring.
	* Thread contention monitoring is disabled by default.
	*
	* @param enable <tt>true</tt> to enable;
	* <tt>false</tt> to disable.
	*
	* @throws UnsupportedOperationException if the Java
	* virtual machine does not support thread contention monitoring.
	*
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("control").
	*
	* @see #isThreadContentionMonitoringSupported
	*/
	public void setThreadContentionMonitoringEnabled(boolean enable);

	/**
	* Returns the total CPU time for the current thread in nanoseconds.
	* The returned value is of nanoseconds precision but
	* not necessarily nanoseconds accuracy.
	* If the implementation distinguishes between user mode time and system
	* mode time, the returned CPU time is the amount of time that
	* the current thread has executed in user mode or system mode.
	*
	* <p>
	* This is a convenience method for local management use and is
	* equivalent to calling:
	* <blockquote><pre>
	* {@link #getThreadCpuTime getThreadCpuTime}(Thread.currentThread().getId());
	* </pre></blockquote>
	*
	* @return the total CPU time for the current thread if CPU time
	* measurement is enabled; <tt>-1</tt> otherwise.
	*
	* @throws UnsupportedOperationException if the Java
	* virtual machine does not support CPU time measurement for
	* the current thread.
	*
	* @see #getCurrentThreadUserTime
	* @see #isCurrentThreadCpuTimeSupported
	* @see #isThreadCpuTimeEnabled
	* @see #setThreadCpuTimeEnabled
	*/
	public long getCurrentThreadCpuTime();

	/**
	* Returns the CPU time that the current thread has executed
	* in user mode in nanoseconds.
	* The returned value is of nanoseconds precision but
	* not necessarily nanoseconds accuracy.
	*
	* <p>
	* This is a convenience method for local management use and is
	* equivalent to calling:
	* <blockquote><pre>
	* {@link #getThreadUserTime getThreadUserTime}(Thread.currentThread().getId());
	* </pre></blockquote>
	*
	* @return the user-level CPU time for the current thread if CPU time
	* measurement is enabled; <tt>-1</tt> otherwise.
	*
	* @throws UnsupportedOperationException if the Java
	* virtual machine does not support CPU time measurement for
	* the current thread.
	*
	* @see #getCurrentThreadCpuTime
	* @see #isCurrentThreadCpuTimeSupported
	* @see #isThreadCpuTimeEnabled
	* @see #setThreadCpuTimeEnabled
	*/
	public long getCurrentThreadUserTime();

	/**
	* Returns the total CPU time for a thread of the specified ID in nanoseconds.
	* The returned value is of nanoseconds precision but
	* not necessarily nanoseconds accuracy.
	* If the implementation distinguishes between user mode time and system
	* mode time, the returned CPU time is the amount of time that
	* the thread has executed in user mode or system mode.
	*
	* <p>
	* If the thread of the specified ID is not alive or does not exist,
	* this method returns <tt>-1</tt>. If CPU time measurement
	* is disabled, this method returns <tt>-1</tt>.
	* A thread is alive if it has been started and has not yet died.
	* <p>
	* If CPU time measurement is enabled after the thread has started,
	* the Java virtual machine implementation may choose any time up to
	* and including the time that the capability is enabled as the point
	* where CPU time measurement starts.
	*
	* @param id the thread ID of a thread
	* @return the total CPU time for a thread of the specified ID
	* if the thread of the specified ID exists, the thread is alive,
	* and CPU time measurement is enabled;
	* <tt>-1</tt> otherwise.
	*
	* @throws IllegalArgumentException if {@code id <= 0}.
	* @throws UnsupportedOperationException if the Java
	* virtual machine does not support CPU time measurement for
	* other threads.
	*
	* @see #getThreadUserTime
	* @see #isThreadCpuTimeSupported
	* @see #isThreadCpuTimeEnabled
	* @see #setThreadCpuTimeEnabled
	*/
	public long getThreadCpuTime(long id);

