Add adapter from AHC ListenableFuture to Guava one, close AsyncHttpClient#240, close AsyncHttpClient#98

Author: Stephane Landelle

pom.xml

@@ -90,6 +90,13 @@
             <version>1.6.2</version>
         </dependency>
 
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+            <version>11.0.2</version>
+            <optional>true</optional>
+        </dependency>
+
         <!-- Test dependencies -->
         <dependency>
             <groupId>ch.qos.logback</groupId>

src/main/java/com/ning/http/client/extra/ListenableFutureAdapter.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2010-2012 Sonatype, Inc. All rights reserved.
+ *
+ * This program is licensed to you under the Apache License Version 2.0,
+ * and you may not use this file except in compliance with the Apache License Version 2.0.
+ * You may obtain a copy of the Apache License Version 2.0 at http://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the Apache License Version 2.0 is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the Apache License Version 2.0 for the specific language governing permissions and limitations there under.
+ */
+package com.ning.http.client.extra;
+
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Executor;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+import com.ning.http.client.ListenableFuture;
+
+public final class ListenableFutureAdapter {
+
+    /**
+     * @param future an AHC ListenableFuture
+     * @return a Guava ListenableFuture
+     */
+    public static <V> com.google.common.util.concurrent.ListenableFuture<V> asGuavaFuture(final ListenableFuture<V> future) {
+
+        return new com.google.common.util.concurrent.ListenableFuture<V>() {
+
+            public boolean cancel(boolean mayInterruptIfRunning) {
+                return future.cancel(mayInterruptIfRunning);
+            }
+
+            public V get() throws InterruptedException, ExecutionException {
+                return future.get();
+            }
+
+            public V get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException {
+                return future.get(timeout, unit);
+            }
+
+            public boolean isCancelled() {
+                return future.isCancelled();
+            }
+
+            public boolean isDone() {
+                return future.isDone();
+            }
+
+            public void addListener(final Runnable runnable, final Executor executor) {
+                future.addListener(runnable, executor);
+            }
+        };
+    }
+}