JAVA BINDINGS WIP.

mojo/bindings/java/src/org/chromium/mojo/bindings/DelegatingConnectionErrorHandler.java

Index: mojo/bindings/java/src/org/chromium/mojo/bindings/DelegatingConnectionErrorHandler.java
diff --git a/mojo/bindings/java/src/org/chromium/mojo/bindings/DelegatingConnectionErrorHandler.java b/mojo/bindings/java/src/org/chromium/mojo/bindings/DelegatingConnectionErrorHandler.java
new file mode 100644
index 0000000000000000000000000000000000000000..094268677ea21b75ab485194c5f9a02a67efb206
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+++ b/mojo/bindings/java/src/org/chromium/mojo/bindings/DelegatingConnectionErrorHandler.java
@@ -0,0 +1,49 @@
+// Copyright 2014 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.mojo.bindings;
+
+import org.chromium.mojo.system.MojoException;
+
+import java.util.Map;
+import java.util.WeakHashMap;
+
+/**
+ * A {@link ConnectionErrorHandler} that delegate the errors to a list of registered handlers. This
+ * class will use weak pointers to prevent keeping references to any handlers it delegates to.
+ */
+public class DelegatingConnectionErrorHandler implements ConnectionErrorHandler {
+
+    /**
+     * The registered handlers. This uses a {@link WeakHashMap} so that it doesn't prevent the
+     * handler to be garbage collected.
+     */
+    private final Map<ConnectionErrorHandler, Boolean>
+            mHandlers = new WeakHashMap<ConnectionErrorHandler, Boolean>();
+
+    /**
+     * @see ConnectionErrorHandler#onConnectionError(MojoException)
+     */
+    @Override
+    public void onConnectionError(MojoException e) {
+        for (ConnectionErrorHandler handler : mHandlers.keySet()) {
+            handler.onConnectionError(e);
+        }
+    }
+
+    /**
+     * Add a handler that will be notified of any error this object receives.
+     */
+    public void addConnectionErrorHandler(ConnectionErrorHandler handler) {
+        mHandlers.put(handler, Boolean.TRUE);
+    }
+
+    /**
+     * Remove a previously registered handler.
+     */
+    public void removeConnectionErrorHandler(ConnectionErrorHandler handler) {
+        mHandlers.remove(handler);
+    }
+
+}