Migrated Java Version of AWS COBOL CardDemo Application for Runtime Execution

CardDemo is an GitHub Logo open-source mainframe COBOL/CICS application developed by Amazon. It showcases modernization techniques for mainframe systems, including migration, testing, and service enablement. The application simulates a credit card management system, enabling organizations to explore modernization strategies and AWS services.

We used the SoftwareMining Translation tool to convert the Amazon-AWS CardDemo's CICS COBOL code into both Java and C# versions.
The Java translation is hosted on the AWS Cloud and is accessible below:

Execute CardDemo in Java

SoftwareMining Automatic Conversion to Java Highlights:

The translated application is pure Java code, without any need for emulation.
There were zero compile-time or runtime errors in the translated code; the primary effort was focused on data migration.
The final application has been successfully deployed on Apache/Tomcat within the AWS Cloud environment.
The C# version is fully native, using C# and HTML, and operates on .NET Standard version 6 or above.

CardDemo: COBOL, Java, and C# Side-by-Side Comparison

This section presents a comparison of a COBOL paragraph and its translations into Java and C#. The sample, taken from the program "COBIL00C", demonstrates how the ACCOUNT-RECORD data structure used in the CICS READ operation is refactored into Object-Relational classes. It also showcases the transformation of CICS/BMS fields into Java Field objects, enabling operations like setFocus(), "setProtected", and more. For more details, refer to our guide on BMS Program Cleanup.

Below is a comparison of a COBOL paragraph with its Java and C# translations from the program "COBIL00C".

READ-ACCTDAT-FILE.

 EXEC CICS READ
   DATASET   (WS-ACCTDAT-FILE)
   INTO      (ACCOUNT-RECORD)
   LENGTH    (LENGTH OF ACCOUNT-RECORD)
   RIDFLD    (ACCT-ID)
   KEYLENGTH (LENGTH OF ACCT-ID)
   UPDATE
   RESP      (WS-RESP-CD)
   RESP2     (WS-REAS-CD)
 END-EXEC

 EVALUATE WS-RESP-CD
  WHEN DFHRESP(NORMAL)
      CONTINUE
  WHEN DFHRESP(NOTFND)
   MOVE 'Y'     TO WS-ERR-FLG
   MOVE 'Account ID NOT found...' TO
                   WS-MESSAGE
  MOVE -1       TO ACTIDINL OF COBIL0AI
   PERFORM SEND-BILLPAY-SCREEN
  WHEN OTHER
   DISPLAY 'RESP:' WS-RESP-CD 'REAS:' WS-REAS-CD
   MOVE 'Y'     TO WS-ERR-FLG
   MOVE 'Unable to lookup Account...' TO
                   WS-MESSAGE
   MOVE -1       TO ACTIDINL OF COBIL0AI
   PERFORM SEND-BILLPAY-SCREEN
 END-EVALUATE.

private void readAcctdatFile () {
  accountRecord.assignKeyLength(
                      accountRecord.getAcctId().lengthOf());
  accountRecord.assignResponseCodeField(
                      variables.getWsRespCd());
  accountRecord.read();
  variables.setReasCd(accountRecord.getResponse2Code());
  
  
  if (variables.getWsRespCd() == CicsCodes.NORMAL) {
    ;
  } 
  else if (variables.getWsRespCd() == CicsCodes.NOTFND) {
    variables.setErrFlg("Y");
    variables.setMessage("Account ID NOT found...");
    cobil0ai.getActidin(). setFocus();
    sendBillpayScreen ();
  } 
  else {
    DisplayHelper.display(this, "RESP:" 
	+ variables.getWsRespCdAsStr() 
	+ "REAS:" + variables.getReasCdAsStr());
    variables.setErrFlg("Y");
    variables.setMessage("Unable to lookup Account...");
    cobil0ai.getActidin().setFocus();
    sendBillpayScreen ();
  }}
  ...

private void void ReadAcctdatFile (){
  accountRecord.AssignKeyLength(
                 accountRecord.AcctId.LengthOf());
  accountRecord.AssignResponseCodeField(
                 variables.WsRespCd);
  accountRecord.Read();
  variables.ReasCd = accountRecord.GetResponse2Code();
  
  
  if (variables.WsRespCd == CicsCodes.NORMAL))
  {
    ;
  } else if (variables.WsRespCd == CicsCodes.NOTFND)
  {
    variables.ErrFlg = "Y";
    variables.Message = "Account ID NOT found...";
    cobil0ai.Actidin.SetFocus();
    SendBillpayScreen ();
  } else
  {
    DisplayHelper.Display(this, "RESP:" + variables.WsRespCd 
	   + "REAS:" + variables.ReasCd);
    variables.ErrFlg = "Y";
    variables.Message = "Unable to lookup Account...";
    cobil0ai.Actidin.SetFocus();
    SendBillpayScreen ();
  }
}

The sample demonstrates the refactoring of the ACCOUNT-RECORD data structure used in CICS READ into Object-Relational classes, and the transformation of CICS/BMS fields into Java Field objects, which support operations like setFocus() and "setProtected".
For more information, see our detailed guide on BMS Program Cleanup.

Additionally, below are snapshots of BMS files translated into JSP/HTML. These represent the design-time views, rendered as HTML files. During runtime, the display will be in JSP for Java-translated applications and in HTML for those converted to C#/.NET.

BMS (mapset) File 'Cocrdup.bms' map 'CCRDUPA'

BMS (mapset) File 'Coactup.bms' map 'CACTUPA'

For a hands-on experience, Test drive the Java translation of CardDemo.

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