1 /* 2 * Copyright (C) 2017 The Android Open Source Project 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.googlecode.android_scripting.future; 18 19 import java.util.concurrent.CountDownLatch; 20 import java.util.concurrent.Future; 21 import java.util.concurrent.TimeUnit; 22 23 /** 24 * FutureResult represents an eventual execution result for asynchronous operations. 25 * 26 */ 27 public class FutureResult<T> implements Future<T> { 28 29 private final CountDownLatch mLatch = new CountDownLatch(1); 30 private volatile T mResult = null; 31 set(T result)32 public void set(T result) { 33 mResult = result; 34 mLatch.countDown(); 35 } 36 37 @Override cancel(boolean mayInterruptIfRunning)38 public boolean cancel(boolean mayInterruptIfRunning) { 39 return false; 40 } 41 42 @Override get()43 public T get() throws InterruptedException { 44 mLatch.await(); 45 return mResult; 46 } 47 48 @Override get(long timeout, TimeUnit unit)49 public T get(long timeout, TimeUnit unit) throws InterruptedException { 50 mLatch.await(timeout, unit); 51 return mResult; 52 } 53 54 @Override isCancelled()55 public boolean isCancelled() { 56 return false; 57 } 58 59 @Override isDone()60 public boolean isDone() { 61 return mResult != null; 62 } 63 64 } 65