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10.1 Scenarios overview
We have one application which has been written to demonstrate the features of
the Application Development Tools. It is the Trader stock trading application. The
users of this application might be investors checking their holdings, or buying and
selling shares of stock. The application takes two forms:
Each form can access data on VSAM, DB2 or IMS/DB, also known as DL/I.
In the chapters that follow, we create scenarios based on the Trader application.
In each scenario, we deliberately introduce errors into the application to allow us
to demonstrate the functionality of the tools. We then describe, in detail, the
steps that you take to isolate the error and to correct the problem.
10.1.1 Overview of the programs
The Trader application is used to maintain a stock portfolio held by an individual.
This application enables you to:
Obtain quotes (in batch mode, you list portfolios and their values)
Buy more shares of a company’s stock
Sell currently held shares of a company’s stock
The Trader application uses two data sources:
The company source contains the stock name and the past week’s quotes. The
customer source contains a record for each customer and company that he or
she owns, including the number of shares held.
It can be two VSAM files, two DB2 tables in the MYTRADD DB2 plan, or two IMS
In the CICS application, the transaction input is taken directly from an online
user’s interactions. In the batch application, the user’s input is replaced with a
sequential file that contains several records that represent the day’s transactions.
Note: his application does not reflect real-world securities processing.It is
merely designed to demonstrate the features of the Application Development
Too l s.
Chapter 10. Introduction to the scenarios 349
Overview of the CICS program
Figure 10-1 shows the processing that occurs in the CICS application.
Figure 10-1 Trader application: single user transaction with CICS
Overview of the batch program
Figure 10-2 shows the processing that occurs in the batch application.
Note: When you invoke this application, you can use any user name and
password. But, if you want to see the status from previous trading, use the
same user name each time.
VSAM file VSAM file
CICS application with VSAM files
350 IBM Application Development Tools for z/OS and OS/390
Figure 10-2 Trader application: multiple remote site transactions with batch
10.1.2 S/390 software prerequisites
The application programs listed in Table 10-1 were created for this redbook and
are installed on our system. These application programs were designed to
demonstrate the functionality of the Application Development Tools.
Table 10-1 Application programs used in Trader application
Note: You should always list the holdings of a user name to determine the
number of shares in a portfolio before you begin to trade with it.
VSAM file VSAM file
Batch application with VSAM files
Application program Subsystem Purpose
CICS To retrieve customer information from
TRADERB Batch To process customer transactions from
sequential and VSAM files
CICS and DB2 To retrieve customer information from
TRADERD Batch and DB2 To process customer transactions from
sequential file and DB2 tables