OFBiz workflow source code learning (1)-wfrequester Interface

The wfrequester interface is an interface that has a direct relationship with the execution and results of workflow flows. It represents a request for the work to be done.

Knowledge point: the worker mer of the wfrequester interface is wfprocess. A wfrequester interface can correspond to several wfprocesses.

Sample Code:

Protected map export MERs = NULL;

This. Merge MERs = new hashmap (); // constructs the map of proces and requester.

Schedulmers. Put (process, requester); // registerprocess () registers process for requester

The following method is related to the Timer:

/**

* @ See org. OFBiz. Core. workflow. wfrequester # howmanyperformer ()

* Obtain the size of the timer.

*/

Public int howmanypolicmer () throws wfexception {

Return radimers. Size ();

}

/**

* @ See org. OFBiz. Core. workflow. wfrequester # getiteratorperformer ()

* Get the timer iterator

*/

Public iterator getiteratorperformer () throws wfexception {

Return radimers. keyset (). iterator ();

}

/**

* @ See org. OFBiz. Core. workflow. wfrequester # getsequenceperformer (INT)

* Get the sort Mer In the list form

*/

Public list getsequenceperformer (INT maxnumber) throws wfexception {

If (maxnumber> 0)

Return new arraylist (sort MERs. keyset (). sublist (0, (maxnumber-1 ));

Return new arraylist (sort MERs. keyset ());

}

Knowledge Point: The wfrequester interface is often used as an interface to start the process object.

As a process starter, it usually does three things:

1) Setting up the context

2) start the process

3) Get the status and results

Knowledge Point: association between the wfrequester interface and wfprocess. Generally, there are two application scenarios:

1) workflow process evolution: in this case, wfactiworkflow is refined into wfrequester, so that it has a executor wfprocess. When wfprocess executes a request, it executes an activity.

2) wfrequester connects wfprocess to other applications.

Knowledge Point: wfprocess generally uses the void receiveevent (wfeventaudit event) method to notify the workflow event to the request.

When an activity is completed, interrupted, or aborted, the requester must be notified.

Sample Code:

/**

* @ See org. OFBiz. Core. workflow. wfrequester # receiveevent ()

*/

Public synchronized void receiveevent (wfeventaudit event) throws wfexception, invalidperformer {

// Shocould the source of the audit come from the process? If so use this.

Wfprocess process = NULL;

Try {

Process = (wfprocess) event. Source (); // The event is from process

} Catch (sourcenotavailable SNA ){

Throw new invalidpolicmer ("cocould not get the specified mer", SNA );

} Catch (classcastexception CCE ){

Throw new invalidperformer ("not a valid process object", CCE );

}

// If the event source is not the process associated with the requester, an exception is thrown.

If (process = NULL)

Throw new invalidperformer ("No timer mer specified ");

If (! Extends MERs. containskey (process ))

Throw new invalidperformer ("timer mer not assigned to this requester ");

Genericrequester Req = NULL;

// If the event source is a process associated with requester, the status and result are obtained.

If (sort MERs. containskey (process ))

Req = (genericrequester) reducers. Get (process );

If (req! = NULL)

Req. receiveresult (process. Result ());

}