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	/*
	* Copyright (c) 2011, 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
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package com.sun.management;

	import java.lang.management.ThreadInfo;
	import java.util.Map;

	/**
	* Platform-specific management interface for the thread system
	* of the Java virtual machine.
	* <p>
	* This platform extension is only available to a thread
	* implementation that supports this extension.
	*
	* @author Paul Hohensee
	* @since 6u25
	*/

	@jdk.Exported
	public interface ThreadMXBean extends java.lang.management.ThreadMXBean {
	/**
	* Returns the total CPU time for each thread whose ID is
	* in the input array {@code ids} in nanoseconds.
	* The returned values are of nanoseconds precision but
	* not necessarily nanoseconds accuracy.
	* <p>
	* This method is equivalent to calling the
	* {@link ThreadMXBean#getThreadCpuTime(long)}
	* method for each thread ID in the input array {@code ids} and setting the
	* returned value in the corresponding element of the returned array.
	*
	* @param ids an array of thread IDs.
	* @return an array of long values, each of which is the amount of CPU
	* time the thread whose ID is in the corresponding element of the input
	* array of IDs has used,
	* if the thread of a specified ID exists, the thread is alive,
	* and CPU time measurement is enabled;
	* {@code -1} otherwise.
	*
	* @throws NullPointerException if {@code ids} is {@code null}
	* @throws IllegalArgumentException if any element in the input array
	* {@code ids} is {@code <=} {@code 0}.
	* @throws UnsupportedOperationException if the Java
	* virtual machine implementation does not support CPU time
	* measurement.
	*
	* @see ThreadMXBean#getThreadCpuTime(long)
	* @see #getThreadUserTime
	* @see ThreadMXBean#isThreadCpuTimeSupported
	* @see ThreadMXBean#isThreadCpuTimeEnabled
	* @see ThreadMXBean#setThreadCpuTimeEnabled
	*/
	public long[] getThreadCpuTime(long[] ids);

	/**
	* Returns the CPU time that each thread whose ID is in the input array
	* {@code ids} has executed in user mode in nanoseconds.
	* The returned values are of nanoseconds precision but
	* not necessarily nanoseconds accuracy.
	* <p>
	* This method is equivalent to calling the
	* {@link ThreadMXBean#getThreadUserTime(long)}
	* method for each thread ID in the input array {@code ids} and setting the
	* returned value in the corresponding element of the returned array.
	*
	* @param ids an array of thread IDs.
	* @return an array of long values, each of which is the amount of user
	* mode CPU time the thread whose ID is in the corresponding element of
	* the input array of IDs has used,
	* if the thread of a specified ID exists, the thread is alive,
	* and CPU time measurement is enabled;
	* {@code -1} otherwise.
	*
	* @throws NullPointerException if {@code ids} is {@code null}
	* @throws IllegalArgumentException if any element in the input array
	* {@code ids} is {@code <=} {@code 0}.
	* @throws UnsupportedOperationException if the Java
	* virtual machine implementation does not support CPU time
	* measurement.
	*
	* @see ThreadMXBean#getThreadUserTime(long)
	* @see #getThreadCpuTime
	* @see ThreadMXBean#isThreadCpuTimeSupported
	* @see ThreadMXBean#isThreadCpuTimeEnabled
	* @see ThreadMXBean#setThreadCpuTimeEnabled
	*/
	public long[] getThreadUserTime(long[] ids);

	/**
	* Returns an approximation of the total amount of memory, in bytes,
	* allocated in heap memory for the current thread.
	* The returned value is an approximation because some Java virtual machine
	* implementations may use object allocation mechanisms that result in a
	* delay between the time an object is allocated and the time its size is
	* recorded.
	*
	* <p>
	* This is a convenience method for local management use and is
	* equivalent to calling:
	* <blockquote><pre>
	* {@link #getThreadAllocatedBytes getThreadAllocatedBytes}(Thread.currentThread().getId());
	* </pre></blockquote>
	*
	* @return an approximation of the total memory allocated, in bytes, in
	* heap memory for the current thread
	* if thread memory allocation measurement is enabled;
	* {@code -1} otherwise.
	*
	* @throws UnsupportedOperationException if the Java virtual
	* machine implementation does not support thread memory allocation
	* measurement.
	*
	* @see #isThreadAllocatedMemorySupported
	* @see #isThreadAllocatedMemoryEnabled
	* @see #setThreadAllocatedMemoryEnabled
	*
	* @since 8u282
	*/
	public default long getCurrentThreadAllocatedBytes() {
	return getThreadAllocatedBytes(Thread.currentThread().getId());
	}

	/**
	* Returns an approximation of the total amount of memory, in bytes,
	* allocated in heap memory for the thread with the specified ID.
	* The returned value is an approximation because some Java virtual machine
	* implementations may use object allocation mechanisms that result in a
	* delay between the time an object is allocated and the time its size is
	* recorded.
	* <p>
	* If the thread with the specified ID is not alive or does not exist,
	* this method returns {@code -1}. If thread memory allocation measurement
	* is disabled, this method returns {@code -1}.
	* A thread is alive if it has been started and has not yet died.
	* <p>
	* If thread memory allocation 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 thread memory allocation measurement starts.
	*
	* @param id the thread ID of a thread
	* @return an approximation of the total memory allocated, in bytes, in
	* heap memory for the thread with the specified ID
	* if the thread with the specified ID exists, the thread is alive,
	* and thread memory allocation measurement is enabled;
	* {@code -1} otherwise.
	*
	* @throws IllegalArgumentException if {@code id} {@code <=} {@code 0}.
	* @throws UnsupportedOperationException if the Java virtual
	* machine implementation does not support thread memory allocation
	* measurement.
	*
	* @see #isThreadAllocatedMemorySupported
	* @see #isThreadAllocatedMemoryEnabled
	* @see #setThreadAllocatedMemoryEnabled
	*/
	public long getThreadAllocatedBytes(long id);

