ISO Message: Packing and Un-Packing

Dear Reader,
Here I am writing about how to pack and unpack ISO messages for banking transactions.
For basic necessary stuffs please read my earlier written blog and then come here, link is below:
http://deepakmodi2006.blogspot.in/2012/04/iso-8583-standard-in-java-for-financial.html

jPOS is a Java platform-based, ISO-8583 based financial transaction library/framework that can be 
customized and extended in order to implement financial interchanges.

So first thing to do is download JPOS libraries from its website.
Following Jars are required for the same. Please see the picture below.



For packing and unpacking an ISO message I have written four programs:
    basic.xml
    genericpackager.dtd
    BuildISOMessage.java
    ParseISOMessage.java
    Output of program..
















-------------------------------------------
package dmodi;
import java.io.IOException;
import org.jpos.iso.ISOException;
import org.jpos.iso.ISOMsg;
import org.jpos.iso.packager.GenericPackager;

public class BuildISOMessage {
    public static void main(String[] args) throws IOException, ISOException {
        
        //Create Packager based on XML that contain DE type
        GenericPackager packager = new GenericPackager("basic.xml");

        // Create ISO Message
        ISOMsg isoMsg = new ISOMsg();
        isoMsg.setPackager(packager);
        isoMsg.setMTI("0200");
        isoMsg.set(3, "201234");
        isoMsg.set(4, "10000");
        isoMsg.set(7, "110722180");
        isoMsg.set(11, "123456");
        isoMsg.set(32, "100005");
        isoMsg.set(44, "A5DFGR");
        isoMsg.set(105, "ABCDEFGHIJ 1234567890");

        // print the DE list
        logISOMsg(isoMsg);

        // Get and print the output result
        byte[] data = isoMsg.pack();
        String dataString=new String(data);
        System.out.println("Packed ISO Message : " +dataString);
        
        ParseISOMessage parse=new ParseISOMessage();
        parse.setData(dataString);
        parse.parseIsoMessage();
    }

    private static void logISOMsg(ISOMsg msg) {
        System.out.println("----ISO MESSAGE to Pack-----");
        try {
            System.out.println("  MTI : " + msg.getMTI());
            for (int i = 1; i <= msg.getMaxField(); i++) {
                if (msg.hasField(i)) {
                    System.out.println("    Field-" + i + " : " + msg.getString(i));
                }
            }
        } catch (ISOException e) {
            e.printStackTrace();
        } finally {
            System.out.println("--------------------");
        }
    }
}
-------------------------------------------
//ParseISOMessage.java
package dmodi;
import java.io.IOException;
import org.jpos.iso.ISOException;
import org.jpos.iso.ISOMsg;
import org.jpos.iso.packager.GenericPackager;

public class ParseISOMessage {
    String data="";
    public void parseIsoMessage() throws IOException, ISOException {
        // Create Packager based on XML that contain DE type
        GenericPackager packager = new GenericPackager("basic.xml");
        System.out.println("Data to unpack : " + data);

        // Create ISO Message
        ISOMsg isoMsg = new ISOMsg();
        isoMsg.setPackager(packager);
        isoMsg.unpack(data.getBytes());

