org.drools.container.spring.beans.persistence.DroolsSpringJpaManager.java Source code

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Here is the source code for org.drools.container.spring.beans.persistence.DroolsSpringJpaManager.java

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/*
 * Copyright 2010 JBoss Inc
 *
 * 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.drools.container.spring.beans.persistence;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;

import org.drools.persistence.PersistenceContext;
import org.drools.persistence.jpa.JpaPersistenceContext;
import org.drools.runtime.Environment;
import org.drools.runtime.EnvironmentName;
import org.jbpm.persistence.JpaProcessPersistenceContext;
import org.jbpm.persistence.ProcessPersistenceContext;
import org.jbpm.persistence.ProcessPersistenceContextManager;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.orm.jpa.EntityManagerHolder;
import org.springframework.transaction.support.TransactionSynchronizationManager;

public class DroolsSpringJpaManager implements ProcessPersistenceContextManager {

    Logger logger = LoggerFactory.getLogger(getClass());

    Environment env;

    private EntityManagerFactory emf;

    private EntityManager appScopedEntityManager;

    private boolean internalAppScopedEntityManager;

    public DroolsSpringJpaManager(Environment env) {
        this.env = env;
        this.emf = (EntityManagerFactory) env.get(EnvironmentName.ENTITY_MANAGER_FACTORY);

        getApplicationScopedPersistenceContext(); // we create this on initialisation so that we own the EMF reference
                                                  // otherwise Spring will close it after the transaction finishes
    }

    public PersistenceContext getApplicationScopedPersistenceContext() {
        if (this.appScopedEntityManager == null) {
            // Use the App scoped EntityManager if the user has provided it, and it is open.
            this.appScopedEntityManager = (EntityManager) this.env.get(EnvironmentName.APP_SCOPED_ENTITY_MANAGER);
            if (this.appScopedEntityManager != null && !this.appScopedEntityManager.isOpen()) {
                throw new RuntimeException("Provided APP_SCOPED_ENTITY_MANAGER is not open");
            }

            if (this.appScopedEntityManager == null) {
                EntityManagerHolder emHolder = (EntityManagerHolder) TransactionSynchronizationManager
                        .getResource(this.emf);
                if (emHolder == null) {
                    this.appScopedEntityManager = this.emf.createEntityManager();
                    emHolder = new EntityManagerHolder(this.appScopedEntityManager);
                    TransactionSynchronizationManager.bindResource(this.emf, emHolder);
                    internalAppScopedEntityManager = true;
                } else {
                    this.appScopedEntityManager = emHolder.getEntityManager();
                }

                this.env.set(EnvironmentName.APP_SCOPED_ENTITY_MANAGER, emHolder.getEntityManager());
            }
        }
        if (TransactionSynchronizationManager.isActualTransactionActive()) {
            this.appScopedEntityManager.joinTransaction();
        }
        return new JpaPersistenceContext(this.appScopedEntityManager);
    }

    public PersistenceContext getCommandScopedPersistenceContext() {
        return new JpaPersistenceContext((EntityManager) this.env.get(EnvironmentName.CMD_SCOPED_ENTITY_MANAGER));
    }

    public void beginCommandScopedEntityManager() {
        EntityManager cmdScopedEntityManager = (EntityManager) env.get(EnvironmentName.CMD_SCOPED_ENTITY_MANAGER);
        if (cmdScopedEntityManager == null || !cmdScopedEntityManager.isOpen()) {
            EntityManagerHolder emHolder = (EntityManagerHolder) TransactionSynchronizationManager
                    .getResource("cmdEM");
            EntityManager em = null;
            if (emHolder == null) {
                em = this.emf.createEntityManager();
                emHolder = new EntityManagerHolder(em);
                TransactionSynchronizationManager.bindResource("cmdEM", emHolder);
            } else {
                em = emHolder.getEntityManager();
            }
            this.env.set(EnvironmentName.CMD_SCOPED_ENTITY_MANAGER, em);
        }

        this.getCommandScopedPersistenceContext().joinTransaction();
        this.appScopedEntityManager.joinTransaction();

    }

    public void endCommandScopedEntityManager() {
        if (TransactionSynchronizationManager.hasResource("cmdEM")) {
            TransactionSynchronizationManager.unbindResource("cmdEM");
            if (this.env.get(EnvironmentName.CMD_SCOPED_ENTITY_MANAGER) != null) {
                getCommandScopedPersistenceContext().close();
            }

        }
    }

    public void dispose() {
        logger.trace("Disposing DroolsSpringJpaManager");
        if (internalAppScopedEntityManager) {
            //TransactionSynchronizationManager.unbindResource( "appEM" );
            TransactionSynchronizationManager.unbindResource(this.emf);
            if (this.appScopedEntityManager != null && this.appScopedEntityManager.isOpen()) {
                this.appScopedEntityManager.close();
                this.internalAppScopedEntityManager = false;
                this.env.set(EnvironmentName.APP_SCOPED_ENTITY_MANAGER, null);
                this.appScopedEntityManager = null;
            }
            this.endCommandScopedEntityManager();
        }
    }

    public ProcessPersistenceContext getProcessPersistenceContext() {
        return new JpaProcessPersistenceContext(appScopedEntityManager);
    }

}