/*
* JBoss, Home of Professional Open Source.
* Copyright 2010, Red Hat, Inc., and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.as.ejb3.concurrency;
import org.jboss.invocation.Interceptor;
import org.jboss.invocation.InterceptorContext;
import org.jboss.logging.Logger;
import javax.ejb.LockType;
import javax.interceptor.InvocationContext;
import java.lang.reflect.Method;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReadWriteLock;
import static org.jboss.as.ejb3.EjbMessages.MESSAGES;
import static org.jboss.as.ejb3.EjbLogger.ROOT_LOGGER;
/**
* @author Jaikiran Pai
*/
public class ContainerManagedConcurrencyInterceptor implements Interceptor {
/**
* Logger
*/
private static final Logger logger = Logger.getLogger(ContainerManagedConcurrencyInterceptor.class);
/**
* A spec compliant {@link org.jboss.as.ejb3.concurrency.EJBReadWriteLock}
*/
private final ReadWriteLock readWriteLock = new EJBReadWriteLock();
private final LockableComponent lockableComponent;
public ContainerManagedConcurrencyInterceptor(LockableComponent component) {
if (component == null) {
throw MESSAGES.componentIsNull(LockableComponent.class.getName());
}
this.lockableComponent = component;
}
protected LockableComponent getLockableComponent() {
return this.lockableComponent;
}
@Override
public Object processInvocation(final InterceptorContext context) throws Exception {
final InvocationContext invocationContext = context.getInvocationContext();
LockableComponent lockableComponent = this.getLockableComponent();
// get the invoked method
Method invokedMethod = invocationContext.getMethod();
if (invokedMethod == null) {
throw MESSAGES.invocationNotApplicableForMethodInvocation(invocationContext);
}
// get the Lock applicable for this method
Lock lock = getLock(lockableComponent, invokedMethod);
// the default access timeout (will be used in the absence of any explicit access timeout value for the invoked method)
AccessTimeoutDetails defaultAccessTimeout = lockableComponent.getDefaultAccessTimeout();
// set to the default values
long time = defaultAccessTimeout.getValue();
TimeUnit unit = defaultAccessTimeout.getTimeUnit();
AccessTimeoutDetails accessTimeoutOnMethod = lockableComponent.getAccessTimeout(invokedMethod);
if (accessTimeoutOnMethod != null) {
if (accessTimeoutOnMethod.getValue() < 0) {
// for any negative value of timeout, we just default to max timeout val and max timeout unit.
// violation of spec! But we don't want to wait indefinitely.
ROOT_LOGGER.debug("Ignoring a negative @AccessTimeout value: " + accessTimeoutOnMethod.getValue() + " and timeout unit: "
+ accessTimeoutOnMethod.getTimeUnit().name() + ". Will default to timeout value: " + defaultAccessTimeout.getValue()
+ " and timeout unit: " + defaultAccessTimeout.getTimeUnit().name());
} else {
// use the explicit access timeout values specified on the method
time = accessTimeoutOnMethod.getValue();
unit = accessTimeoutOnMethod.getTimeUnit();
}
}
// try getting the lock
boolean success = lock.tryLock(time, unit);
if (!success) {
throw MESSAGES.concurrentAccessTimeoutException(invocationContext,time + unit.name());
}
try {
// lock obtained. now proceed!
return invocationContext.proceed();
} finally {
lock.unlock();
}
}
private Lock getLock(LockableComponent lockableComponent, Method method) {
LockType lockType = lockableComponent.getLockType(method);
switch (lockType) {
case READ:
return readWriteLock.readLock();
case WRITE:
return readWriteLock.writeLock();
}
throw MESSAGES.failToObtainLockIllegalType(lockType,method,lockableComponent);
}
}