PersistenceUnitContainer.java

/**
 * Copyright (C) 2012 Stephan Classen
 * Based on guice-perist (Copyright (C) 2010 Google, 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 com.github.sclassen.guicejpa;

import static com.google.common.base.Preconditions.checkNotNull;

import java.util.HashSet;
import java.util.Set;

/**
 * Container of persistence units. This is a convenience wrapper for multiple
 * persistence units. calling any method of either {@link PersistenceService} or
 * {@link UnitOfWork} will propagate this call to all added persistence units.
 *
 * @author Stephan Classen
 */
class PersistenceUnitContainer implements PersistenceService, UnitOfWork {

  // ---- Members

  /** Collection of all known persistence services. */
  private final Set<PersistenceService> persistenceServices = new HashSet<PersistenceService>();

  /** Collection of all known units of work. */
  private final Set<UnitOfWork> unitsOfWork = new HashSet<UnitOfWork>();


  // ---- Methods

  /**
   * Adds a persistence service and a unit of work to this container.
   *
   * @param ps the persistence service to add. Must not be {@code null}.
   * @param uow the unit of work to add. Must not be {@code null}.
   */
  void add(PersistenceService ps, UnitOfWork uow) {
    checkNotNull(ps);
    checkNotNull(uow);
    persistenceServices.add(ps);
    unitsOfWork.add(uow);
  }

  /**
   * {@inheritDoc}
   */
  @Override
  public synchronized void start() {
    for (PersistenceService ps : persistenceServices) {
      ps.start();
    }
  }

  /**
   * {@inheritDoc}
   */
  @Override
  public synchronized boolean isRunning() {
    for (PersistenceService ps : persistenceServices) {
      if (!ps.isRunning()) {
        return false;
      }
    }
    return true;
  }

  /**
   * {@inheritDoc}
   */
  @Override
  public synchronized void stop() {
    for (PersistenceService ps : persistenceServices) {
      ps.stop();
    }
  }

  /**
   * {@inheritDoc}
   */
  @Override
  public void begin() {
    for (UnitOfWork unitOfWork : unitsOfWork) {
      unitOfWork.begin();
    }
  }

  /**
   * {@inheritDoc}
   */
  @Override
  public boolean isActive() {
    for (UnitOfWork unitOfWork : unitsOfWork) {
      if (!unitOfWork.isActive()) {
        return false;
      }
    }
    return true;
  }

  /**
   * {@inheritDoc}
   */
  @Override
  public void end() {
    for (UnitOfWork unitOfWork : unitsOfWork) {
      unitOfWork.end();
    }

  }

}