	/**
	* Returns the CPU time that a thread of the specified ID
	* has executed in user mode in nanoseconds.
	* The returned value is of nanoseconds precision but
	* not necessarily nanoseconds accuracy.
	*
	* <p>
	* If the thread of the specified ID is not alive or does not exist,
	* this method returns <tt>-1</tt>. If CPU time measurement
	* is disabled, this method returns <tt>-1</tt>.
	* A thread is alive if it has been started and has not yet died.
	* <p>
	* If CPU time measurement is enabled after the thread has started,
	* the Java virtual machine implementation may choose any time up to
	* and including the time that the capability is enabled as the point
	* where CPU time measurement starts.
	*
	* @param id the thread ID of a thread
	* @return the user-level CPU time for a thread of the specified ID
	* if the thread of the specified ID exists, the thread is alive,
	* and CPU time measurement is enabled;
	* <tt>-1</tt> otherwise.
	*
	* @throws IllegalArgumentException if {@code id <= 0}.
	* @throws UnsupportedOperationException if the Java
	* virtual machine does not support CPU time measurement for
	* other threads.
	*
	* @see #getThreadCpuTime
	* @see #isThreadCpuTimeSupported
	* @see #isThreadCpuTimeEnabled
	* @see #setThreadCpuTimeEnabled
	*/
	public long getThreadUserTime(long id);

	/**
	* Tests if the Java virtual machine implementation supports CPU time
	* measurement for any thread.
	* A Java virtual machine implementation that supports CPU time
	* measurement for any thread will also support CPU time
	* measurement for the current thread.
	*
	* @return
	* <tt>true</tt>
	* if the Java virtual machine supports CPU time
	* measurement for any thread;
	* <tt>false</tt> otherwise.
	*/
	public boolean isThreadCpuTimeSupported();

	/**
	* Tests if the Java virtual machine supports CPU time
	* measurement for the current thread.
	* This method returns <tt>true</tt> if {@link #isThreadCpuTimeSupported}
	* returns <tt>true</tt>.
	*
	* @return
	* <tt>true</tt>
	* if the Java virtual machine supports CPU time
	* measurement for current thread;
	* <tt>false</tt> otherwise.
	*/
	public boolean isCurrentThreadCpuTimeSupported();

	/**
	* Tests if thread CPU time measurement is enabled.
	*
	* @return <tt>true</tt> if thread CPU time measurement is enabled;
	* <tt>false</tt> otherwise.
	*
	* @throws UnsupportedOperationException if the Java virtual
	* machine does not support CPU time measurement for other threads
	* nor for the current thread.
	*
	* @see #isThreadCpuTimeSupported
	* @see #isCurrentThreadCpuTimeSupported
	*/
	public boolean isThreadCpuTimeEnabled();

	/**
	* Enables or disables thread CPU time measurement. The default
	* is platform dependent.
	*
	* @param enable <tt>true</tt> to enable;
	* <tt>false</tt> to disable.
	*
	* @throws UnsupportedOperationException if the Java
	* virtual machine does not support CPU time measurement for
	* any threads nor for the current thread.
	*
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("control").
	*
	* @see #isThreadCpuTimeSupported
	* @see #isCurrentThreadCpuTimeSupported
	*/
	public void setThreadCpuTimeEnabled(boolean enable);

