Added deadlock detection

src/main/NGECore.java

@@ -34,6 +34,7 @@ import java.util.concurrent.ConcurrentHashMap;
 
 
 import resources.common.RadialOptions;
+import resources.common.ThreadMonitor;
 import resources.objects.creature.CreatureObject;
 import services.AttributeService;
 import services.BuffService;
@@ -145,6 +146,20 @@ public class NGECore {
 	public void start() {
 		
 		instance = this;
+		
+		final ThreadMonitor deadlockDetector = new ThreadMonitor();
+		Thread deadlockMonitor = new Thread(new Runnable() {
+			@Override
+			public void run() {
+				try {
+					deadlockDetector.findDeadlock();
+					Thread.sleep(60000);
+				} catch (InterruptedException e) {
+					e.printStackTrace();
+				}
+			}
+		});
+		deadlockMonitor.start();
 		config = new Config();
 		config.setFilePath("nge.cfg");
 		if (!(config.loadConfigFile())) {

src/resources/common/ThreadMonitor.java

@@ -0,0 +1,226 @@
+/*******************************************************************************
+ * Copyright (c) 2013 <Project SWG>
+ * 
+ * This File is part of NGECore2.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program 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 Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ * 
+ * Using NGEngine to work with NGECore2 is making a combined work based on NGEngine. 
+ * Therefore all terms and conditions of the GNU Lesser General Public License cover the combination.
+ ******************************************************************************/
+package resources.common;
+
+import static java.lang.management.ManagementFactory.THREAD_MXBEAN_NAME;
+import static java.lang.management.ManagementFactory.getThreadMXBean;
+import static java.lang.management.ManagementFactory.newPlatformMXBeanProxy;
+
+import java.io.IOException;
+import java.lang.management.LockInfo;
+import java.lang.management.MonitorInfo;
+import java.lang.management.ThreadInfo;
+import java.lang.management.ThreadMXBean;
+import java.util.concurrent.BrokenBarrierException;
+import java.util.concurrent.CyclicBarrier;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+import javax.management.InstanceNotFoundException;
+import javax.management.IntrospectionException;
+import javax.management.MBeanOperationInfo;
+import javax.management.MBeanServerConnection;
+import javax.management.MalformedObjectNameException;
+import javax.management.ObjectName;
+import javax.management.ReflectionException;
+
+public class ThreadMonitor {
+	
+	  private MBeanServerConnection server;
+
+	  private ThreadMXBean tmbean;
+
+	  private ObjectName objname;
+
+	  // default - JDK 6+ VM
+	  private String findDeadlocksMethodName = "findDeadlockedThreads";
+
+	  private boolean canDumpLocks = true;
+
+	  /**
+	   * Constructs a ThreadMonitor object to get thread information in the local
+	   * JVM.
+	   */
+	  public ThreadMonitor() {
+	    this.tmbean = getThreadMXBean();
+	  }
+
+	  /**
+	   * Prints the thread dump information to System.out.
+	   */
+	  public void threadDump() {
+	    if (canDumpLocks) {
+	      if (tmbean.isObjectMonitorUsageSupported() && tmbean.isSynchronizerUsageSupported()) {
+	        dumpThreadInfoWithLocks();
+	      }
+	    } else {
+	      dumpThreadInfo();
+	    }
+	  }
+
+	  private void dumpThreadInfo() {
+	    System.out.println("Full Java thread dump");
+	    long[] tids = tmbean.getAllThreadIds();
+	    ThreadInfo[] tinfos = tmbean.getThreadInfo(tids, Integer.MAX_VALUE);
+	    for (ThreadInfo ti : tinfos) {
+	      printThreadInfo(ti);
+	    }
+	  }
+
+	  /**
+	   * Prints the thread dump information with locks info to System.out.
+	   */
+	  private void dumpThreadInfoWithLocks() {
+	    System.out.println("Full Java thread dump with locks info");
+
+	    ThreadInfo[] tinfos = tmbean.dumpAllThreads(true, true);
+	    for (ThreadInfo ti : tinfos) {
+	      printThreadInfo(ti);
+	      LockInfo[] syncs = ti.getLockedSynchronizers();
+	      printLockInfo(syncs);
+	    }
+	    System.out.println();
+	  }
+
+	  private static String INDENT = "    ";
