| /** |
| * 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 com.datatorrent.lib.io.jms; |
| |
| import java.io.Serializable; |
| import java.util.Enumeration; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| import javax.jms.BytesMessage; |
| import javax.jms.JMSException; |
| import javax.jms.MapMessage; |
| import javax.jms.Message; |
| import javax.jms.ObjectMessage; |
| import javax.jms.StreamMessage; |
| import javax.jms.TextMessage; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.datatorrent.api.DefaultOutputPort; |
| |
| /** |
| * An implementation of AbstractJMSInputOperator which emits TextMessage,StreamMessage,BytesMessage,MapMessage |
| * and ObjectMessage on their respective ports. |
| * |
| * @since 2.1.0 |
| */ |
| @org.apache.hadoop.classification.InterfaceStability.Evolving |
| public class JMSObjectInputOperator extends AbstractJMSInputOperator<Object> |
| { |
| public final transient DefaultOutputPort<String> outputString = new DefaultOutputPort<String>(); |
| public final transient DefaultOutputPort<byte[]> outputBytes = new DefaultOutputPort<byte[]>(); |
| public final transient DefaultOutputPort<Map<String, Object>> outputMap = new DefaultOutputPort<Map<String, Object>>(); |
| |
| /** |
| * This implementation converts a TextMessage back to a String, a |
| * ByteMessage back to a byte array, a MapMessage back to a Map, |
| * and an ObjectMessage back to a Serializable object. Returns |
| * the plain Message object in case of an unknown message type. |
| * |
| * @return payload |
| * @throws javax.jms.JMSException |
| */ |
| @Override |
| public Object convert(Message message) throws JMSException |
| { |
| if (message instanceof TextMessage) { |
| return ((TextMessage)message).getText(); |
| } else if (message instanceof StreamMessage) { |
| return ((StreamMessage)message).readString(); |
| } else if (message instanceof BytesMessage) { |
| return extractByteArrayFromMessage((BytesMessage)message); |
| } else if (message instanceof MapMessage) { |
| return extractMapFromMessage((MapMessage)message); |
| } else if (message instanceof ObjectMessage) { |
| return extractSerializableFromMessage((ObjectMessage)message); |
| } else { |
| return message; |
| } |
| } |
| |
| /** |
| * Extract a byte array from the given {@link BytesMessage}. |
| * |
| * @param message the message to convert |
| * @return the resulting byte array |
| * @throws JMSException if thrown by JMS methods |
| */ |
| protected byte[] extractByteArrayFromMessage(BytesMessage message) throws JMSException |
| { |
| byte[] bytes = new byte[(int)message.getBodyLength()]; |
| message.readBytes(bytes); |
| return bytes; |
| } |
| |
| /** |
| * Extract a Map from the given {@link MapMessage}. |
| * |
| * @param message the message to convert |
| * @return the resulting Map |
| * @throws JMSException if thrown by JMS methods |
| */ |
| protected Map<String, Object> extractMapFromMessage(MapMessage message) throws JMSException |
| { |
| Map<String, Object> map = new HashMap<String, Object>(); |
| Enumeration<?> en = message.getMapNames(); |
| while (en.hasMoreElements()) { |
| String key = (String)en.nextElement(); |
| map.put(key, message.getObject(key)); |
| } |
| return map; |
| } |
| |
| /** |
| * Extract a Serializable object from the given {@link ObjectMessage}. |
| * |
| * @param message the message to convert |
| * @return the resulting Serializable object |
| * @throws JMSException if thrown by JMS methods |
| */ |
| protected Serializable extractSerializableFromMessage(ObjectMessage message) throws JMSException |
| { |
| return message.getObject(); |
| } |
| |
| @Override |
| @SuppressWarnings("unchecked") |
| protected void emit(Object payload) |
| { |
| if (outputString.isConnected()) { |
| outputString.emit((String)payload); |
| } else if (outputMap.isConnected()) { |
| outputMap.emit((Map<String, Object>)payload); |
| } else if (outputBytes.isConnected()) { |
| outputBytes.emit((byte[])payload); |
| } else { |
| output.emit(payload); |
| } |
| } |
| |
| @SuppressWarnings("unused") |
| private static final transient Logger logger = LoggerFactory.getLogger(JMSObjectInputOperator.class); |
| |
| } |