--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/agent/src/share/classes/sun/jvm/hotspot/runtime/ConcurrentLocksPrinter.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,87 @@
+/*
+ * Copyright 2005 Sun Microsystems, Inc.  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.
+ *
+ * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+package sun.jvm.hotspot.runtime;
+
+import java.io.*;
+import java.util.*;
+import sun.jvm.hotspot.memory.*;
+import sun.jvm.hotspot.oops.*;
+
+public class ConcurrentLocksPrinter {
+    private Map locksMap = new HashMap(); // <JavaThread, List<Oop>>
+
+    public ConcurrentLocksPrinter() {
+        fillLocks();
+    }
+
+    public void print(JavaThread jthread, PrintStream tty) {
+        List locks = (List) locksMap.get(jthread);
+        tty.println("Locked ownable synchronizers:");
+        if (locks == null || locks.isEmpty()) {
+            tty.println("    - None");
+        } else {
+            for (Iterator itr = locks.iterator(); itr.hasNext();) {
+                Oop oop = (Oop) itr.next();
+                tty.println("    - <" + oop.getHandle() + ">, (a " +
+                       oop.getKlass().getName().asString() + ")");
+            }
+        }
+    }
+
+    //-- Internals only below this point
+    private JavaThread getOwnerThread(Oop oop) {
+        Oop threadOop = OopUtilities.abstractOwnableSynchronizerGetOwnerThread(oop);
+        if (threadOop == null) {
+            return null;
+        } else {
+            return OopUtilities.threadOopGetJavaThread(threadOop);
+        }
+    }
+
+    private void fillLocks() {
+        VM vm = VM.getVM();
+        SystemDictionary sysDict = vm.getSystemDictionary();
+        Klass absOwnSyncKlass = sysDict.getAbstractOwnableSynchronizerKlass();
+        ObjectHeap heap = vm.getObjectHeap();
+        // may be not loaded at all
+        if (absOwnSyncKlass != null) {
+            heap.iterateObjectsOfKlass(new DefaultHeapVisitor() {
+                    public boolean doObj(Oop oop) {
+                        JavaThread thread = getOwnerThread(oop);
+                        if (thread != null) {
+                            List locks = (List) locksMap.get(thread);
+                            if (locks == null) {
+                                locks = new LinkedList();
+                                locksMap.put(thread, locks);
+                            }
+                            locks.add(oop);
+                        }
+                        return false;
+                    }
+
+                }, absOwnSyncKlass, true);
+        }
+    }
+}