	/**
	* Finds cycles of threads that are in deadlock waiting to acquire
	* object monitors. That is, threads that are blocked waiting to enter a
	* synchronization block or waiting to reenter a synchronization block
	* after an {@link Object#wait Object.wait} call,
	* where each thread owns one monitor while
	* trying to obtain another monitor already held by another thread
	* in a cycle.
	* <p>
	* More formally, a thread is <em>monitor deadlocked</em> if it is
	* part of a cycle in the relation "is waiting for an object monitor
	* owned by". In the simplest case, thread A is blocked waiting
	* for a monitor owned by thread B, and thread B is blocked waiting
	* for a monitor owned by thread A.
	* <p>
	* This method is designed for troubleshooting use, but not for
	* synchronization control. It might be an expensive operation.
	* <p>
	* This method finds deadlocks involving only object monitors.
	* To find deadlocks involving both object monitors and
	* <a href="LockInfo.html#OwnableSynchronizer">ownable synchronizers</a>,
	* the {@link #findDeadlockedThreads findDeadlockedThreads} method
	* should be used.
	*
	* @return an array of IDs of the threads that are monitor
	* deadlocked, if any; <tt>null</tt> otherwise.
	*
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("monitor").
	*
	* @see #findDeadlockedThreads
	*/
	public long[] findMonitorDeadlockedThreads();

	/**
	* Resets the peak thread count to the current number of
	* live threads.
	*
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("control").
	*
	* @see #getPeakThreadCount
	* @see #getThreadCount
	*/
	public void resetPeakThreadCount();

	/**
	* Finds cycles of threads that are in deadlock waiting to acquire
	* object monitors or
	* <a href="LockInfo.html#OwnableSynchronizer">ownable synchronizers</a>.
	*
	* Threads are <em>deadlocked</em> in a cycle waiting for a lock of
	* these two types if each thread owns one lock while
	* trying to acquire another lock already held
	* by another thread in the cycle.
	* <p>
	* This method is designed for troubleshooting use, but not for
	* synchronization control. It might be an expensive operation.
	*
	* @return an array of IDs of the threads that are
	* deadlocked waiting for object monitors or ownable synchronizers, if any;
	* <tt>null</tt> otherwise.
	*
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("monitor").
	* @throws UnsupportedOperationException if the Java virtual
	* machine does not support monitoring of ownable synchronizer usage.
	*
	* @see #isSynchronizerUsageSupported
	* @see #findMonitorDeadlockedThreads
	* @since 1.6
	*/
	public long[] findDeadlockedThreads();

	/**
	* Tests if the Java virtual machine supports monitoring of
	* object monitor usage.
	*
	* @return
	* <tt>true</tt>
	* if the Java virtual machine supports monitoring of
	* object monitor usage;
	* <tt>false</tt> otherwise.
	*
	* @see #dumpAllThreads
	* @since 1.6
	*/
	public boolean isObjectMonitorUsageSupported();

	/**
	* Tests if the Java virtual machine supports monitoring of
	* <a href="LockInfo.html#OwnableSynchronizer">
	* ownable synchronizer</a> usage.
	*
	* @return
	* <tt>true</tt>
	* if the Java virtual machine supports monitoring of ownable
	* synchronizer usage;
	* <tt>false</tt> otherwise.
	*
	* @see #dumpAllThreads
	* @since 1.6
	*/
	public boolean isSynchronizerUsageSupported();

