1 /* 2 * ==================================================================== 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, 14 * software distributed under the License is distributed on an 15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16 * KIND, either express or implied. See the License for the 17 * specific language governing permissions and limitations 18 * under the License. 19 * ==================================================================== 20 * 21 * This software consists of voluntary contributions made by many 22 * individuals on behalf of the Apache Software Foundation. For more 23 * information on the Apache Software Foundation, please see 24 * <http://www.apache.org/>. 25 * 26 */ 27 package org.apache.hc.core5.concurrent; 28 29 import java.util.concurrent.Future; 30 import java.util.concurrent.TimeUnit; 31 32 import org.apache.hc.core5.annotation.Contract; 33 import org.apache.hc.core5.annotation.ThreadingBehavior; 34 35 /** 36 * Immutable, completed future. 37 * 38 * @param <T> the future result type of an asynchronous operation. 39 * @since 5.0 40 */ 41 @Contract(threading = ThreadingBehavior.IMMUTABLE) 42 public class CompletedFuture<T> implements Future<T>, Cancellable { 43 44 private final T result; 45 46 public CompletedFuture(final T result) { 47 super(); 48 this.result = result; 49 } 50 51 @Override 52 public boolean isCancelled() { 53 return false; 54 } 55 56 @Override 57 public boolean isDone() { 58 return true; 59 } 60 61 @Override 62 public T get() { 63 return this.result; 64 } 65 66 @Override 67 public T get(final long timeout, final TimeUnit unit) { 68 return this.result; 69 } 70 71 @Override 72 public boolean cancel(final boolean mayInterruptIfRunning) { 73 return false; 74 } 75 76 @Override 77 public boolean cancel() { 78 return false; 79 } 80 81 }