The process window in Oracle Workflow Builder graphically represents the activities (icons) and transitions (arrows) for a particular process. Each activity is a node, a logical step that contributes toward the completion of a process.
You can drag and drop activities from the navigator tree into the process window or create activities directly in the process window. The properties for an activity node may be viewed or edited by double clicking on the node in the process window with the select mouse button. You define transitions between activities by drawing arrows from one node to the next using the secondary mouse button.
Notification, function, event, and process activities make up the nodes of a process. If a process contains a process activity in its diagram, that process activity is known as a subprocess. There is no restriction on the depth of this hierarchy. To display the subprocess diagram in a process window, double-click on the subprocess activity node in the parent process window.
Transitions appear as arrows in your diagram and represent the completion of one activity and the activation of another. For an activity that completes with a result type of <None>, any transition that you draw from it simply appears as an arrow to the next activity, indicating that as long as the originating activity completes, the process transitions to the next activity.
For an activity that has a defined result type, you must associate the transition arrow that you create with one of the activity's possible results. The result that the activity returns when it completes then determines what the next eligible activity is, as defined by the results-based transitions that originate from the completed activity. For example, "Notify Approver" with a result of 'REJECTED' transitions to "Reject Requisition." See: Requisition Process Activities.
You can also create a <Default>, <Any>, or <Timeout> transition for an activity that has a defined result type. The Workflow Engine follows a <Default> transition if no other transition matching the completion result exists. The Workflow Engine follows an <Any> transition regardless of what completion result the activity returns. This allows you to include a generic activity in the process that the Workflow Engine executes in parallel with the result-specific activity. The Workflow Engine follows a <Timeout> transition if the notification activity times out before completion. See: Setting Up Background Engines.
Activities can have multiple transitions for a single result to create parallel branches.
Draw a <Timeout> transition from a notification activity to some other activity to force the process to perform the other activity if the notification activity does not complete by a specified period of time. See: To Define Nodes in a Process.
When an activity times out, Oracle Workflow marks the activity as timed out and then cancels any notification associated with the timed out activity. The Notification System sends a cancellation message to the performer only if the canceled notification was expecting a response and the performer's notification preference is to receive e-mail.
Note: You can optionally use the Send E-mails for Canceled Notifications mailer parameter to prevent notification mailers from sending any notification cancellation messages. See: Notification Mailer Configuration Wizard.
Processing then continues along the <Timeout> transition as indicated by your process definition. If a timed out activity does not have a <Timeout> transition originating from it, Oracle Workflow executes the error process associated with the timed out activity or its parent process(es). See: To Define Optional Activity Details.
Note: You must have a background engine set up to process timed out activities. See: Setting Up Background Engines.
You can create multiple transitions to a single activity in a process diagram. Sometimes these multiple transitions indicate that there are multiple ways that the process can transition to this one node and you may want the node to execute just once.
In other cases, the multiple transitions may indicate that the activity may be transitioned to multiple times because it is the starting point of a loop. In these cases, you want the activity to be reexecuted each time it is revisited.
The On Revisit flag for an activity determines whether the activity reexecutes when it is revisited more than once. It is an important flag to set for the pivot activity of a loop. On Revisit is set initially in an activity's Details property page. However, for each usage of an activity in a process, you may change On Revisit for that node in the activity's Node property page. You can also use the standard Loop Counter activity as the initial activity in a loop to control how many times a process can transition through a loop. See: Looping and Loop Counter Activity.
Tip: If you have multiple incoming transitions from parallel branches, you should always use an And, Or, or custom join activity to merge those branches. This is especially true if after merging the parallel branches, you want to create a loop in your process. By using a joining activity to merge parallel branches and designating the following activity as the start of the loop, you create a less complicated process for the engine to execute. See: Standard Activities.
Each process has to have a Start activity that identifies the beginning point of the process. You may designate any node from which it is logical to begin the process as a Start activity. When initiating a process, the Workflow engine begins at the Start activity with no IN transitions (no arrows pointing to the activity). If more than one Start activity qualifies, the engine runs each possible Start activity and transitions through the process until an End result is reached. The engine may execute acceptable Start activities in any order. Processes may contain multiple branches that each have an End activity. When the Workflow Engine reaches an End activity, the entire process ends even if there are parallel branches still in progress.
An End activity should return a result that represents the completion result of the process. The result is one of the possible values from that process activity's result type.
Start activities are marked with a small green arrow, and End activities by a red arrow, that appear in the lower right corner of the activity node's icon in the process window.