	/**
	* Returns an approximation of the total amount of memory, in bytes,
	* allocated in heap memory for each thread whose ID is in the input
	* array {@code ids}.
	* The returned values are approximations because some Java virtual machine
	* implementations may use object allocation mechanisms that result in a
	* delay between the time an object is allocated and the time its size is
	* recorded.
	* <p>
	* This method is equivalent to calling the
	* {@link #getThreadAllocatedBytes(long)}
	* method for each thread ID in the input array {@code ids} and setting the
	* returned value in the corresponding element of the returned array.
	*
	* @param ids an array of thread IDs.
	* @return an array of long values, each of which is an approximation of
	* the total memory allocated, in bytes, in heap memory for the thread
	* whose ID is in the corresponding element of the input array of IDs.
	*
	* @throws NullPointerException if {@code ids} is {@code null}
	* @throws IllegalArgumentException if any element in the input array
	* {@code ids} is {@code <=} {@code 0}.
	* @throws UnsupportedOperationException if the Java virtual
	* machine implementation does not support thread memory allocation
	* measurement.
	*
	* @see #getThreadAllocatedBytes(long)
	* @see #isThreadAllocatedMemorySupported
	* @see #isThreadAllocatedMemoryEnabled
	* @see #setThreadAllocatedMemoryEnabled
	*/
	public long[] getThreadAllocatedBytes(long[] ids);

	/**
	* Tests if the Java virtual machine implementation supports thread memory
	* allocation measurement.
	*
	* @return
	* {@code true}
	* if the Java virtual machine implementation supports thread memory
	* allocation measurement;
	* {@code false} otherwise.
	*/
	public boolean isThreadAllocatedMemorySupported();

	/**
	* Tests if thread memory allocation measurement is enabled.
	*
	* @return {@code true} if thread memory allocation measurement is enabled;
	* {@code false} otherwise.
	*
	* @throws UnsupportedOperationException if the Java virtual
	* machine does not support thread memory allocation measurement.
	*
	* @see #isThreadAllocatedMemorySupported
	*/
	public boolean isThreadAllocatedMemoryEnabled();

	/**
	* Enables or disables thread memory allocation measurement. The default
	* is platform dependent.
	*
	* @param enable {@code true} to enable;
	* {@code false} to disable.
	*
	* @throws UnsupportedOperationException if the Java virtual
	* machine does not support thread memory allocation measurement.
	*
	* @throws SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("control").
	*
	* @see #isThreadAllocatedMemorySupported
	*/
	public void setThreadAllocatedMemoryEnabled(boolean enable);

	/**
	* Returns the thread info for each thread whose ID
	* is in the input array <tt>ids</tt>,
	* with stack trace of the specified maximum number of elements
	* and synchronization information.
	* If <tt>maxDepth == 0</tt>, no stack trace of the thread
	* will be dumped.
	*
	* <p>
	* This method obtains a snapshot of the thread information
	* for each thread including:
	* <ul>
	* <li>stack trace of the specified maximum number of elements,</li>
	* <li>the object monitors currently locked by the thread
	* if <tt>lockedMonitors</tt> is <tt>true</tt>, and</li>
	* <li>the <a href="{@docRoot}/../api/java/lang/management/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, maxDepth)}
	* </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.
	*
	* @implSpec The default implementation throws
	* <tt>UnsupportedOperationException</tt>.
	*
	* @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.
	* @param maxDepth indicates the maximum number of
	* {@link StackTraceElement} to be retrieved from the stack trace.
	*
	* @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 IllegalArgumentException if <tt>maxDepth</tt> is negative.
	* @throws java.lang.SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("monitor").
	* @throws java.lang.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 8u282
	*/

	public default ThreadInfo[] getThreadInfo(long[] ids, boolean lockedMonitors,
	boolean lockedSynchronizers, int maxDepth) {
	throw new UnsupportedOperationException();
	}

	/**
	* Returns the thread info for all live threads
	* with stack trace of the specified maximum number of elements
	* and synchronization information.
	* if <tt>maxDepth == 0</tt>, no stack trace of the thread
	* will be dumped.
	* 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, int)}
	* method.
	*
	* @implSpec The default implementation throws
	* <tt>UnsupportedOperationException</tt>.
	*
	* @param lockedMonitors if <tt>true</tt>, dump all locked monitors.
	* @param lockedSynchronizers if <tt>true</tt>, dump all locked
	* ownable synchronizers.
	* @param maxDepth indicates the maximum number of
	* {@link StackTraceElement} to be retrieved from the stack trace.
	*
	* @return an array of {@link ThreadInfo} for all live threads.
	*
	* @throws IllegalArgumentException if <tt>maxDepth</tt> is negative.
	* @throws java.lang.SecurityException if a security manager
	* exists and the caller does not have
	* ManagementPermission("monitor").
	* @throws java.lang.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 8u282
	*/
	public default ThreadInfo[] dumpAllThreads(boolean lockedMonitors,
	boolean lockedSynchronizers, int maxDepth) {
	throw new UnsupportedOperationException();
	}
	}

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