/**

 * Copyright 2002-2006 the original author or authors.

 * 

 * 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 opentss;



import java.util.concurrent.locks.Condition;

import java.util.concurrent.locks.ReentrantLock;



/**

 * ?Channel?????????????????????????CPU????

 * 

 * @author <a href="mailto:max.h.chen@hotmail.com">Max Chen</a>

 */

final class ReadLock {



	private ReentrantLock lock = new ReentrantLock();

	private Condition blockedReading = lock.newCondition();

	private boolean isBlockedReading = true;

	

	void blockedReading() {

		lock.lock();

		try {

			isBlockedReading = true;

		} finally {

			lock.unlock();

		}

	}

	

	void unblockedReading() {

		lock.lock();

		try {

			isBlockedReading = false;

			blockedReading.signalAll();

		} finally {

			lock.unlock();

		}

	}

	

	void readyToReadData() {

		lock.lock();

		try {

			while (isBlockedReading)

				blockedReading.await();

		} catch (InterruptedException ie) {

			// ignore

		} finally {

			lock.unlock();

		}

	}

}