samoa-api/src/main/java/org/apache/samoa/topology/AbstractEntranceProcessingItem.java

/*
 * 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.samoa.topology;

import org.apache.samoa.core.EntranceProcessor;

/**
 * Helper class for EntranceProcessingItem implementation.
 * 
 * @author Anh Thu Vu
 * 
 */
public abstract class AbstractEntranceProcessingItem implements EntranceProcessingItem {
  private EntranceProcessor processor;
  private String name;
  private Stream outputStream;

  /*
   * Constructor
   */
  public AbstractEntranceProcessingItem() {
    this(null);
  }

  public AbstractEntranceProcessingItem(EntranceProcessor processor) {
    this.processor = processor;
  }

  /*
   * Processor
   */
  /**
   * Set the entrance processor for this EntranceProcessingItem
   * 
   * @param processor
   *          the processor
   */
  protected void setProcessor(EntranceProcessor processor) {
    this.processor = processor;
  }

  /**
   * Get the EntranceProcessor of this EntranceProcessingItem.
   * 
   * @return the EntranceProcessor
   */
  public EntranceProcessor getProcessor() {
    return this.processor;
  }

  /*
   * Name/ID
   */
  /**
   * Set the name (or ID) of this EntranceProcessingItem
   * 
   * @param name
   */
  public void setName(String name) {
    this.name = name;
  }

  /**
   * Get the name (or ID) of this EntranceProcessingItem
   * 
   * @return the name (or ID)
   */
  public String getName() {
    return this.name;
  }

  /*
   * Output Stream
   */
  /**
   * Set the output stream of this EntranceProcessingItem. An EntranceProcessingItem should have only 1 single output
   * stream and should not be re-assigned.
   * 
   * @return this EntranceProcessingItem
   */
  public EntranceProcessingItem setOutputStream(Stream outputStream) {
    if (this.outputStream != null && this.outputStream != outputStream) {
      throw new IllegalStateException("Cannot overwrite output stream of EntranceProcessingItem");
    } else
      this.outputStream = outputStream;
    return this;
  }

  /**
   * Get the output stream of this EntranceProcessingItem.
   * 
   * @return the output stream
   */
  public Stream getOutputStream() {
    return this.outputStream;
  }
}