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 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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
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 * KIND, either express or implied. See the License for the
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package org.apache.olingo.odata2.jpa.processor.api;

import javax.persistence.EntityManager;

import org.apache.olingo.odata2.api.processor.ODataSingleProcessor;
import org.apache.olingo.odata2.jpa.processor.api.access.JPAProcessor;
import org.apache.olingo.odata2.jpa.processor.api.exception.ODataJPAException;
import org.apache.olingo.odata2.jpa.processor.api.factory.ODataJPAFactory;

/**
 * Extend this class and implement an OData JPA processor if the default
 * behavior of OData JPA Processor library has to be overwritten.
 * 
 * The class encapsulates a default processor for handling OData requests and
 * a default builder to build an OData response.
 * 
 */
public abstract class ODataJPAProcessor extends ODataSingleProcessor {

  /**
   * An instance of {@link org.apache.olingo.odata2.jpa.processor.api.ODataJPAContext} object
   */
  protected ODataJPAContext oDataJPAContext;

  /**
   * An instance of {@link org.apache.olingo.odata2.jpa.processor.api.access.JPAProcessor}. The
   * instance is created using {@link org.apache.olingo.odata2.jpa.processor.api.factory.JPAAccessFactory}.
   */
  protected JPAProcessor jpaProcessor;

  /**
   * An instance of {@link org.apache.olingo.odata2.jpa.processor.api.ODataJPAResponseBuilder}. The instance
   * is created using {@link org.apache.olingo.odata2.jpa.processor.api.factory.ODataJPAAccessFactory}.
   */
  protected ODataJPAResponseBuilder responseBuilder;

  public ODataJPAContext getOdataJPAContext() {
    return oDataJPAContext;
  }

  public void setOdataJPAContext(final ODataJPAContext odataJPAContext) {
    oDataJPAContext = odataJPAContext;
  }

  /**
   * Constructor
   * 
   * @param oDataJPAContext
   * non null OData JPA Context object
   */
  public ODataJPAProcessor(final ODataJPAContext oDataJPAContext) {
    if (oDataJPAContext == null) {
      throw new IllegalArgumentException(ODataJPAException.ODATA_JPACTX_NULL);
    }
    this.oDataJPAContext = oDataJPAContext;
    jpaProcessor = ODataJPAFactory.createFactory().getJPAAccessFactory().getJPAProcessor(this.oDataJPAContext);
    responseBuilder =
        ODataJPAFactory.createFactory().getODataJPAAccessFactory().getODataJPAResponseBuilder(this.oDataJPAContext);
  }

  /**
   * The method closes ThreadContext.
   * It is mandatory to call this method to avoid memory leaks.
   * <p/>
   * <b>ATTENTION:</b> If <code>isContainerManaged</code> is set to <code>true</code> at
   * the ODataJPAContext only the cleanup is run but the EntityManager is not closed.
   */
  public void close(boolean forceClose) {
    ODataJPATombstoneContext.cleanup();
    if(!oDataJPAContext.isContainerManaged()) {
      EntityManager em = oDataJPAContext.getEntityManager();
      if (!oDataJPAContext.getODataContext().isInBatchMode() || forceClose) {
        if (em.isOpen()) {
          em.close();
        }
      }
    }
  }

  public void close() {
    close(false);
  }

}