Standalone JMS to Mainframe MQ in EBCDIC

Question

I am new to Websphere MQ (IBM z/OS) technologies. We had a requirement to implement a standalone application that uses JMS technology to connect to an MQ server (on IBM z/OS. This is maintained by a different organization for which we have only limited access) and put a message on the queue.

Here are pieces of my code below.

private void sendMessage(String queue, String msg) {
        JmsFactoryFactory ff = JmsFactoryFactory.getInstance(WMQConstants.WMQ_PROVIDER);
        JmsConnectionFactory cf = ff.createConnectionFactory();

        cf.setStringProperty(WMQConstants.WMQ_HOST_NAME, host);
        cf.setIntProperty(WMQConstants.WMQ_PORT, port);
        cf.setStringProperty(WMQConstants.WMQ_CHANNEL, channel);
        cf.setIntProperty(WMQConstants.WMQ_CONNECTION_MODE, WMQConstants.WMQ_CM_CLIENT);
        cf.setStringProperty(WMQConstants.WMQ_QUEUE_MANAGER, queueManagerName);
        cf.setStringProperty(WMQConstants.USERID, user);
        cf.setStringProperty(WMQConstants.PASSWORD, password);

    Connection connection = null;
    Session session = null;
    Destination destination = null;
    MessageProducer producer = null;


        connection = cf.createConnection(user, password);
        session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
        destination = session.createQueue(queue);
        //((MQDestination)destination).setCCSID(37);
        producer = session.createProducer(destination);

        TextMessage message = session.createTextMessage();
        message.setIntProperty(WMQConstants.JMS_IBM_CHARACTER_SET, 37);
        //message.setIntProperty(WMQConstants.JMS_IBM_ENCODING, 785);

        message.setText(msg);
        // Start the connection
        connection.start();

        // And, send the message
        producer.send(message);
}

I was successfully able to connect to the MQ server on the other end and put the messages on the remote server in ASCII format. I was able to consume the message that I have put on the queue from an AIX server.

But since the MQ is running on z/OS and the consumer is also an Mainframe application the message I put appears to be a garbage/unreadable format. After some research I figured out that messages needs to be converted to EBCDIC to be put on z/OS MQ. I expected that this will be taken care of by the IBM MQ libraries.

Please help on how can I put the messages in EBCDIC format.

Answer 1

If possible, use MQ's MQGMO convert option to convert into the local machine's character set. But if you want (or can't) use that mechanism, you can also implement your own character set translation to have full control. For example:

  //---------------------------------------------------
  //Character Translation Table for: IBM500
  private static char[] EBCDIC2ASCII_IBM500 = new char[] {

    0, 1, 2, 3, 156, 9, 134, 127, 151, 141, 142, 11, 12, 13, 14, 15, 
    16, 17, 18, 19, 157, 10, 8, 135, 24, 25, 146, 143, 28, 29, 30, 31, 
    128, 129, 130, 131, 132, 10, 23, 27, 136, 137, 138, 139, 140, 5, 6, 7, 
    144, 145, 22, 147, 148, 149, 150, 4, 152, 153, 154, 155, 20, 21, 158, 26, 
    32, 160, 226, 228, 224, 225, 227, 229, 231, 241, 91, 46, 60, 40, 43, 33, 
    38, 233, 234, 235, 232, 237, 238, 239, 236, 223, 93, 36, 42, 41, 59, 94, 
    45, 47, 194, 196, 192, 193, 195, 197, 199, 209, 166, 44, 37, 95, 62, 63, 
    248, 201, 202, 203, 200, 205, 206, 207, 204, 96, 58, 35, 64, 39, 61, 34, 
    216, 97, 98, 99, 100, 101, 102, 103, 104, 105, 171, 187, 240, 253, 254, 177, 
    176, 106, 107, 108, 109, 110, 111, 112, 113, 114, 170, 186, 230, 184, 198, 164, 
    181, 126, 115, 116, 117, 118, 119, 120, 121, 122, 161, 191, 208, 221, 222, 174, 
    162, 163, 165, 183, 169, 167, 182, 188, 189, 190, 172, 124, 175, 168, 180, 215, 
    123, 65, 66, 67, 68, 69, 70, 71, 72, 73, 173, 244, 246, 242, 243, 245, 
    125, 74, 75, 76, 77, 78, 79, 80, 81, 82, 185, 251, 252, 249, 250, 255, 
    92, 247, 83, 84, 85, 86, 87, 88, 89, 90, 178, 212, 214, 210, 211, 213, 
    48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 179, 219, 220, 217, 218, 159
  };

