com.ibm.ctg.epi
Class ScreenHandler

java.lang.Object
  com.ibm.ctg.epi.ScreenHandler

All Implemented Interfaces:

TerminalEventListener, java.awt.event.ActionListener, java.io.Serializable, java.util.EventListener

public abstract class ScreenHandler
extends java.lang.Object
implements TerminalEventListener, java.io.Serializable, java.awt.event.ActionListener

This class can be used as a base class for screen handlers. It implements some useful screen handler behaviour:

• maintains a list of ScreenEventListeners and sends ScreenEvents to them
• sets the screen AID
• sets the screen cursor position
• sends screens to CICS
• handles ActionEvents by setting the screen AID to the action command
• implements an exitScreen method, which attempts to exit the current CICS screen by setting the AID to PF3 and sending the screen to CICS

Constructor Summary

ScreenHandler()

Method Summary

void	actionPerformed(java.awt.event.ActionEvent evt) Handles an action event by converting the action command to an AID value and sending the screen to CICS.
void	addScreenEventListener(ScreenEventListener l) The specified ScreenEventListener will be called when this ScreenHandler gains control of the screen and again when it loses control.
void	exceptionOccurred(TerminalEvent evt) Handles a terminal exception.
void	exitScreen() Exit the screen.
void	fireEvent() Send appropriate event to all listeners.
AID	getAID() Get the current AID value.
int	getCursorColumn() Get the cursor column position.
int	getCursorRow() Get the cursor row position.
boolean	isHandling() Returns true if the ScreenHandler is handling the current screen.
void	removeScreenEventListener(ScreenEventListener l) Remove this ScreenEventListener from the internal list.
void	send() Send the screen to CICS.
void	setAID(AID aid) Set the AID.
void	setCursor(int row, int col) Set the cursor position.
void	terminalConnected(TerminalEvent evt) Handles a terminal connect event.
void	terminalDisconnected(TerminalEvent evt) Handles a terminal disconnect event.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.ibm.ctg.epi.TerminalEventListener

handleScreen

Constructor Detail

ScreenHandler

public ScreenHandler()

Method Detail

addScreenEventListener

public void addScreenEventListener(ScreenEventListener l)

The specified ScreenEventListener will be called when this ScreenHandler gains control of the screen and again when it loses control. The ScreenEventListener object is added to a list of ScreenEventListeners managed by this ScreenHandler, it can be removed with removeScreenEventListener. Note: the JavaBeans specification does not require listeners to run in any particular order.

Parameters:

l - the ScreenEventListener

See Also:

removeScreenEventListener(com.ibm.ctg.epi.ScreenEventListener)

removeScreenEventListener

public void removeScreenEventListener(ScreenEventListener l)

Remove this ScreenEventListener from the internal list. If the ScreenEventListener isn't on the list, silently do nothing.

Parameters:

l - the ScreenEventListener

See Also:

addScreenEventListener(com.ibm.ctg.epi.ScreenEventListener)

fireEvent

public void fireEvent()

Send appropriate event to all listeners.

See Also:

addScreenEventListener(com.ibm.ctg.epi.ScreenEventListener)

terminalConnected

public void terminalConnected(TerminalEvent evt)

Handles a terminal connect event. This method does not do anything.

Specified by:

terminalConnected in interface TerminalEventListener

Parameters:

evt - the EPI event sent

terminalDisconnected

public void terminalDisconnected(TerminalEvent evt)

Handles a terminal disconnect event. Sets the terminal variable to null, and sends the screenUnhandled event to any listeners.

Specified by:

terminalDisconnected in interface TerminalEventListener

Parameters:

evt - the EPI event sent

exceptionOccurred

public void exceptionOccurred(TerminalEvent evt)

Handles a terminal exception. This method does not do anything.

Specified by:

exceptionOccurred in interface TerminalEventListener

Parameters:

evt - the EPI event sent

isHandling

public boolean isHandling()

Returns true if the ScreenHandler is handling the current screen.

Returns:

true if handling, false otherwise

setAID

public void setAID(AID aid)

Set the AID.

Parameters:

aid - the AID

send

public void send()

Send the screen to CICS.

setCursor

public void setCursor(int row,
                      int col)

Set the cursor position.

Parameters:

row - the cursor row

col - the cursor column

getAID

public AID getAID()

Get the current AID value.

Returns:

the aid

getCursorRow

public int getCursorRow()

Get the cursor row position.

Returns:

the cursor row

getCursorColumn

public int getCursorColumn()

Get the cursor column position.

Returns:

the cursor column

actionPerformed

public void actionPerformed(java.awt.event.ActionEvent evt)

Handles an action event by converting the action command to an AID value and sending the screen to CICS. This method is provided as a simple way to make a button press set the AID and send the screen.

Specified by:

actionPerformed in interface java.awt.event.ActionListener

Parameters:

evt - the action event

exitScreen

public void exitScreen()

Exit the screen. You may need to override this method, which by default sets the aid to PF3 and sends the screen back to CICS.