/*
 * � 2001-2009, Progress Software Corporation and/or its subsidiaries or affiliates.  All rights reserved.
 *
 * Licensed 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.
 
Sample Application

Writing a Basic JMS Application with Point-to-Point Queues,
using:
    - Synchronous Request/Reply
    - javax.jms.QueueRequestor class
    - JMSReplyTo Header

When this program runs, it waits for messages on the queue,
"SampleQ1" (by default).
When that message arrives, a response based on the request
is sent back to the "Requestor" specified in the JMSReplyTo header.

This sample replies with a simple text manipulation of the request;
the text is either folded to all UPPERCASE or all lowercase.

Usage:
  java Replier -b <broker:port> -u <username> -p <password> -qr <queue> -m <code>
      -b broker:port points to your message broker
                     Default: tcp://localhost:61616
      -u username    must be unique (but is not checked)
                     Default: SampleReplier
      -p password    password for user (not checked)
                     Default: password
      -qr queue      name of queue for receiving requests
                     Default:  Q1
      -m mode        replier mode (uppercase, or lowercase)
                     Default: uppercase

Suggested demonstration:
  - In a console window with the environment set,
    start a copy of the Replier. For example:
       java Replier -u SampleQReplier
  - In another console window, start a Requestor.
    For example:
       java Requestor -u SampleQRequestor
  - Enter text in the Requestor window then press Enter.
    The Replier responds with the message in all uppercase characters.
  - Start other Requestors with different user names to see that
    replies are not broadcast to all users. For example:
       java Requestor -u SampleRequestorFoo

  - Start other Repliers.
  - See that only one replier is receiving messages,(as it should).
  - See the Requestor only receives one response.
       java Replier -u toLower -m lowercase

 */
import org.apache.activemq.*;


public class Replier
    implements javax.jms.MessageListener
{
    private static final String DEFAULT_BROKER_NAME = "tcp://localhost:61616";
    private static final String DEFAULT_USER_NAME = "SampleReplier";
    private static final String DEFAULT_PASSWORD = "password";
    private static final String DEFAULT_QUEUE = "Q1";
    private static final String DEFAULT_MODE = "uppercase";
    private static final int UPPERCASE = 0;
    private static final int LOWERCASE = 1;

    private javax.jms.Connection connect = null;
    private javax.jms.Session session = null;
    private javax.jms.MessageProducer replier = null;

    private int imode = UPPERCASE;

    /** Create JMS client for sending and receiving messages. */
    private void start ( String broker, String username, String password, String rQueue, String mode)
    {
        // Set the operation mode
        imode = (mode.equals("uppercase")) ? UPPERCASE : LOWERCASE;

        // Create a connection.
        try
        {
            javax.jms.ConnectionFactory factory;
            factory = new ActiveMQConnectionFactory(username, password, broker);
            connect = factory.createConnection (username, password);
            session = connect.createSession(true, javax.jms.Session.AUTO_ACKNOWLEDGE);
        }
        catch (javax.jms.JMSException jmse)
        {
            System.err.println("error: Cannot connect to Broker - " + broker);
            jmse.printStackTrace();
            System.exit(1);
        }

        // Create Receivers to application queues as well as a Sender
        // to use for JMS replies.
        try
        {
            javax.jms.Queue queue = session.createQueue (rQueue);
            javax.jms.MessageConsumer receiver = session.createConsumer(queue);
            receiver.setMessageListener(this);
            replier = session.createProducer(null);  // Queue will be set for each reply
            // Now that all setup is complete, start the Connection
            connect.start();
        }
        catch (javax.jms.JMSException jmse)
        {
            jmse.printStackTrace();
            exit();
        }

        try
        {
            // Read standard input waiting for "EXIT" command.
            java.io.BufferedReader stdin =
                new java.io.BufferedReader( new java.io.InputStreamReader( System.in ) );
            while ( true )
            {
                   System.out.println ("\nReplier application:\n"
			            					+ "============================\n"
			            					+ "The application user " + username + " connects to the broker at " + DEFAULT_BROKER_NAME + ".\n"
											+ "The application gets requests with JMSReplyTo set on the " + DEFAULT_QUEUE + " queue."
											+ "The message is transformed to all uppercase or all lowercase, and then returned to the requestor."
			                                + "The Requestor application displays the result.\n\n"
			                                + "Enter EXIT or press Ctrl+C to close the Replier.\n");
                String s = stdin.readLine();
                if ( s == null || s.equalsIgnoreCase("EXIT"))
                {
                    System.out.println ("\nStopping Replier. Please wait..\n>");
                    exit();
                }
           }
        }
        catch ( java.io.IOException ioe )
        {
            ioe.printStackTrace();
        }
    }

