ActiveMQ example source code file (Supplier.java)

This example ActiveMQ source code file (Supplier.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - ActiveMQ tags/keywords

activemqconnectionfactory, harddrive, item, item, mapmessage, mapmessage, messageconsumer, monitor, quantity, string, string, supplier, supplier, util, vendorordernumber

The ActiveMQ Supplier.java source code

/*
 *  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.
 */
import java.util.Random;

import javax.jms.Connection;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.MapMessage;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageProducer;
import javax.jms.Session;

import org.apache.activemq.ActiveMQConnectionFactory;

/**
 * The Supplier synchronously receives the order from the Vendor and
 * randomly responds with either the number ordered, or some lower
 * quantity. 
 */
public class Supplier implements Runnable {
	private String url;
	private String user;
	private String password;
	private final String ITEM;
	private final String QUEUE;
	
	public Supplier(String item, String queue, String url, String user, String password) {
		this.url = url;
		this.user = user;
		this.password = password;
		this.ITEM = item;
		this.QUEUE = queue;
	}
	
	public void run() {
		ActiveMQConnectionFactory connectionFactory = new ActiveMQConnectionFactory(user, password, url);
		Session session = null;
		Destination orderQueue;
		try {
			Connection connection = connectionFactory.createConnection();

			session = connection.createSession(true, Session.SESSION_TRANSACTED);
			orderQueue = session.createQueue(QUEUE);
			MessageConsumer consumer = session.createConsumer(orderQueue);
			
			connection.start();
			
			while (true) {
				Message message = consumer.receive();
				MessageProducer producer = session.createProducer(message.getJMSReplyTo());
				MapMessage orderMessage;
				if (message instanceof MapMessage) {
					orderMessage = (MapMessage) message;
				} else {
					// End of Stream
					producer.send(session.createMessage());
					session.commit();
					producer.close();
					break;
				}
				
				int quantity = orderMessage.getInt("Quantity");
				System.out.println(ITEM + " Supplier: Vendor ordered " + quantity + " " + orderMessage.getString("Item"));
				
				MapMessage outMessage = session.createMapMessage();
				outMessage.setInt("VendorOrderNumber", orderMessage.getInt("VendorOrderNumber"));
				outMessage.setString("Item", ITEM);
				
				quantity = Math.min(
						orderMessage.getInt("Quantity"),
						new Random().nextInt(orderMessage.getInt("Quantity") * 10));
				outMessage.setInt("Quantity", quantity);
				
				producer.send(outMessage);
				System.out.println(ITEM + " Supplier: Sent " + quantity + " " + ITEM + "(s)");
				session.commit();
				System.out.println(ITEM + " Supplier: committed transaction");
				producer.close();
			}
			connection.close();
		} catch (JMSException e) {
			e.printStackTrace();
		}
	}
	
	public static void main(String[] args) {
		String url = "tcp://localhost:61616";
		String user = null;
		String password = null;
		String item = "HardDrive";
		
		if (args.length >= 1) {
			item = args[0];
		}
		String queue;
		if ("HardDrive".equals(item)) {
			queue = "StorageOrderQueue";
		} else if ("Monitor".equals(item)) {
			queue = "MonitorOrderQueue";
		} else {
			throw new IllegalArgumentException("Item must be either HardDrive or Monitor");
		}
		
		if (args.length >= 2) {
			url = args[1];
		}
		
		if (args.length >= 3) {
			user = args[2];
		}

		if (args.length >= 4) {
			password = args[3];
		}
		
		Supplier s = new Supplier(item, queue, url, user, password);
		
		new Thread(s, "Supplier " + item).start();
	}
}