com.iscobol.rts

Interface CallHandler

public interface CallHandler

The aim of this interface is to provide entry points before and after each CALL and CANCEL statement.

Here is a sample class that prints log messages on the system output before and after each CALL and CANCEL statement:

 import com.iscobol.rts.CallHandler;
 import com.iscobol.rts.IscobolCall;
 import com.iscobol.rts.WithName;
 
 public class MyCallHandler implements CallHandler {
     private String getName(IscobolCall call) {
        return call instanceof WithName ? ((WithName) call).getName() : 
                                          call.getClass().getName();
     }
     public void afterCall(IscobolCall call, Object[] argv) {
         System.out.println("AfterCall: " + getName(call) );
     }
     public void afterCancel(IscobolCall call) { 
         System.out.println("AfterCancel: " + getName(call) );
     }
     public void afterCancelAll() {  
     }
     public void beforeCall(IscobolCall call, Object[] argv) {
         System.out.println("BeforeCall: " + getName(call) );
     }
     public boolean beforeCancel(IscobolCall call) {
         System.out.println("BeforeCancel: " + getName(call) );
         return true;
     }
     public boolean beforeCancelAll() {        
         return true;
     }
 }

To install this class in your runtime session, you will set:

    iscobol.call_cancel.hook=MyCallHandler

Note that the instance of this class is shared among all the programs in the same run unit. A separate instance is generated for every new Client in thin client environment and for every program called via CALL RUN, but within a standard programs chain (e.g. PROGA calls PROGB, then PROGB calls PROGC) the same instance of the hook class is used.

Method Summary

Modifier and Type	Method and Description
void	afterCall(IscobolCall call, Object[] argv) Defines the actions to be performed after returning from a called program.
void	afterCancel(IscobolCall call) Defines the actions to be performed after canceling a program.
void	afterCancelAll() Defines the actions to be performed after a CANCEL ALL statement.
void	beforeCall(IscobolCall call, Object[] argv) Defines the actions to be performed before entering in a called program.
boolean	beforeCancel(IscobolCall call) Defines the actions to be performed before canceling a program.
boolean	beforeCancelAll() Defines the actions to be performed before a CANCEL ALL statement.

Method Detail

afterCall

void afterCall(IscobolCall call,
               Object[] argv)
        throws CallOverflowException

Defines the actions to be performed after returning from a called program. Note that this method is executed only if the called program was actually loaded.

Parameters:

call - the instance of the called program

argv - the parameters that were passed to the program

Throws:

CallOverflowException

afterCancel

void afterCancel(IscobolCall call)

Defines the actions to be performed after canceling a program. Note that this method is executed only if the cancelled program was actually in memory.

Parameters:

call - the instance of the cancelled program

afterCancelAll

void afterCancelAll()

Defines the actions to be performed after a CANCEL ALL statement.

beforeCall

void beforeCall(IscobolCall call,
                Object[] argv)
         throws CallOverflowException,
                MapCallException

Defines the actions to be performed before entering in a called program. Note that this method is executed only if the called program is actually loaded.

Parameters:

call - the instance of the called program

argv - the parameters that were passed to the program

Throws:

CallOverflowException

MapCallException

beforeCancel

boolean beforeCancel(IscobolCall call)

Defines the actions to be performed before canceling a program. Note that this method is executed only if the cancelled program is actually in memory.

Parameters:

call - the instance of the cancelled program

Returns:

the result of the operation.

beforeCancelAll

boolean beforeCancelAll()

Defines the actions to be performed before a CANCEL ALL statement.

Returns:

the result of the operation.