Evaluation and Maintenance of Type Linkage Table (SAP Library

Evaluation and Maintenance of Type Linkage Table

Use

The type linkage describes the assignment of a receiver function module and a receiver type to a particular combination of object type and event. This linkage is entered into the type linkage table.

The table must be completed if a response is always to be made to an event of a particular object type, even if the linkage is to be instance-based. The type linkage table is evaluated at runtime by the event manager.

The event receiver should make the entry in the type linkage table using a function module provided.

If events are used in SAP Business Workflow (as triggering and terminating events, for wait steps), the entries required in the linkage tables are made by the workflow system.

If you enter an event as a triggering event of a task, for example, the following entries are made automatically:

Object type and event ID

Task to be started as receiver type

Function module SWW_WI_CREATE_VIA_EVENT as receiver function module

Indicator global set in background

When the linkage is activated within task definition, the indicator enabled is also set in the type linkage table.

Integration

Transport and client copy

Entries in the client-specific type linkage tables are written automatically into a Customizing transport request if the client is configured (in table T000 ) for changes to be recorded automatically. All entries are then transported including activation indicators.

In the case of client copy, you should note that the event receiver linkages are copied into the target client, but are always deactivated in the target client.

The activation indicator of each individual event receiver linkage is only copied with client copy if explicitly requested (parameter option for copying tables of class A).

Process Flow

The event manager begins the evaluation of the type linkage table when it is notified of the ID of a created event. For event handling to take place, either the event created and its triggering object type or the created event and a supertype of the triggering object type must be entered in the type linkage table.

Only those entries in the type linkage table for which the indicator Event linkage activated is set are included by the event manager in the evaluation.

If the event manager finds an entry in the type linkage table for the event created, the following processing steps take place:

The receiver type function module for determining the receiver type is called if specified in the type linkage table.

If the event linkage is designated a global event linkage, the following occurs:

The check function module is called if specified in the type linkage table.

If this function module terminates without an exception (or if no check function module is specified), the receiver function module is called with the transfer parameters event, receiver type and event container.

The instance linkage table is not evaluated.

If the event linkage is not designated a global event linkage, the instance linkage table is evaluated.

If an error occurs within the function module SWW_WI_CREATE_VIA_EVENT (task missing or has errors, problems with tRFC), a mail is sent to the workflow system administrator.

Features

Structure of the type linkage table

The following fields are available in the type linkage table:

Object type

Type of object for which the event is created.

Event

Event created.

Object type and event must be defined in the Business Object Repository.

Receiver type

Receiver function module

Check function module

Receiver type function module

Destination

Standard name of a logical RFC destination in which the receiver function module is called. If no destination is specified, the receiver function module is called locally in the destination WORKFLOW_LOCAL_<Client> .

The workflow runtime system only uses events locally and does not complete this field. Do not enter a destination.

For further information, refer to Destination Types.

Indicator: Global

If the event linkage is shown as global, the receiver function module specified is called each time the object type/event pair occurs, irrespective of the triggering object instance.

The instance linkage table is not evaluated for this event.

The indicator is set automatically by the workflow system:

The indicator is set for triggering events.
The indicator is not set for terminating events and wait steps.

This indicator can only be set manually with the following function modules:

SWE_EVENT_REC_TYPE_GLOBAL

SWE_EVENT_REC_TYPE_NOT_GLOBAL

Indicator: Type linkage activated

If you set this indicator, the type linkage between the event creator and the event receiver is activated.

Indicator: Enable event queue

This indicator is only evaluated if the event queue is active.

If the indicator is set, the event receiver is started via the event queue. If the indicator is not set or the event queue is not active, the receiver is started immediately.

Behavior if error feedback

The system presetting maintained on the tab page Basic data in event queue administration can be adopted or revised.

Receiver status

The status of the event receiver affects the starting of the receiver. In general, the receiver linkage must be active to start the receiver. The status of the receiver linkage has the following effects:

No errors

If the receiver linkage has the status no errors, the receivers are started by the system. They can be started directly or via the event queue.

Errors

If the receiver linkage has the status errors, the receiver is not started immediately, but is put into the event queue automatically instead. There the entry is assigned the status Waiting because of errors. So the receiver is not started, but there is an opportunity to start the receiver again after the error has been removed. Triggered events do not get lost even with linkages that have errors. The event receivers can be started again using the tab page Linkages with errors.

Maintenance of type linkage table

You have to process the type linkage table manually if:

You use event control within your own non-workflow developments.

You want to analyze the entries made by the workflow system.

You want to add a check function module at a later date.

You want to activate an event receiver linkage.

You want the events of a particular linkage to use the event queue.

Otherwise, the maintenance of the type linkage table (entering linkages for triggering or terminating events) is carried out by the workflow system.

It is possible to create a full entry in the type linkage table using the following function module:

SWE_EVENT_REC_TYPE_ENTER.

APIs are also available for processing individual fields in the type linkage table.

Name of function module	Explanation
SWE_EVENT_REC_TYPE_CHECK_FB	Changing the check function module for the event receiver
SWE_EVENT_REC_TYPE_DISABLE	Deactivating a type linkage
SWE_EVENT_REC_TYPE_ENABLE	Activating a type linkage
SWE_EVENT_REC_TYPE_FB	Changing the receiver function module
SWE_EVENT_REC_TYPE_GET_FB	Changing the function module for the type determination of the event receiver
SWE_EVENT_REC_TYPE_GLOBAL	Setting a global event linkage
SWE_EVENT_REC_TYPE_NOT_GLOBAL	Deleting a global event linkage
SWE_EVENT_REC_TYPE_READ	Reading a type linkage

Use the following function module to delete an entry from the type linkage table:

SWE_EVENT_REC_TYPE_DELETE

If you make entries in the type linkage table, make sure you delete them again when a type linkage is no longer expected. Ensure that there are no instance linkages for this type linkage.

Activities

To maintain the type linkage table, choose Tools ® Business Workflow ® Development ® Utilities ® Events ® Type linkages.

The overview displays the existing type linkages with details of object type, event and receiver type.

Choose Edit ® New entries to add new entries to the type linkage table.

Choose Goto ® Details to revise entries.