        // print the DE list
        logISOMsg(isoMsg);
    }

    private static void logISOMsg(ISOMsg msg) {
        System.out.println("----Unpacked ISO MESSAGE-----");
        try {
            System.out.println("  MTI : " + msg.getMTI());
            for (int i = 1; i <= msg.getMaxField(); i++) {
                if (msg.hasField(i)) {
                    System.out.println("    Field-" + i + " : " + msg.getString(i));
                }
            }
        } catch (ISOException e) {
            e.printStackTrace();
        } finally {
            System.out.println("--------------------");
        }
    }
    public void setData(String strData){
        data=strData;
    }
}
-------------------------------------------
//basic.xml
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE isopackager SYSTEM "genericpackager.dtd">
<isopackager>
  <isofield
      id="0"
      length="4"
      name="MESSAGE TYPE INDICATOR"
      class="org.jpos.iso.IFA_NUMERIC"/>
  <isofield
      id="1"
      length="64"
      name="BIT MAP"
      class="org.jpos.iso.IFA_BITMAP"/>
  <isofield
      id="3"
      length="6"
      name="PROCESSING CODE"
      class="org.jpos.iso.IFA_NUMERIC"/>
  <isofield
      id="4"
      length="12"
      name="AMOUNT, TRANSACTION"
      class="org.jpos.iso.IFA_NUMERIC"/>
  <isofield
      id="7"
      length="10"
      name="TRANSMISSION DATE AND TIME"
      class="org.jpos.iso.IFA_NUMERIC"/>
  <isofield
      id="11"
      length="6"
      name="SYSTEM TRACE AUDIT NUMBER"
      class="org.jpos.iso.IFA_NUMERIC"/>
  <isofield
      id="32"
      length="6"
      name="Acquirer Id"
      class="org.jpos.iso.IFA_NUMERIC"/>
  <isofield
      id="44"
      length="25"
      name="ADITIONAL RESPONSE DATA"
      class="org.jpos.iso.IFA_LLCHAR"/>
  <isofield
      id="105"
      length="999"
      name="RESERVED ISO USE"
      class="org.jpos.iso.IFA_LLLCHAR"/>
</isopackager>
-------------------------------------------
//genericpackager.dtd
<?xml version="1.0" encoding="UTF-8"?>
<!ELEMENT isopackager (isofield+,isofieldpackager*)*>
<!ATTLIST isopackager maxValidField CDATA        #IMPLIED>
<!ATTLIST isopackager bitmapField   CDATA        #IMPLIED>
<!ATTLIST isopackager firstField    CDATA        #IMPLIED>
<!ATTLIST isopackager emitBitmap    (true|false) #IMPLIED>
<!ATTLIST isopackager headerLength  CDATA        #IMPLIED>

<!-- isofield -->
<!ELEMENT isofield (#PCDATA)>
<!ATTLIST isofield id     CDATA        #REQUIRED>
<!ATTLIST isofield length CDATA        #REQUIRED>
<!ATTLIST isofield name   CDATA        #REQUIRED>
<!ATTLIST isofield class  NMTOKEN      #REQUIRED>
<!ATTLIST isofield token  CDATA        #IMPLIED>
<!ATTLIST isofield pad    (true|false) #IMPLIED>

<!-- isofieldpackager -->
<!ELEMENT isofieldpackager (isofield+,isofieldpackager*)*>
<!ATTLIST isofieldpackager id       CDATA        #REQUIRED>
<!ATTLIST isofieldpackager name     CDATA        #REQUIRED>
<!ATTLIST isofieldpackager length   CDATA        #REQUIRED>
<!ATTLIST isofieldpackager class    NMTOKEN      #REQUIRED>
<!ATTLIST isofieldpackager token    CDATA        #IMPLIED>
<!ATTLIST isofieldpackager pad      (true|false) #IMPLIED>
<!ATTLIST isofieldpackager packager NMTOKEN      #REQUIRED>
<!ATTLIST isofieldpackager emitBitmap (true|false) #IMPLIED>
<!ATTLIST isofieldpackager maxValidField CDATA        #IMPLIED>
<!ATTLIST isofieldpackager bitmapField CDATA        #IMPLIED>
<!ATTLIST isofieldpackager firstField  CDATA        #IMPLIED>
<!ATTLIST isofieldpackager headerLength  CDATA        #IMPLIED>
-------------------------------------------

Output:

----ISO MESSAGE to Pack-----
  MTI : 0200
    Field-3 : 201234
    Field-4 : 10000
    Field-7 : 110722180
    Field-11 : 123456
    Field-32 : 100005
    Field-44 : A5DFGR
    Field-105 : ABCDEFGHIJ 1234567890
--------------------
Packed ISO Message : 0200B2200001001000000000000000800000201234000000010000011072218012345610000506A5DFGR021ABCDEFGHIJ 1234567890
Data to unpack : 0200B2200001001000000000000000800000201234000000010000011072218012345610000506A5DFGR021ABCDEFGHIJ 1234567890
----Unpacked ISO MESSAGE-----
  MTI : 0200
    Field-3 : 201234
    Field-4 : 000000010000
    Field-7 : 0110722180
    Field-11 : 123456
    Field-32 : 100005
    Field-44 : A5DFGR
    Field-105 : ABCDEFGHIJ 1234567890
--------------------

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