com.twitter.distributedlog.lock.LockWaiter Maven / Gradle / Ivy
/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 com.twitter.distributedlog.lock;
import com.twitter.util.Await;
import com.twitter.util.Duration;
import com.twitter.util.Future;
import com.twitter.util.Timer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Lock waiter represents the attempt that application tries to lock.
*/
public class LockWaiter {
private static final Logger logger = LoggerFactory.getLogger(LockWaiter.class);
private final String lockId;
private final String currentOwner;
private final Future acquireFuture;
public LockWaiter(String lockId,
String currentOwner,
Future acquireFuture) {
this.lockId = lockId;
this.currentOwner = currentOwner;
this.acquireFuture = acquireFuture;
}
/**
* Return the lock id of the waiter.
*
* @return lock id of the waiter
*/
public String getId() {
return lockId;
}
/**
* Return the owner that observed when waiter is waiting.
*
* @return the owner that observed when waiter is waiting
*/
public String getCurrentOwner() {
return currentOwner;
}
/**
* Return the future representing the waiting result.
*
* If the future is interrupted (e.g. {@link Future#within(Duration, Timer)}),
* the waiter will automatically clean up its waiting state.
*
* @return the future representing the acquire result.
*/
public Future getAcquireFuture() {
return acquireFuture;
}
/**
* Wait for the acquire result.
*
* @return true if acquired successfully, otherwise false.
*/
public boolean waitForAcquireQuietly() {
boolean success = false;
try {
success = Await.result(acquireFuture);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
} catch (LockTimeoutException lte) {
logger.debug("Timeout on lock acquiring", lte);
} catch (Exception e) {
logger.error("Caught exception waiting for lock acquired", e);
}
return success;
}
}