EntityTransactionAspect.java

/**
 * Copyright 2010 CosmoCode GmbH
 *
 * 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 de.cosmocode.palava.jpa.aspectj;

import com.google.common.base.Preconditions;
import com.google.inject.Inject;
import com.google.inject.Provider;
import de.cosmocode.commons.Throwables;
import de.cosmocode.palava.core.aop.PalavaAspect;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.SuppressAjWarnings;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.persistence.EntityManager;
import javax.persistence.EntityTransaction;
import javax.persistence.PersistenceException;

/**
 * Aspect for methods annotated with {@link de.cosmocode.palava.jpa.Transactional}.
 */
@Aspect
public final class EntityTransactionAspect extends PalavaAspect {

    private static final Logger LOG = LoggerFactory.getLogger(EntityTransactionAspect.class);

    private Provider<EntityManager> currentManager;
    
    @Inject
    public void setProvider(Provider<EntityManager> manager) {
        this.currentManager = Preconditions.checkNotNull(manager, "Manager");
    }

    // CHECKSTYLE:OFF
    @Around("execution(@de.cosmocode.palava.jpa.Transactional * *.*(..))")
    public Object transactional(ProceedingJoinPoint point) {
        checkInjected();

        final EntityManager manager = currentManager.get();
        LOG.trace("Retrieved entitymanager {}", manager);
        final EntityTransaction tx = manager.getTransaction();
        LOG.trace("Using transaction {}", tx);
        
        final boolean local = !tx.isActive();
        
        if (local) {
            LOG.debug("Beginning automatic transaction {}", tx);
            tx.begin();
        } else {
            LOG.trace("Transaction {} already active", tx);
        }
        
        final Object returnValue;
        
        try {
            returnValue = point.proceed();
        } catch (Throwable e) {
            try {
                if (local && (tx.isActive() || tx.getRollbackOnly())) {
                    LOG.debug("Rolling back local/active transaction {}", tx);
                    tx.rollback();
                } else if (!tx.getRollbackOnly()) {
                    LOG.debug("Setting transaction {} as rollback only", tx);
                    tx.setRollbackOnly();
                }
            } catch (PersistenceException inner) {
                LOG.error("Rollback failed", inner);
            } finally {
                throw Throwables.sneakyThrow(e);
            }
        }

        if (local && tx.isActive()) {
            if (tx.getRollbackOnly()) {
                LOG.debug("Rolling back marked transaction {}", tx);
                tx.rollback();
            } else {
                try {
                    tx.commit();
                    LOG.debug("Committed automatic transaction {}", tx);
                } catch (PersistenceException e) {
                    if (tx.isActive()) {
                        try {
                            LOG.debug("Rolling back transaction {}", tx);
                            tx.rollback();
                        } catch (PersistenceException inner) {
                            LOG.error("Rollback failed", inner);
                        }
                    }
                    throw e;
                }
            }
        } else {
            LOG.trace("Not committing non-local transaction {}", tx);
        }
        
        return returnValue;
    }
    // CHECKSTYLE:ON

}