| /* VMThreadMXBeanImpl.java - VM impl. of a thread bean |
| Copyright (C) 2006 Free Software Foundation |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package gnu.java.lang.management; |
| |
| import java.lang.management.ThreadInfo; |
| |
| /** |
| * Provides access to information about the threads |
| * of the virtual machine. An instance of this bean is |
| * obtained by calling |
| * {@link ManagementFactory#getThreadMXBean()}. |
| * See {@link java.lang.management.ThreadMXBean} for |
| * full documentation. |
| * |
| * @author Andrew John Hughes (gnu_andrew@member.fsf.org) |
| * @since 1.5 |
| */ |
| final class VMThreadMXBeanImpl |
| { |
| |
| /** |
| * Cache of how many threads were found. |
| */ |
| private static int filled; |
| |
| /** |
| * Returns the ids of cycles of deadlocked threads, occurring |
| * due to monitor ownership. |
| * |
| * @return the ids of the deadlocked threads. |
| */ |
| static native long[] findMonitorDeadlockedThreads(); |
| |
| /* This is the same as in Thread.getAllStackTraces() */ |
| static Thread[] getAllThreads() |
| { |
| ThreadGroup group = Thread.currentThread().getThreadGroup(); |
| while (group.getParent() != null) |
| group = group.getParent(); |
| int arraySize = group.activeCount(); |
| Thread[] threadList = new Thread[arraySize]; |
| filled = group.enumerate(threadList); |
| while (filled == arraySize) |
| { |
| arraySize *= 2; |
| threadList = new Thread[arraySize]; |
| filled = group.enumerate(threadList); |
| } |
| return threadList; |
| } |
| |
| /** |
| * Returns the id of all live threads at the time of execution. |
| * |
| * @return the live thread ids. |
| */ |
| static long[] getAllThreadIds() |
| { |
| Thread[] threadList = getAllThreads(); |
| long[] ids = new long[filled]; |
| for (int a = 0; a < filled; ++a) |
| ids[a] = threadList[a].getId(); |
| return ids; |
| } |
| |
| /** |
| * Returns the number of nanoseconds of CPU time |
| * the current thread has used in total. This is |
| * only called if this feature is enabled and |
| * supported. |
| * |
| * @return the nanoseconds of CPU time used by |
| * the current thread. |
| */ |
| static native long getCurrentThreadCpuTime(); |
| |
| /** |
| * Returns the number of nanoseconds of user time |
| * the current thread has used in total. This is |
| * only called if this feature is enabled and |
| * supported. |
| * |
| * @return the nanoseconds of user time used by |
| * the current thread. |
| */ |
| static native long getCurrentThreadUserTime(); |
| |
| /** |
| * Returns the number of live daemon threads. |
| * |
| * @return the number of live daemon threads. |
| */ |
| static int getDaemonThreadCount() |
| { |
| Thread[] threadList = getAllThreads(); |
| int daemonCount = 0; |
| for (int a = 0; a < filled; ++a) |
| { |
| if (threadList[a].isDaemon()) |
| ++daemonCount; |
| } |
| return daemonCount; |
| } |
| |
| /** |
| * Returns the current peak number of live threads. |
| * |
| * @return the peak number of live threads. |
| */ |
| static native int getPeakThreadCount(); |
| |
| /** |
| * Returns the number of live threads. |
| * |
| * @return the number of live threads. |
| */ |
| static int getThreadCount() |
| { |
| getAllThreads(); |
| return filled; |
| } |
| |
| /** |
| * Returns the number of nanoseconds of CPU time |
| * the specified thread has used in total. This is |
| * only called if this feature is enabled and |
| * supported. |
| * |
| * @param id the thread to obtain statistics on. |
| * @return the nanoseconds of CPU time used by |
| * the thread. |
| */ |
| static native long getThreadCpuTime(long id); |
| |
| /** |
| * Returns the {@link java.lang.management.ThreadInfo} |
| * which corresponds to the specified id. |
| * |
| * @param id the id of the thread. |
| * @param maxDepth the depth of the stack trace. |
| * @return the corresponding <code>ThreadInfo</code>. |
| */ |
| static native ThreadInfo getThreadInfoForId(long id, int maxDepth); |
| |
| /** |
| * Returns the number of nanoseconds of user time |
| * the specified thread has used in total. This is |
| * only called if this feature is enabled and |
| * supported. |
| * |
| * @param id the thread to obtain statistics on. |
| * @return the nanoseconds of user time used by |
| * the thread. |
| */ |
| static native long getThreadUserTime(long id); |
| |
| /** |
| * Returns the total number of threads that have |
| * been started over the lifetime of the virtual |
| * machine. |
| * |
| * @return the total number of threads started. |
| */ |
| static native long getTotalStartedThreadCount(); |
| |
| /** |
| * Resets the peak thread count to the current |
| * number of live threads. |
| */ |
| static native void resetPeakThreadCount(); |
| |
| } |