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Diffstat (limited to 'libjava/gnu/java/lang/management/VMThreadMXBeanImpl.java')
| -rw-r--r-- | libjava/gnu/java/lang/management/VMThreadMXBeanImpl.java | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/libjava/gnu/java/lang/management/VMThreadMXBeanImpl.java b/libjava/gnu/java/lang/management/VMThreadMXBeanImpl.java new file mode 100644 index 00000000000..3478372c6c5 --- /dev/null +++ b/libjava/gnu/java/lang/management/VMThreadMXBeanImpl.java @@ -0,0 +1,233 @@ +/* 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 long[] findMonitorDeadlockedThreads() + { + return new long[0]; + } + + /* 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 long getCurrentThreadCpuTime() + { + return -1; + } + + /** + * 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 long getCurrentThreadUserTime() + { + return -1; + } + + /** + * 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 int getPeakThreadCount() + { + return -1; + } + + /** + * 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 long getThreadCpuTime(long id) + { + return -1; + } + + /** + * 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 ThreadInfo getThreadInfoForId(long id, int maxDepth) + { + return null; + } + + /** + * 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 long getThreadUserTime(long id) + { + return -1; + } + + /** + * 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 long getTotalStartedThreadCount() + { + return -1; + } + + /** + * Resets the peak thread count to the current + * number of live threads. + */ + static void resetPeakThreadCount() + { + } + +} |