  private static char[] ASCII2EBCDIC_IBM500 = new char[] {
      0, 1, 2, 3, 55, 45, 46, 47, 22, 5, 37, 11, 12, 13, 14, 15, 
      16, 17, 18, 19, 60, 61, 50, 38, 24, 25, 63, 39, 28, 29, 30, 31, 
      64, 79, 127, 123, 91, 108, 80, 125, 77, 93, 92, 78, 107, 96, 75, 97, 
      240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 122, 94, 76, 126, 110, 111, 
      124, 193, 194, 195, 196, 197, 198, 199, 200, 201, 209, 210, 211, 212, 213, 214, 
      215, 216, 217, 226, 227, 228, 229, 230, 231, 232, 233, 74, 224, 90, 95, 109, 
      121, 129, 130, 131, 132, 133, 134, 135, 136, 137, 145, 146, 147, 148, 149, 150, 
      151, 152, 153, 162, 163, 164, 165, 166, 167, 168, 169, 192, 187, 208, 161, 7, 
      32, 33, 34, 35, 36, 0, 6, 23, 40, 41, 42, 43, 44, 9, 10, 27, 
      48, 49, 26, 51, 52, 53, 54, 8, 56, 57, 58, 59, 4, 20, 62, 255, 
      65, 170, 176, 177, 159, 178, 106, 181, 189, 180, 154, 138, 186, 202, 175, 188, 
      144, 143, 234, 250, 190, 160, 182, 179, 157, 218, 155, 139, 183, 184, 185, 171, 
      100, 101, 98, 102, 99, 103, 158, 104, 116, 113, 114, 115, 120, 117, 118, 119, 
      172, 105, 237, 238, 235, 239, 236, 191, 128, 253, 254, 251, 252, 173, 174, 89, 
      68, 69, 66, 70, 67, 71, 156, 72, 84, 81, 82, 83, 88, 85, 86, 87, 
      140, 73, 205, 206, 203, 207, 204, 225, 112, 221, 222, 219, 220, 141, 142, 223
      };

  public static void main(String[] args)
  {
    String ebcdic = "" + (char)0xC1 + (char)0xC2 + (char)0xC3;
    System.err.println("ebcdic: " + ebcdic);

    String ascii = "";
    for( char c: ebcdic.toCharArray() ) {

      ascii += EBCDIC2ASCII_IBM500[c];
    }
    System.err.println("ascii:  " + ascii);

    ebcdic="";
    for( char c: ascii.toCharArray() ) {

      ebcdic += ASCII2EBCDIC_IBM500[c];
    }
    System.err.println("ebcdic: " + ebcdic);
  }

And here's the code to create these tables:

public static void createTranslationTable(Charset charset)
 {
   System.out.println();
   System.out.println("// ---------------------------------------------------" );
   System.out.println("// Character Translation Tables for: " + charset.name() );

   byte[] b = new byte[256];
   for( int i=0;i<256;i++ ) b[i] = (byte)i;

   String s = "";
   try {
     s = new String(b,charset.name());
   }
   catch (UnsupportedEncodingException e) {
     e.printStackTrace();
   }

   int[] inverse = new int[256];

   System.out.println("unsigned char EBCDIC2ASCII_" + charset.name() + "[256] = {");
   for( int i=0;i<256;i++ ) {

     int c = s.charAt(i); // %256;
     if( c>255 ) c=i;
     inverse[c] = i;

     System.out.print( c + (i<255?", ":"") );
     if( i%16==15 ) System.out.println();
   }
   System.out.println("};");

   System.out.println("unsigned char ASCII2EBCDIC_" + charset.name() + "[256] = {");

   for( int i=0;i<256;i++ ) {

     int c = inverse[i]; // %256;
     System.out.print( c + (i<255?", ":"") );
     if( i%16==15 ) System.out.println();
   }

   System.out.println("};");
 }

And you could use it like this:

 createTranslationTable( Charset.forName("CP037") );

Answer 2

More importantly, if your receiver is not a Java client, you need to disable the JMS header as follows:

destination = session.createQueue("queue:///" + queue + "?targetClient=1")

or by invoking the Native MQ implementation :

((MQDestination)destination).setMessageBodyStyle(WMQConstants.WMQ_MESSAGE_BODY_MQ)

See:

https://www-01.ibm.com/support/knowledgecenter/SSFKSJ_8.0.0/com.ibm.mq.dev.doc/q032120_.htm

https://www-01.ibm.com/support/knowledgecenter/SSFKSJ_8.0.0/com.ibm.mq.dev.doc/q032140_.htm?lang=en

http://www-01.ibm.com/support/knowledgecenter/SSFKSJ_7.0.1/com.ibm.mq.csqzaw.doc/jm10910_.htm

Answer 3

To store your message in a non-standard-encoding you will have to use BytesMessage instead of TextMessage. This might work (untested!):

byte[] messageBytes = msg.getBytes("IBM037");
BytesMessage message = session.createBytesMessage();
message.writeBytes(messageBytes);

But it would be preferable to have the given message-encoding respected at the consuming side - that's why you put it there.

Answer 4

You are doing this wrong:

message.setIntProperty(WMQConstants.JMS_IBM_CHARACTER_SET, 37);

You need to declare the character set that you are putting on the queue. Since that looks like Java, I'm assuming it is a UTF-16 string. Declare it as 1208, not 37.

On the other end, if they want it in EBCDIC, they will do a GET-With-Convert, declaring that they want to receive it in IBM 37/1140 and MQ will invoke Unicode Conversion Services for z/OS and make it happen.