1 /* 2 * Copyright (C) 2012 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 android.cts.util; 18 19 import java.util.concurrent.Callable; 20 21 import junit.framework.Assert; 22 23 public abstract class PollingCheck { 24 private static final long TIME_SLICE = 50; 25 private long mTimeout = 3000; 26 27 public static interface PollingCheckCondition { 28 boolean canProceed(); 29 } 30 31 public PollingCheck() { 32 } 33 34 public PollingCheck(long timeout) { 35 mTimeout = timeout; 36 } 37 38 protected abstract boolean check(); 39 40 public void run() { 41 if (check()) { 42 return; 43 } 44 45 long timeout = mTimeout; 46 while (timeout > 0) { 47 try { 48 Thread.sleep(TIME_SLICE); 49 } catch (InterruptedException e) { 50 Assert.fail("unexpected InterruptedException"); 51 } 52 53 if (check()) { 54 return; 55 } 56 57 timeout -= TIME_SLICE; 58 } 59 60 Assert.fail("unexpected timeout"); 61 } 62 63 public static void check(CharSequence message, long timeout, Callable<Boolean> condition) 64 throws Exception { 65 while (timeout > 0) { 66 if (condition.call()) { 67 return; 68 } 69 70 Thread.sleep(TIME_SLICE); 71 timeout -= TIME_SLICE; 72 } 73 74 Assert.fail(message.toString()); 75 } 76 77 public static void waitFor(final PollingCheckCondition condition) { 78 new PollingCheck() { 79 @Override 80 protected boolean check() { 81 return condition.canProceed(); 82 } 83 }.run(); 84 } 85 } 86