1 /* 2 * Copyright (C) 2011 The Guava Authors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.google.common.util.concurrent; 18 19 import com.google.common.annotations.Beta; 20 21 import java.util.concurrent.ExecutionException; 22 import java.util.concurrent.Future; 23 24 /** 25 * A callback for accepting the results of a {@link java.util.concurrent.Future} 26 * computation asynchronously. 27 * 28 * <p>To attach to a {@link ListenableFuture} use {@link Futures#addCallback}. 29 * 30 * @author Anthony Zana 31 * @since 10.0 32 */ 33 @Beta 34 public interface FutureCallback<V> { 35 /** 36 * Invoked with the result of the {@code Future} computation when it is 37 * successful. 38 */ 39 void onSuccess(V result); 40 41 /** 42 * Invoked when a {@code Future} computation fails or is canceled. 43 * 44 * <p>If the future's {@link Future#get() get} method throws an {@link 45 * ExecutionException}, then the cause is passed to this method. Any other 46 * thrown object is passed unaltered. 47 */ 48 void onFailure(Throwable t); 49 } 50
