MessageCollectorMember.java

/**
 * The MIT License
 * Copyright (c) 2014-2016 Ilkka Seppälä
 * <p>
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * <p>
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * <p>
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

package com.iluwatar.databus.members;

import com.iluwatar.databus.DataType;
import com.iluwatar.databus.Member;
import com.iluwatar.databus.data.MessageData;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.logging.Logger;

/**
 * Receiver of Data-Bus events that collects the messages from each {@link MessageData}.
 *
 * @author Paul Campbell (pcampbell@kemitix.net)
 */
public class MessageCollectorMember implements Member {

  private static final Logger LOGGER = Logger.getLogger(MessageCollectorMember.class.getName());

  private final String name;

  private List<String> messages = new ArrayList<>();

  public MessageCollectorMember(String name) {
    this.name = name;
  }

  @Override
  public void accept(final DataType data) {
    if (data instanceof MessageData) {
      handleEvent((MessageData) data);
    }
  }

  private void handleEvent(MessageData data) {
    LOGGER.info(String.format("%s sees message %s", name, data.getMessage()));
    messages.add(data.getMessage());
  }

  public List<String> getMessages() {
    return Collections.unmodifiableList(messages);
  }
}