The following information aims to highlight the different steps involved in creating a simple Java applet which integrates information from multiple CICS 3270 based applications.

The tutorial will show:

	How to generate JavaBeans which navigate through legacy 3270 applications
	How to identify variable data fields for passing between applications
	How to integrate the 3270 emulator beans and navigation beans with your Java development environment

The products used for this tutorial include UniKix 3270 Pathway software from Clerity, as well as the Sun Java Studio (a Java Integrated Development Environment), and Java Development Kit (JDK) v1.4. A screen capture of the finished Java applet can be viewed at the end of this document.

The first step in the creation of an applet or application that integrates multiple 3270 based backend applications, involves working out exactly what data you want to extract from each application. To do this you must first determine the path through each application, noting each keystroke and menu selection. Once this has been established you can then identify variable data fields for input and output.

For our demo we have two different CICS applications that we wish to extract data from. The first is an accounting application that contains user details such as name, address, and credit limit. The second is a stockbroking application that allows a user to buy and sell stock, and/or view their portfolio. Figures 1 and 2 below present a digramatic view of each application:

Path:	Log on, enter surname, extract returned data from display screen
Input:	Surname
Output:	Account number, name, address

Table 1: Proposed path including input/output for application 1

Path:	Log on using account number from first application, main menu, select valuation, extract total portfolio value data
Input:	Account No.
Output:	Total portfolio value

Table 2: Proposed path including input/output for application 2

UniKix 3270 Pathway software includes an automatic navigation recording function that allows you to navigate through an application. Whilst navigating, 3270 Pathway automatically records the pathway, generates the appropriate Java code and delivers it as a JavaBean. At any time during the recording UniKix 3270 Pathway technology allows you to define variables to be used as input to the application, or for storing captured 3270 data.

Figure 3 below shows the UniKix 3270 Pathway software development environment.

The next three graphics provide a more detailed description of the UniKix 3270 Pathway software recording process.

Once you have finished recording, you select File, Save from the main menu (not shown in Figure 3) to compile the generated Java source, and create the Java Bean. Each bean is then ready to be integrated into the Java development environment of your choice.

We decided to use an Integrated Development Environment (IDE) to create our applet. Creating an applet using an IDE is relatively simple, requiring the developer to write a minimal amount of code. You must first create a new project, then add to it a new applet or application. You then define and add the new beans created using 3270 Pathway. Once defined, you can then create the interface by dragging and dropping GUI components from the IDE menu bar.

The mouse-clicked event method of the "Run Demo" button performs the following:

• Assigns a 3270 Pathway Emulator to each bean
• Calls the bean's performWork() method
• Returns the results and displays them in defined output fields

A full listing of the Java source code for the "Run Demo" button mouse-clicked event method, can be seen below:

void runDemo_mouseClicked(MouseEvent e) {

// Change status of rundemo button
runDemo.setEnabled(false);

// assign 3270 Pathway Emulator to each Bean -
// acctClass1 (accounting application bean)
// dmoiClass1 (stockbroking application bean)
acctClass1.setKixEmulator(ke1);
dmoiClass1.setKixEmulator(ke2);

// get surname from list
String surn = choiceName.getSelectedItem();

// surname is used as input to accounting app.
acctClass1.setSurname(surn);

// call performWork() method of the accounting app.
acctClass1.performWork();

// output details from accounting application
String acctNo = acctClass1.getDetails_acctNo();
acctNoField.setText(acctNo);

String first = acctClass1.getDetails_first();
firstNameField.setText(first);

String middle = acctClass1.getDetails_initial();
middleInitialField.setText(middle);

String surname = acctClass1.getDetails_surname();
surnameField.setText(surname);

String address = acctClass1.getDetails_address();
addressField.setText(address);

// Use acctNo from accounting app. to login to the stockbroking app.
dmoiClass1.setUserID(acctNo);

// call performWork() method of stockbroking app.
dmoiClass1.performWork();

// Output total portfolio value
String total = dmoiClass1.getTotalValue();
valueField.setText(total);

// Disconnect both terminals
ke1.disconnect();
ke2.disconnect();

// change status of rundemo button
runDemo.setEnabled(true);

}

A screen capture of the finished applet can be seen below. The actual finished applet uses the created JavaBeans to access a UniKix TPE software region (Clerity's native implementation of CICS for Open Systems platforms) via a Telnet 3270 connection. The results are then displayed in the newly created Java interface.

	Download the UniKix 3270 Pathway software datasheet
	View a UniKix 3270 Pathway case study
	Contact a Clerity Mainframe Rehosting specialist today to discuss UniKix 3270 Pathway software in more detail