/*
* 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 gobblin.runtime.locks;
import java.io.Closeable;
import java.util.Properties;
/**
* A interface for claiming exclusive right to proceed for each scheduled
* run of a job.
*
* <p>
* By acquiring a {@link JobLock} before a scheduled run of a job
* can proceed, it is guaranteed that no more than one instance of
* a job is running at any time.
* </p>
*
* @author Yinan Li
*/
public interface JobLock extends Closeable {
/**
* Acquire the lock.
*
* @throws JobLockException thrown if the {@link JobLock} fails to be acquired
*/
void lock()
throws JobLockException;
/**
* Release the lock.
*
* @throws JobLockException thrown if the {@link JobLock} fails to be released
*/
void unlock()
throws JobLockException;
/**
* Try locking the lock.
*
* @return <em>true</em> if the lock is successfully locked,
* <em>false</em> if otherwise.
* @throws JobLockException thrown if the {@link JobLock} fails to be acquired
*/
boolean tryLock()
throws JobLockException;
/**
* Check if the lock is locked.
*
* @return if the lock is locked
* @throws JobLockException thrown if checking the status of the {@link JobLock} fails
*/
boolean isLocked()
throws JobLockException;
}