Java 中的编程死锁检测

您可以使用 JDK 附带的 编程方式执行此操作：ThreadMXBean

ThreadMXBean bean = ManagementFactory.getThreadMXBean();
long[] threadIds = bean.findDeadlockedThreads(); // Returns null if no threads are deadlocked.

if (threadIds != null) {
    ThreadInfo[] infos = bean.getThreadInfo(threadIds);

    for (ThreadInfo info : infos) {
        StackTraceElement[] stack = info.getStackTrace();
        // Log or store stack trace information.
    }
}

显然，您应该尝试隔离正在执行此死锁检查的任何线程 - 否则，如果该线程死锁，它将无法运行检查！

顺便说一句，这就是JConsole在幕后使用的东西。

一个有用的调查提示：

如果您可以抓住应用程序并怀疑发生了死锁，请在java.exe控制台窗口中按“Ctrl-Break”（或在Solaris/Linux上按“Ctrl-Break”）。jvm将转储所有线程的当前状态和堆栈跟踪，找出死锁并精确描述它们。

它看起来像这样：

Full thread dump Java HotSpot(TM) Client VM (1.5.0_09-b03 mixed mode):

"[Test Timer] Request Queue" prio=6 tid=0x13d708d0 nid=0x1ec in Object.
    wait() [0x1b00f000..0x1b00fb68]
    at java.lang.Object.wait(Native Method)
    at java.lang.Object.wait(Unknown Source)
    at library.util.AsyncQueue.run(AsyncQueue.java:138)
        - locked <0x02e70000> (a test.server.scheduler.SchedulerRequestQueue)

    ...

Found one Java-level deadlock:
=============================
"Corba service":
  waiting to lock monitor 0x13c06684 (object 0x04697d90, a java.lang.Object),
  which is held by "[Server Connection] Heartbeat Timer"
"[Server Connection] Heartbeat Timer":
  waiting to lock monitor 0x13c065c4 (object 0x0467e728, a test.proxy.ServerProxy), which is held by "Corba service"

Java stack information for the threads listed above:
===================================================
"Corba service":
    at test.proxy.ServerProxy.stopHBWatchDog(ServerProxy:695)
    - waiting to lock <0x04697d90> (a java.lang.Object)
    ...