/*

 * Copyright (c) 2003, 2011, 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 sun.management;

import java.lang.management.ManagementFactory;

import java.lang.management.ThreadInfo;

import javax.management.ObjectName;

/**

 * Implementation class for the thread subsystem.

 * Standard and committed hotspot-specific metrics if any.

 *

 * ManagementFactory.getThreadMXBean() returns an instance

 * of this class.

 */

class ThreadImpl implements com.sun.management.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.

     */

    ThreadImpl(VMManagement vm) {

        this.jvm = vm;

        this.cpuTimeEnabled = jvm.isThreadCpuTimeEnabled();

        this.allocatedMemoryEnabled = jvm.isThreadAllocatedMemoryEnabled();

    }

    public int getThreadCount() {

        return jvm.getLiveThreadCount();

    }

    public int getPeakThreadCount() {

        return jvm.getPeakThreadCount();

    }

    public long getTotalStartedThreadCount() {

        return jvm.getTotalThreadCount();

    }

    public int getDaemonThreadCount() {

        return jvm.getDaemonThreadCount();

    }

    public boolean isThreadContentionMonitoringSupported() {

        return jvm.isThreadContentionMonitoringSupported();

    }

    public synchronized boolean isThreadContentionMonitoringEnabled() {

       if (!isThreadContentionMonitoringSupported()) {

            throw new UnsupportedOperationException(

                "Thread contention monitoring is not supported.");

        }

        return contentionMonitoringEnabled;

    }

    public boolean isThreadCpuTimeSupported() {

        return jvm.isOtherThreadCpuTimeSupported();

    }

    public boolean isCurrentThreadCpuTimeSupported() {

        return jvm.isCurrentThreadCpuTimeSupported();

    }

    public boolean isThreadAllocatedMemorySupported() {

        return jvm.isThreadAllocatedMemorySupported();

    }

    public boolean isThreadCpuTimeEnabled() {

        if (!isThreadCpuTimeSupported() &&

            !isCurrentThreadCpuTimeSupported()) {

            throw new UnsupportedOperationException(

                "Thread CPU time measurement is not supported");

        }

        return cpuTimeEnabled;

    }

    public boolean isThreadAllocatedMemoryEnabled() {

        if (!isThreadAllocatedMemorySupported()) {

            throw new UnsupportedOperationException(

                "Thread allocated memory measurement is not supported");

        }

        return allocatedMemoryEnabled;

    }

    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;

    }

    public ThreadInfo getThreadInfo(long id) {

        long[] ids = new long[1];

        ids[0] = id;

        final ThreadInfo[] infos = getThreadInfo(ids, 0);

        return infos[0];

    }

    public ThreadInfo getThreadInfo(long id, int maxDepth) {

        long[] ids = new long[1];

        ids[0] = id;

        final ThreadInfo[] infos = getThreadInfo(ids, maxDepth);

        return infos[0];

    }

    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]);

            }

        }

    }

    public ThreadInfo[] getThreadInfo(long[] ids, int maxDepth) {

        verifyThreadIds(ids);

        if (maxDepth < 0) {

            throw new IllegalArgumentException(

                "Invalid maxDepth parameter: " + maxDepth);

        }

        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;

    }

    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();

    }

    public long getCurrentThreadCpuTime() {

        if (verifyCurrentThreadCpuTime()) {

            return getThreadTotalCpuTime0(0);

        }

        return -1;

    }

    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();

    }

    public 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;

    }

    public long getCurrentThreadUserTime() {

        if (verifyCurrentThreadCpuTime()) {

            return getThreadUserCpuTime0(0);

        }

        return -1;

    }

    public long getThreadUserTime(long id) {

        long[] ids = new long[1];

        ids[0] = id;

        final long[] times = getThreadUserTime(ids);

        return times[0];

    }

    public 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;

    }

    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;

            }

        }

    }

    public 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();

    }

    public 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;

    }

    public 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;

            }

        }

    }

    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;

    }

    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;

    }

    public void resetPeakThreadCount() {

        Util.checkControlAccess();

        resetPeakThreadCount0();

    }

    public boolean isObjectMonitorUsageSupported() {

        return jvm.isObjectMonitorUsageSupported();

    }

    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();

    }

    public ThreadInfo[] getThreadInfo(long[] ids,

                                      boolean lockedMonitors,

                                      boolean lockedSynchronizers) {

        verifyThreadIds(ids);

        verifyDumpThreads(lockedMonitors, lockedSynchronizers);

        return dumpThreads0(ids, lockedMonitors, lockedSynchronizers);

    }

    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);

    public ObjectName getObjectName() {

        return Util.newObjectName(ManagementFactory.THREAD_MXBEAN_NAME);

    }

}