test/src/org/apache/cordova/test/util/PollingCheck.java

/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.cordova.test.util;

import java.util.concurrent.Callable;

import junit.framework.Assert;

public abstract class PollingCheck {
	private static final long TIME_SLICE = 50;
	private long mTimeout = 3000;

	public PollingCheck() {
	}

	public PollingCheck(long timeout) {
		mTimeout = timeout;
	}

	protected abstract boolean check();

	public void run() {
		if (check()) {
			return;
		}

		long timeout = mTimeout;
		while (timeout > 0) {
			try {
				Thread.sleep(TIME_SLICE);
			} catch (InterruptedException e) {
				Assert.fail("unexpected InterruptedException");
			}

			if (check()) {
				return;
			}

			timeout -= TIME_SLICE;
		}

		Assert.fail("unexpected timeout");
	}

	public static void check(CharSequence message, long timeout,
			Callable<Boolean> condition) throws Exception {
		while (timeout > 0) {
			if (condition.call()) {
				return;
			}

			Thread.sleep(TIME_SLICE);
			timeout -= TIME_SLICE;
		}

		Assert.fail(message.toString());
	}
}