1 files changed, 62 insertions, 0 deletions
diff --git a/src/main/javassist/runtime/Cflow.java b/src/main/javassist/runtime/Cflow.java
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+++ b/src/main/javassist/runtime/Cflow.java
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+/*
+ * This file is part of the Javassist toolkit.
+ *
+ * The contents of this file are subject to the Mozilla Public License
+ * Version 1.1 (the "License"); you may not use this file except in
+ * compliance with the License.  You may obtain a copy of the License at
+ * either http://www.mozilla.org/MPL/.
+ *
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.  See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * The Original Code is Javassist.
+ *
+ * The Initial Developer of the Original Code is Shigeru Chiba.  Portions
+ * created by Shigeru Chiba are Copyright (C) 1999-2003 Shigeru Chiba.
+ * All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * The development of this software is supported in part by the PRESTO
+ * program (Sakigake Kenkyu 21) of Japan Science and Technology Corporation.
+ */
+
+package javassist.runtime;
+
+/**
+ * A support class for implementing <code>$cflow</code>.
+ * This support class is required at runtime
+ * only if <code>$cflow</code> is used.
+ *
+ * @see javassist.CtBehavior#useCflow(String)
+ */
+public class Cflow extends ThreadLocal {
+    private static class Depth {
+	private int depth;
+	Depth() { depth = 0; }
+	int get() { return depth; }
+	void inc() { ++depth; }
+	void dec() { --depth; }
+    }
+
+    protected synchronized Object initialValue() {
+	return new Depth();
+    }
+
+    /**
+     * Increments the counter.
+     */
+    public void enter() { ((Depth)get()).inc(); }
+
+    /**
+     * Decrements the counter.
+     */
+    public void exit() { ((Depth)get()).dec(); }
+
+    /**
+     * Returns the value of the counter.
+     */
+    public int value() { return ((Depth)get()).get(); }
+}