content: /**
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * 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
   * "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.apache.apex.malhar.contrib.couchdb;
  
  import javax.validation.constraints.NotNull;
  
  import org.apache.apex.malhar.lib.util.PojoUtils;
  import org.apache.apex.malhar.lib.util.PojoUtils.Getter;
  import org.apache.hadoop.classification.InterfaceStability.Evolving;
  
  /**
   * Implementation of {@link AbstractCouchDBOutputOperator} that saves a POJO in the couch database. <br/>
   * <p>
   * @displayName CouchDb Output Operator
   * @category Output
   * @tags database, nosql, pojo, couchdb
   * @since 0.3.5
   */
  @Evolving
  public class CouchDBPOJOOutputOperator extends AbstractCouchDBOutputOperator<Object>
  {
    private static final long serialVersionUID = 201506181121L;
    private transient Getter<Object, String> getterDocId;
  
    @NotNull
    private String expressionForDocId;
  
    /**
     * Gets the getter expression for the document Id.
     * @return The document Id.
     */
    public String getExpressionForDocId()
    {
      return expressionForDocId;
    }
  
    /**
     * An Expression to extract value of document Id from an input POJO.
     * @param expressionForDocId The getter expression for the document Id.
     */
    public void setExpressionForDocId(String expressionForDocId)
    {
      this.expressionForDocId = expressionForDocId;
    }
  
    @Override
    public String getDocumentId(Object tuple)
    {
      if (getterDocId == null) {
        getterDocId = PojoUtils.createGetter(tuple.getClass(), expressionForDocId, String.class);
      }
      String docId = getterDocId.get(tuple);
      return docId;
    }
  
  }
  