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Core services for Usergrid system.
/*******************************************************************************
* Copyright 2012 Apigee Corporation
*
* 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.usergrid.locking.cassandra;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
import me.prettyprint.hector.api.locking.HLock;
import me.prettyprint.hector.api.locking.HLockManager;
import me.prettyprint.hector.api.locking.HLockTimeoutException;
import org.usergrid.locking.Lock;
import org.usergrid.locking.exception.UGLockException;
/**
* @author tnine
*
*/
public class HectorLockImpl implements Lock {
private HLock lock;
private HLockManager lm;
private AtomicInteger count = new AtomicInteger();
/**
*
*/
public HectorLockImpl(HLock lock, HLockManager lm) {
this.lock = lock;
this.lm = lm;
}
/* (non-Javadoc)
* @see org.usergrid.locking.Lock#acquire(long, java.util.concurrent.TimeUnit)
*/
@Override
public boolean tryLock(long timeout, TimeUnit time) throws UGLockException {
try{
lm.acquire(this.lock, time.toMillis(timeout));
count.incrementAndGet();
}catch(HLockTimeoutException hlte){
return false;
}
return true;
}
/* (non-Javadoc)
* @see org.usergrid.locking.Lock#lock()
*/
@Override
public void lock() throws UGLockException {
lm.acquire(lock);
count.incrementAndGet();
}
/* (non-Javadoc)
* @see org.usergrid.locking.Lock#release()
*/
@Override
public void unlock() throws UGLockException {
int current = count.decrementAndGet();
if(current == 0){
lm.release(this.lock);
}
}
}