	/**
	* Returns the thread info for each thread
	* whose ID is in the input array <tt>ids</tt>, with stack trace
	* and synchronization information.
	*
	* <p>
	* This method obtains a snapshot of the thread information
	* for each thread including:
	* <ul>
	* <li>the entire stack trace,</li>
	* <li>the object monitors currently locked by the thread
	* if <tt>lockedMonitors</tt> is <tt>true</tt>, and</li>
	* <li>the <a href="LockInfo.html#OwnableSynchronizer">
	* ownable synchronizers</a> currently locked by the thread
	* if <tt>lockedSynchronizers</tt> is <tt>true</tt>.</li>
	* </ul>
	* <p>
	* This method returns an array of the <tt>ThreadInfo</tt> objects,
	* each is the thread information about the thread with the same index
	* as in the <tt>ids</tt> array.
	* If a thread of the given ID is not alive or does not exist,
	* <tt>null</tt> will be set in the corresponding element
	* in the returned array. A thread is alive if
	* it has been started and has not yet died.
	* <p>
	* If a thread does not lock any object monitor or <tt>lockedMonitors</tt>
	* is <tt>false</tt>, the returned <tt>ThreadInfo</tt> object will have an
	* empty <tt>MonitorInfo</tt> array. Similarly, if a thread does not
	* lock any synchronizer or <tt>lockedSynchronizers</tt> is <tt>false</tt>,
	* the returned <tt>ThreadInfo</tt> object
	* will have an empty <tt>LockInfo</tt> array.
	*
	* <p>
	* When both <tt>lockedMonitors</tt> and <tt>lockedSynchronizers</tt>
	* parameters are <tt>false</tt>, it is equivalent to calling:
	* <blockquote><pre>
	* {@link #getThreadInfo(long[], int) getThreadInfo(ids, Integer.MAX_VALUE)}
	* </pre></blockquote>
	*
	* <p>
	* This method is designed for troubleshooting use, but not for
	* synchronization control. It might be an expensive operation.
	*
	* <p>
	* <b>MBeanServer access</b>:<br>
	* The mapped type of <tt>ThreadInfo</tt> is
	* <tt>CompositeData</tt> with attributes as specified in the
	* {@link ThreadInfo#from ThreadInfo.from} method.
	*
	* @param ids an array of thread IDs.
	* @param lockedMonitors if <tt>true</tt>, retrieves all locked monitors.
	* @param lockedSynchronizers if <tt>true</tt>, retrieves all locked
	* ownable synchronizers.
	*
	* @return an array of the {@link ThreadInfo} objects, each containing
	* information about a thread whose ID is in the corresponding
	* element of the input array of IDs.
	*
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("monitor").
	* @throws UnsupportedOperationException
	* <ul>
	* <li>if <tt>lockedMonitors</tt> is <tt>true</tt> but
	* the Java virtual machine does not support monitoring
	* of {@linkplain #isObjectMonitorUsageSupported
	* object monitor usage}; or</li>
	* <li>if <tt>lockedSynchronizers</tt> is <tt>true</tt> but
	* the Java virtual machine does not support monitoring
	* of {@linkplain #isSynchronizerUsageSupported
	* ownable synchronizer usage}.</li>
	* </ul>
	*
	* @see #isObjectMonitorUsageSupported
	* @see #isSynchronizerUsageSupported
	*
	* @since 1.6
	*/
	public ThreadInfo[] getThreadInfo(long[] ids, boolean lockedMonitors, boolean lockedSynchronizers);

	/**
	* Returns the thread info for all live threads with stack trace
	* and synchronization information.
	* Some threads included in the returned array
	* may have been terminated when this method returns.
	*
	* <p>
	* This method returns an array of {@link ThreadInfo} objects
	* as specified in the {@link #getThreadInfo(long[], boolean, boolean)}
	* method.
	*
	* @param lockedMonitors if <tt>true</tt>, dump all locked monitors.
	* @param lockedSynchronizers if <tt>true</tt>, dump all locked
	* ownable synchronizers.
	*
	* @return an array of {@link ThreadInfo} for all live threads.
	*
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("monitor").
	* @throws UnsupportedOperationException
	* <ul>
	* <li>if <tt>lockedMonitors</tt> is <tt>true</tt> but
	* the Java virtual machine does not support monitoring
	* of {@linkplain #isObjectMonitorUsageSupported
	* object monitor usage}; or</li>
	* <li>if <tt>lockedSynchronizers</tt> is <tt>true</tt> but
	* the Java virtual machine does not support monitoring
	* of {@linkplain #isSynchronizerUsageSupported
	* ownable synchronizer usage}.</li>
	* </ul>
	*
	* @see #isObjectMonitorUsageSupported
	* @see #isSynchronizerUsageSupported
	*
	* @since 1.6
	*/
	public ThreadInfo[] dumpAllThreads(boolean lockedMonitors, boolean lockedSynchronizers);
	}

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