    /**
     * Handle the message.
     * (as specified in the javax.jms.MessageListener interface).
     *
     * IMPORTANT NOTES:
     * (1)We must follow the design paradigm for JMS
     *    synchronous requests.  That is, we must:
     *     - get the message
     *     - look for the header specifying JMSReplyTo
     *     - send a reply to the queue specified there.
     *    Failing to follow these steps might leave the originator
     *    of the request waiting forever.
     * (2)Unlike the 'Talk' sample and others using an asynchronous
     *    message listener, it is possible here to use ONLY
     *    ONE SESSION because the messages being sent are sent from
     *    the same thread of control handling message delivery. For
     *    more information see the JMS spec v1.0.2 section 4.4.6.
     *
     * OPTIONAL BEHAVIOR: The following actions taken by the
     * message handler represent good programming style, but are
     * not required by the design paradigm for JMS requests.
     *   - set the JMSCorrelationID (tying the response back to
     *     the original request.
     *   - use transacted session "commit" so receipt of request
     *     won't happen without the reply being sent.
     *
     */
    public void onMessage( javax.jms.Message aMessage)
    {
        try
        {
            // Cast the message as a text message.
            javax.jms.TextMessage textMessage = (javax.jms.TextMessage) aMessage;

            // This handler reads a single String from the
            // message and prints it to the standard output.
            try
            {
                String string = textMessage.getText();
                System.out.println( "[Request] " + string );

                // Check for a ReplyTo Queue
                javax.jms.Queue replyQueue = (javax.jms.Queue) aMessage.getJMSReplyTo();
                if (replyQueue != null)
                {
                    // Send the modified message back.
                    javax.jms.TextMessage reply =  session.createTextMessage();
                    if (imode == UPPERCASE)
                        reply.setText("Uppercasing-" + string.toUpperCase());
                    else
                        reply.setText("Lowercasing-" + string.toLowerCase());
                    reply.setJMSCorrelationID(aMessage.getJMSMessageID());
                    replier.send (replyQueue, reply);
                    session.commit();
                }
            }
            catch (javax.jms.JMSException jmse)
            {
                jmse.printStackTrace();
            }
        }
        catch (java.lang.RuntimeException rte)
        {
            rte.printStackTrace();
        }
    }

    /** Cleanup resources cleanly and exit. */
    private void exit()
    {
        try
        {
            connect.close();
        }
        catch (javax.jms.JMSException jmse)
        {
            jmse.printStackTrace();
        }

        System.exit(0);
    }

    //
    // NOTE: the remainder of this sample deals with reading arguments
    // and does not utilize any JMS classes or code.
    //

    /** Main program entry point. */
    public static void main(String argv[]) {

        // Values to be read from parameters
        String broker    = DEFAULT_BROKER_NAME;
        String username  = DEFAULT_USER_NAME;
        String password  = DEFAULT_PASSWORD;
        String queue     = DEFAULT_QUEUE;
        String mode      = DEFAULT_MODE;

        // Check parameters
        for (int i = 0; i < argv.length; i++) {
            String arg = argv[i];


            if (arg.equals("-b")) {
                if (i == argv.length - 1 || argv[i+1].startsWith("-")) {
                    System.err.println("error: missing broker name:port");
                    System.exit(1);
                }
                broker = argv[++i];
                continue;
            }

            if (arg.equals("-u")) {
                if (i == argv.length - 1 || argv[i+1].startsWith("-")) {
                    System.err.println("error: missing user name");
                    System.exit(1);
                }
                username = argv[++i];
                continue;
            }

            if (arg.equals("-p")) {
                if (i == argv.length - 1 || argv[i+1].startsWith("-")) {
                    System.err.println("error: missing password");
                    System.exit(1);
                }
                password = argv[++i];
                continue;
            }

            if (arg.equals("-qr")) {
                if (i == argv.length - 1 || argv[i+1].startsWith("-")) {
                    System.err.println("error: missing queue");
                    System.exit(1);
                }
                queue = argv[++i];
                continue;
            }

            if (arg.equals("-m")) {
                if (i == argv.length - 1 || argv[i+1].startsWith("-")) {
                    System.err.println("error: missing mode");
                    System.exit(1);
                }
                mode = argv[++i];
                if (!(mode.equals("uppercase") || mode.equals("lowercase"))) {
                    System.err.println("error: mode must be 'uppercase' or 'lowercase'");
                    System.exit(1);
                }
                continue;
            }

            if (arg.equals("-h")) {
                printUsage();
                System.exit(1);
            }

            // Invalid argument
            System.err.println ("error: unexpected argument: "+arg);
            printUsage();
            System.exit(1);
        }

        // Start the JMS client.
        Replier replier = new Replier ();
        replier.start (broker, username, password, queue, mode);
    }

    /** Prints the usage. */
    private static void printUsage() {

        StringBuffer use = new StringBuffer();
        use.append("usage: java Replier (options) ...\n\n");
        use.append("options:\n");
        use.append("  -b name:port Specify name:port of broker.\n");
        use.append("               Default broker: "+DEFAULT_BROKER_NAME+"\n");
        use.append("  -u name      Specify unique user name.\n");
        use.append("               Default broker: "+DEFAULT_USER_NAME+"\n");
        use.append("  -p password  Specify password for user.\n");
        use.append("               Default password: "+DEFAULT_PASSWORD+"\n");
        use.append("  -m mode      Replier operating mode - uppercase or lowercase.\n");
        use.append("               Default mode: "+DEFAULT_MODE+"\n");
        use.append("  -qr queue    Specify name of queue for receiving.\n");
        use.append("               Default queue: "+DEFAULT_QUEUE+"\n");
        use.append("  -h           This help screen.\n");
        System.err.println (use);
    }

}