+
+	  private void printThreadInfo(ThreadInfo ti) {
+	    // print thread information
+	    printThread(ti);
+
+	    // print stack trace with locks
+	    StackTraceElement[] stacktrace = ti.getStackTrace();
+	    MonitorInfo[] monitors = ti.getLockedMonitors();
+	    for (int i = 0; i < stacktrace.length; i++) {
+	      StackTraceElement ste = stacktrace[i];
+	      System.out.println(INDENT + "at " + ste.toString());
+	      for (MonitorInfo mi : monitors) {
+	        if (mi.getLockedStackDepth() == i) {
+	          System.out.println(INDENT + "  - locked " + mi);
+	        }
+	      }
+	    }
+	    System.out.println();
+	  }
+
+	  private void printThread(ThreadInfo ti) {
+	    StringBuilder sb = new StringBuilder("\"" + ti.getThreadName() + "\"" + " Id="
+	        + ti.getThreadId() + " in " + ti.getThreadState());
+	    if (ti.getLockName() != null) {
+	      sb.append(" on lock=" + ti.getLockName());
+	    }
+	    if (ti.isSuspended()) {
+	      sb.append(" (suspended)");
+	    }
+	    if (ti.isInNative()) {
+	      sb.append(" (running in native)");
+	    }
+	    System.out.println(sb.toString());
+	    if (ti.getLockOwnerName() != null) {
+	      System.out.println(INDENT + " owned by " + ti.getLockOwnerName() + " Id="
+	          + ti.getLockOwnerId());
+	    }
+	  }
+
+	  private void printMonitorInfo(ThreadInfo ti, MonitorInfo[] monitors) {
+	    System.out.println(INDENT + "Locked monitors: count = " + monitors.length);
+	    for (MonitorInfo mi : monitors) {
+	      System.out.println(INDENT + "  - " + mi + " locked at ");
+	      System.out.println(INDENT + "      " + mi.getLockedStackDepth() + " "
+	          + mi.getLockedStackFrame());
+	    }
+	  }
+
+	  private void printLockInfo(LockInfo[] locks) {
+	    System.out.println(INDENT + "Locked synchronizers: count = " + locks.length);
+	    for (LockInfo li : locks) {
+	      System.out.println(INDENT + "  - " + li);
+	    }
+	    System.out.println();
+	  }
+
+	  /**
+	   * Checks if any threads are deadlocked. If any, print the thread dump
+	   * information.
+	   */
+	  public boolean findDeadlock() {
+	    long[] tids;
+	    if (findDeadlocksMethodName.equals("findDeadlockedThreads")
+	        && tmbean.isSynchronizerUsageSupported()) {
+	      tids = tmbean.findDeadlockedThreads();
+	      if (tids == null) {
+	        return false;
+	      }
+
+	      System.out.println("Deadlock found :-");
+	      ThreadInfo[] infos = tmbean.getThreadInfo(tids, true, true);
+	      for (ThreadInfo ti : infos) {
+	        printThreadInfo(ti);
+	        printLockInfo(ti.getLockedSynchronizers());
+	        System.out.println();
+	      }
+	    } else {
+	      tids = tmbean.findMonitorDeadlockedThreads();
+	      if (tids == null) {
+	        return false;
+	      }
+	      ThreadInfo[] infos = tmbean.getThreadInfo(tids, Integer.MAX_VALUE);
+	      for (ThreadInfo ti : infos) {
+	        // print thread information
+	        printThreadInfo(ti);
+	      }
+	    }
+
+	    return true;
+	  }
+
+	  private void parseMBeanInfo() throws IOException {
+	    try {
+	      MBeanOperationInfo[] mopis = server.getMBeanInfo(objname).getOperations();
+
+	      // look for findDeadlockedThreads operations;
+	      boolean found = false;
+	      for (MBeanOperationInfo op : mopis) {
+	        if (op.getName().equals(findDeadlocksMethodName)) {
+	          found = true;
+	          break;
+	        }
+	      }
+	      if (!found) {
+	        findDeadlocksMethodName = "findMonitorDeadlockedThreads";
+	        canDumpLocks = false;
+	      }
+	    } catch (IntrospectionException e) {
+	      InternalError ie = new InternalError(e.getMessage());
+	      ie.initCause(e);
+	      throw ie;
+	    } catch (InstanceNotFoundException e) {
+	      InternalError ie = new InternalError(e.getMessage());
+	      ie.initCause(e);
+	      throw ie;
+	    } catch (ReflectionException e) {
+	      InternalError ie = new InternalError(e.getMessage());
+	      ie.initCause(e);
+	      throw ie;
+	    }
+	  }
+	}