Introduction to the IBM Application Development Tools on z/OS and OS/390

Chapter 13. Scenario 2: Using Debug Tool 391

13.2 Walkthrough of the batch Trader application

The batch Trader application is used to maintain stock portfolios held by

individuals. You execute a batch job that processes a day’s worth of trading

activity, which:

򐂰 Lists portfolios and their value

򐂰 Buys shares of a company’s stock

򐂰 Sells shares of a company’s stock

13.2.1 The Trader batch job

The batch job that executes the Trader application is shown in Example 13-1.

Example 13-1 JCL to run the batch Trader application

//DAVINR2R JOB (123,A,TESTING,'WILFRIED'),'ENHANCE',

// CLASS=A,MSGCLASS=H,MSGLEVEL=(1,1),

// REGION=32M,NOTIFY=&SYSUID

//********************************************************************

//* LICENSED MATERIALS - PROPERTY OF IBM *

//* 5655-ADS (C) COPYRIGHT IBM CORP. 2000 *

//* ALL RIGHTS RESERVED *

//********************************************************************

//GO EXEC PGM=TRADERB

//STEPLIB DD DISP=SHR,DSN=DAVINR2.DEMOS.PDPAK.LOAD

// DD DISP=SHR,DSN=CEE210.SCEERUN

//SYSPRINT DD SYSOUT=*

//SYSABEND DD SYSOUT=*

//COMPFILE DD DISP=SHR,DSN=DAVINR2.DEMOS.PDPAK.COMPFILE

//CUSTFILE DD DISP=SHR,DSN=DAVINR2.DEMOS.PDPAK.CUSTFILE

//TRANSACT DD DISP=SHR,DSN=DAVINR2.DEMOS.PDPAK.SAMPLES(TRANFILE)

//REPOUT DD SYSOUT=*

//TRANREP DD SYSOUT=*

//*

The job invokes program TRADERB, which reads a sequential file (TRANSACT)

to obtain the day’s transactions. The program processes each of the records in

this file. At the same time, the program reads the company file (COMPFILE) and

reads and updates the customer file (CUSTFILE).

Note: This example was designed to demonstrate the capabilities of the

Problem Determination Tools. Therefore, a minimal amount of code was

developed. This application does not represent real-world securities

processing.

392 IBM Application Development Tools for z/OS and OS/390

After the program processes the input file, it generates two output reports:

REPOUT, which contains a list of all customer portfolios and TRANREP, which

contains a detailed list of the transaction activity and processing status.

13.2.2 The transaction file

The transaction file is an 80-byte, sequential file that is input to the Trader

application. It can contain three types of requests:

򐂰 List shares

򐂰 Buy shares

򐂰 Sell shares

Example 13-2, shows typical records in the transaction file.

Example 13-2 Batch Trader application transaction file

----+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----

12345RB_DEMO .IBM BUY_SELL 00301

12345RB_DEMO .Veck_Transport BUY_SELL 00251

12345RB_DEMO SHARE_vaLUE

The record layout for the transaction file is shown in Table 13-2.

Table 13-2 Transaction file record layout

After the program, TRADERB, reads each record, it examines the

TR-REQUEST-TYPE field to determine the type of processing to perform.

Column Description Field name

1-5 Account number TR-ACCOUNT-NUMBER

6-35 Customer name TR-CUSTOMER-NAME

36 Dot FILLER

37-51 Company name TR-COMPANY-NAME

52-71 Request type TR-REQUEST-TYPE

72-75 Number of shares (for Buy

or Sell requests)

TR-NO-OF-SHARES

76 Transaction type (for Buy

or Sell requests)

TR-SUBTYPE

77-80 Blank FILLER

Chapter 13. Scenario 2: Using Debug Tool 393

13.2.3 Listing shares

If the field, TR-REQUEST-TYPE, contains the value, SHARE_vaLUE, the program uses

the value in the TR-CUSTOMER-NAME field to print a report that lists the shares held

by that customer in each company the customer owns.

A typical report is shown in Example 13-3.

Example 13-3 Batch Trader application List Shares Report

CUSTOMER : RB_DEMO 09/30/2002

-----------------------------------------------------------------

COMPANY SHARES SHARE TOTAL

HELD vaLUE COST

-----------------------------------------------------------------

Glass_and_Luget_plc 120 19.00 2,280.00

IBM 1890 163.00 308,070.00

Veck_Transport 925 36.00 33,300.00

13.2.4 Buying shares

If the field, TR-REQUEST-TYPE, contains the value, BUY_SELL, and the field,

TR-SUB-TYPE, contains a value of 1, the program processes a request to buy the

number of shares in TR-NO-OF-SHARES.

After the process completes successfully, the program updates the Customer

file, DEMOS.PDPAK.CUSTFILE.

The program also produces a transaction report, as shown in Example 13-4. This

report lists the transaction file input request and the status of the processing. The

STATUS column in the report lists how the request was processed. If the

processing is successful, the message PROCESSED is printed, otherwise the

message *ERROR* is printed.

Example 13-4 Batch Trader application Transaction report listing BUY shares

----------------------------------------------------------------------------

CUSTOMER COMPANY QTY REQ-TYP STATUS

----------------------------------------------------------------------------

RB_DEMO IBM 30 BUY PROCESSED

RB_DEMO Veck_Transport 25 BUY PROCESSED

13.2.5 Selling shares

If the field, TR-REQUEST-TYPE, contains the value, BUY_SELL, and the field,

TR-SUB-TYPE, contains a value of 2, the program processes a request to sell the

number of shares in TR-NO-OF-SHARES.