/*************************************************************************
 * Copyright 2009-2014 Eucalyptus Systems, Inc.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 3 of the License.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see http://www.gnu.org/licenses/.
 *
 * Please contact Eucalyptus Systems, Inc., 6755 Hollister Ave., Goleta
 * CA 93117, USA or visit http://www.eucalyptus.com/licenses/ if you need
 * additional information or have any questions.
 ************************************************************************/
package com.eucalyptus.entities;

import javax.persistence.EntityTransaction;

/**
 * AutoCloseable transaction suitable for use in try with resources:
 *
 * <pre>
 * try ( TransactionResource transaction = ... ) {
 *   ...
 *   transaction.commit( );
 * }
 * </pre>
 *
 * If not committed the transaction will rollback.
 */
public class TransactionResource implements AutoCloseable, EntityTransaction {

  private final EntityTransaction entityTransaction;

  TransactionResource( final EntityTransaction entityTransaction ) {
    this.entityTransaction = entityTransaction;
  }

  @Override
  public void close( ) {
    if ( isActive( ) ) rollback( );
  }

  @Override
  public void begin( ) {
    entityTransaction.begin( );
  }

  @Override
  public void commit( ) {
    entityTransaction.commit( );
  }

  @Override
  public void rollback( ) {
    entityTransaction.rollback( );
  }

  @Override
  public void setRollbackOnly( ) {
    entityTransaction.setRollbackOnly( );
  }

  @Override
  public boolean getRollbackOnly( ) {
    return entityTransaction.getRollbackOnly( );
  }

  @Override
  public boolean isActive( ) {
    return entityTransaction.isActive( );
  }
}