--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/agent/src/share/classes/sun/jvm/hotspot/utilities/LivenessPath.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,108 @@
+/*
+ * Copyright 2001-2006 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.utilities;
+
+import java.io.*;
+import java.util.*;
+import sun.jvm.hotspot.oops.*;
+
+/** Describes a path from an object back to the root which is keeping
+    it alive. Elements of the path are (object, field) pairs, where
+    the object is expressed as a @link{sun.jvm.hotspot.oops.Oop}, and
+    where the field is expressed as a
+    @link{sun.jvm.hotspot.oops.FieldIdentifier}. If the element
+    reflects a root, the Oop will be null. If the element is the end
+    of the path, the FieldIdentifier will be null. */
+
+public class LivenessPath {
+  LivenessPath() {
+    stack = new Stack();
+  }
+
+  /** Number of elements in the path */
+  public int size() {
+    return stack.size();
+  }
+
+  /** Fetch the element at the given index; 0-based */
+  public LivenessPathElement get(int index) throws ArrayIndexOutOfBoundsException {
+    return (LivenessPathElement) stack.get(index);
+  }
+
+  public void printOn(PrintStream tty) {
+    for (int j = 0; j < size(); j++) {
+      LivenessPathElement el = get(j);
+      tty.print("  - ");
+      if (el.getObj() != null) {
+        Oop.printOopValueOn(el.getObj(), tty);
+      }
+      if (el.getField() != null) {
+        if (el.getObj() != null) {
+          tty.print(", field ");
+        }
+        tty.print(el.getField().getName());
+      }
+      tty.println();
+    }
+  }
+
+  /** Indicates whether this path is "complete", i.e., whether the
+      last element is a root. Convenience routine for LivenessAnalysis. */
+  boolean isComplete() {
+    if (size() == 0)
+      return false;
+    return peek().isRoot();
+  }
+
+  // Convenience routine for LivenessAnalysis
+  LivenessPathElement peek() {
+    return (LivenessPathElement) stack.peek();
+  }
+
+  // Convenience routine for LivenessAnalysis
+  void push(LivenessPathElement el) {
+    stack.push(el);
+  }
+
+  // Convenience routine for LivenessAnalysis
+  void pop() {
+    stack.pop();
+  }
+
+  // Make a copy of the contents of the path -- the
+  // LivenessPathElements are not duplicated, only the containing path
+  LivenessPath copy() {
+    LivenessPath dup = new LivenessPath();
+    for (int i = 0; i < stack.size(); i++) {
+      dup.stack.push(stack.get(i));
+    }
+    return dup;
+  }
+
+  //---------------------------------------------------------------------------
+  // Internals only below this point
+  //
+  private Stack stack;
+}