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diff --git a/guava/src/com/google/common/util/concurrent/ForwardingListenableFuture.java b/guava/src/com/google/common/util/concurrent/ForwardingListenableFuture.java
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+/*
+ * Copyright (C) 2009 The Guava Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.common.util.concurrent;
+
+import com.google.common.base.Preconditions;
+
+import java.util.concurrent.Executor;
+
+/**
+ * A {@link ListenableFuture} which forwards all its method calls to another
+ * future. Subclasses should override one or more methods to modify the behavior
+ * of the backing future as desired per the <a
+ * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
+ *
+ * <p>Most subclasses can just use {@link SimpleForwardingListenableFuture}.
+ *
+ * @param <V> The result type returned by this Future's {@code get} method
+ * 
+ * @author Shardul Deo
+ * @since 4.0
+ */
+public abstract class ForwardingListenableFuture<V> extends ForwardingFuture<V>
+    implements ListenableFuture<V> {
+
+  /** Constructor for use by subclasses. */
+  protected ForwardingListenableFuture() {}
+
+  @Override
+  protected abstract ListenableFuture<V> delegate();
+
+  @Override
+  public void addListener(Runnable listener, Executor exec) {
+    delegate().addListener(listener, exec);
+  }
+
+  /*
+   * TODO(cpovirk): Use standard Javadoc form for SimpleForwarding* class and
+   * constructor
+   */
+  /**
+   * A simplified version of {@link ForwardingListenableFuture} where subclasses
+   * can pass in an already constructed {@link ListenableFuture} 
+   * as the delegate.
+   * 
+   * @since 9.0
+   */
+  public abstract static class SimpleForwardingListenableFuture<V>
+      extends ForwardingListenableFuture<V> {
+    private final ListenableFuture<V> delegate;
+
+    protected SimpleForwardingListenableFuture(ListenableFuture<V> delegate) {
+      this.delegate = Preconditions.checkNotNull(delegate);
+    }
+
+    @Override
+    protected final ListenableFuture<V> delegate() {
+      return delegate;
+    }
+  }
+}