Chapter 5. Using WebSphere Studio 121
The BPEL editor can roughly be split up into eight separate areas, labeled 1 to 8
in Figure 5-24 on page 120.
1. Palette - Icons of the activities that can be dragged to the process area. Note
that some of the icons on the palette actually open drop-downs when clicked.
An example of this can be seen in Figure 5-26 on page 122.
2. Variables - Defined variables for the process.
3. Process area - Section on the canvas to visually arrange the activities.
4. Action bar - Series of actions related to the currently selected activity.
5. Partner links - Partner links that are the external users or services that
interact with this process.
6. Canvas - Area that contains all visual elements of the editor.
7. Details - Situated below the canvas, allows the currently select activity to be
configured. Reflects the parameters available for the selected activity.
8. Correlation sets - Shows the defined correlation sets for the process.
Figure 5-25 Drop-down list from the palette
5.6.3 Activities and their icons
An overview of the available BPEL4WS process activities is given in Table 5-4 on
page 122.
clicking the Pick icon
opens the dropdown menu
shown on the right
122 Using BPEL Processes in WebSphere Business Integration Server Foundation - Business Process Integration and Supply Chain Solutions
The icons given in the table are what appear in the process area of the canvas.
The icon you would choose in the activities palette looks like the small icon in the
top center of these icons.
Figure 5-26 shows the invoke activity to demonstrate this. You can see that the
small icon on the right, which you choose in the activity palette, is the same as
the small upper center of the icon that appears on the process area
Figure 5-26 Palette icons
Table 5-4 WebSphere Process Choreographer activities
Activity Description
The invoke activity performs an operation. The operation is defined by
a partner link and may be synchronous or asynchronous.
The receive activity waits for an external input to the process before
continuing. The operation supported by the receive activity is defined
by a partner link.
The reply activity sends a message to the partner defined by a partner
link. This is typically used in processes that need to return a message
to the partner that instigated the process.
The pick activity waits for an incoming message and selects a path
appropriate to the first message received. A time-based path can be
configured to manage situations where no message is received. A
partner link is associated with each message path.
The staff activity delegates a task within the process to a human. The
user interface in this case is either a custom application based on the
process choreographer API or the Web client provided that comes with
WebSphere Business Integration Server Foundation.
The transformer activity maps the contents of one or more message
types to the contents of another.
Activity icon as seen in
the process area
Icon chosen from
palette to produce
this activity
Chapter 5. Using WebSphere Studio 123
The assign activity copies information from one part of the process to
another.
The switch activity evaluates the conditions on a series of control paths
and follows the first one that matches.
The while activity repeats the activities that it contains as long as a
condition is met.
The wait activity stops the process until a point in time has occurred or
a time interval has elapsed.
The sequence activity defines a serial control path within a process.
The flow activity defines a potentially parallel control path within a
process.
The terminate activity stops the process immediately without
performing any compensation or fault handling. The behavior of this
activity depends on the location within the process.
The throw activity signals that an error has occurred. This is typically
handled by a fault handler element associated with a higher level of
process structure.
The empty element does nothing. It can be used as a placeholder
during process design, and then changed to the appropriate activity
when the process is implemented.
Java code can be embedded into the process using the JavaSnippet
activity. While it is possible to embed business logic into this type of
activity it is not advisable, as it removes the clarity of the process
modelling. Snippets are designed to perform lightweight utility activities
such as data mapping.
Activity Description

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