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diff --git a/guava/src/com/google/common/reflect/AbstractInvocationHandler.java b/guava/src/com/google/common/reflect/AbstractInvocationHandler.java
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+++ b/guava/src/com/google/common/reflect/AbstractInvocationHandler.java
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+/*
+ * Copyright (C) 2012 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.reflect;
+
+import com.google.common.annotations.Beta;
+
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.Method;
+import java.lang.reflect.Proxy;
+
+import javax.annotation.Nullable;
+
+/**
+ * Abstract implementation of {@link InvocationHandler} that handles {@link Object#equals},
+ * {@link Object#hashCode} and {@link Object#toString}.
+ *
+ * @author Ben Yu
+ * @since 12.0
+ */
+@Beta
+public abstract class AbstractInvocationHandler implements InvocationHandler {
+
+  private static final Object[] NO_ARGS = {};
+
+  /**
+   * {@inheritDoc}
+   *
+   * <p><ul>
+   * <li>{@code proxy.hashCode()} delegates to {@link AbstractInvocationHandler#hashCode}
+   * <li>{@code proxy.toString()} delegates to {@link AbstractInvocationHandler#toString}
+   * <li>{@code proxy.equals(argument)} returns true if: <ul>
+   *   <li>{@code proxy} and {@code argument} are of the same type
+   *   <li>and {@link AbstractInvocationHandler#equals} returns true for the {@link
+   *       InvocationHandler} of {@code argument}
+   *   </ul>
+   * <li>other method calls are dispatched to {@link #handleInvocation}.
+   * </ul>
+   */
+  @Override public final Object invoke(Object proxy, Method method, @Nullable Object[] args)
+      throws Throwable {
+    if (args == null) {
+      args = NO_ARGS;
+    }
+    if (args.length == 0 && method.getName().equals("hashCode")) {
+      return hashCode();
+    }
+    if (args.length == 1
+        && method.getName().equals("equals")
+        && method.getParameterTypes()[0] == Object.class) {
+      Object arg = args[0];
+      return proxy.getClass().isInstance(arg) && equals(Proxy.getInvocationHandler(arg));
+    }
+    if (args.length == 0 && method.getName().equals("toString")) {
+      return toString();
+    }
+    return handleInvocation(proxy, method, args);
+  }
+
+  /**
+   * {@link #invoke} delegates to this method upon any method invocation on the proxy instance,
+   * except {@link Object#equals}, {@link Object#hashCode} and {@link Object#toString}. The result
+   * will be returned as the proxied method's return value.
+   * 
+   * <p>Unlike {@link #invoke}, {@code args} will never be null. When the method has no parameter,
+   * an empty array is passed in.
+   */
+  protected abstract Object handleInvocation(Object proxy, Method method, Object[] args)
+      throws Throwable;
+
+  /**
+   * By default delegates to {@link Object#equals} so instances are only equal if they are
+   * identical. {@code proxy.equals(argument)} returns true if: <ul>
+   * <li>{@code proxy} and {@code argument} are of the same type
+   * <li>and this method returns true for the {@link InvocationHandler} of {@code argument}
+   * </ul>
+   * Subclasses can override this method to provide custom equality.
+   */
+  @Override public boolean equals(Object obj) {
+    return super.equals(obj);
+  }
+
+  /**
+   * By default delegates to {@link Object#hashCode}. The dynamic proxies' {@code hashCode()} will
+   * delegate to this method. Subclasses can override this method to provide custom equality.
+   */
+  @Override public int hashCode() {
+    return super.hashCode();
+  }
+
+  /**
+   * By default delegates to {@link Object#toString}. The dynamic proxies' {@code toString()} will
+   * delegate to this method. Subclasses can override this method to provide custom string
+   * representation for the proxies.
+   */
+  @Override public String toString() {
+    return super.toString();
+  }
+}