--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/org.chromium.sdk/src/org/chromium/sdk/internal/tools/v8/MethodIsBlockingException.java	Wed Dec 23 17:13:18 2009 -0800
@@ -0,0 +1,44 @@
+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.sdk.internal.tools.v8;
+
+/**
+ * Signals that a deadlock was about to happen.
+ * <p>
+ * Method may wait for some callback to receive a result from some worker
+ * thread. If this method happened to be called from another callback
+ * being run by the same thread this will block the thread forever because
+ * method is never going to get result. Such situation may raise this
+ * exception.
+ * <p>
+ * Currently this exception is never actually thrown so it gets more of
+ * symbolic sense. Nevertheless it's still important to keep its declaration
+ * because it helps to track which ones are blocking and which are not.
+ * To do this, one should temporary modify this class and make exception checked
+ * (make it extend {@code java.lang.Exception}). This will enforce the proper
+ * declaration of all blocking methods.
+ * <p>Here are the simple rules: you never normally catch this exception, but
+ * add throws declaration wherever needed; if your callback method needs to
+ * throw it you are doing something wrong (i.e. calling blocking method from
+ * a callback) and risk running into a deadlock; wherever you are
+ * sure you are on a safe ground (not called from callback) and there is no
+ * need in further tracking this exception, make a symbolic try/catch and
+ * explain why you think it's safe, in a catch block:
+ * <pre>
+ *   try {
+ *     makeSureAllScriptsAreLoaded();
+ *   } catch (MethodIsBlockingException e) {
+ *     // I'm being called from my own thread, so it's ok if method blocks,
+ *     // I can wait
+ *     throw new RuntimeException(e); // never executed
+ *   }
+ * </pre>
+ * <p>By default, {@code MethodIsBlockingException} is unchecked exception,
+ * so you may completely ignore it.
+ */
+public class MethodIsBlockingException extends RuntimeException {
+  // We never actually instantiate this exception, because it's symbolic.
+  private MethodIsBlockingException() {}
+}