de.danet.an.workflow.tools.util
Class SimpleApplicationAgent

java.lang.Object
  de.danet.an.workflow.tools.util.SimpleApplicationAgent

All Implemented Interfaces:

ToolAgent

public abstract class SimpleApplicationAgent

extends java.lang.Object

implements ToolAgent

This is a base class for writing agents for applications that have a life cycle exceeding a single tool agent invocation, and have only state information that can efficiently be persisted as a binary large object in an RDBMs.

An example for such an application is the wait tool (see User Manual). A wait tool (or "wait application") is created by one tool agent invocation. Then another tool agent invocation waits for the completion of the wait, while yet another tool agent invocation may cause the wait tool to complete prematurely. The wait tool has state that is controlled by the tool agents and a timer provided by the enviroment. Its state is therefore completely serializable (no open sockets, tool controlled threads etc.).

This base class mainly provides access to the application directory that does all the important work.

Version:

$Revision: 1.2 $

Author:

Michael Lipp

Constructor Summary

SimpleApplicationAgent()
Creates an instance of SimpleApplicationAgent with all attributes initialized to default values.

Method Summary

protected SimpleApplicationDirectoryLocal	applicationDirectory() Return the application directory.
void	terminate(Activity activity) Terminates execution of the given activity.

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.danet.an.workflow.spis.aii.ToolAgent

invoke

Constructor Detail

SimpleApplicationAgent

public SimpleApplicationAgent()

Creates an instance of SimpleApplicationAgent with all attributes initialized to default values.

Method Detail

applicationDirectory

protected SimpleApplicationDirectoryLocal applicationDirectory()
                                                        throws de.danet.an.util.ResourceNotAvailableException

Return the application directory.

Returns:

the application directory

Throws:

de.danet.an.util.ResourceNotAvailableException - if an application directory EJB cannot be instantiated

terminate

public void terminate(Activity activity)
               throws ApplicationNotStoppedException,
                      java.rmi.RemoteException

Terminates execution of the given activity. This base implementation simply removes the application instance fom the application directory.

Specified by:

terminate in interface ToolAgent

Parameters:

activity - the activity to be canceled

Throws:

ApplicationNotStoppedException - if execution cannot be terminated (see ApplicationNotStoppedException). workflow engine should retry the tool invocation

java.rmi.RemoteException - if a temporary problem occurs and the workflow engine should retry the tool invocation