Specifying Data Mappings

This chapter describes how to use and manage data mappings in the IPP Eclipse modeler.

For details on the general concept of data mappings in IPP, please refer to chapter Workflow Data in our Concepts part.

Creating Data Mappings

To create a data mapping for an activity:

  1. Open the properties dialog of the activity.
  2. Select In Data Mappings or Out Data Mappings in the left side of the dialog.
  3. Choose a context type in the data mapping pane. Possible contexts are:

    Section Context Types" describes these types in detail.

  4. Select Add.

    Add an In Data Mapping
    Figure: Add an In Data Mapping

  5. Edit the data mapping details in the details pane.

Editing Data Mappings

Data mappings can be modified by selecting their connection symbol in the diagram and then editing its properties in the details pane or by opening the properties dialog of the corresponding activity.

Depending on the type of the chosen data mapping, the details pane will show editing controls for:

Data Mapping Properties Dialog
Figure: Data Mapping Properties Dialog

Setting Access Points

Access points are named parameters to set or get values associated with a model element at runtime. Refer to section Access Points of chapter Workflow Data for details on the concept of using access points in IPP.

Access Point Selection
Figure: Selecting an access point

Access Points can be used as values from events, e.g. the caught exception from an exception event:

Event Access Point Example
Figure: Event Access Point Example

Setting Access Point Paths

Depending on the type of the access point an input or output access point path can be applied to it.

Examples

The following screenshot shows an example usage for getting the label of a document version access point:

Access Point Path Example
Figure: Document Version Label Access Point Path example

The following screenshot shows an example usage for executing a Java method on an access point:

Access Point Path Example
Figure: Java Method Access Point Path example

Changing the Order of Data Mappings

All data mappings are executed in the order specified in the model. Data mappings may be reordered by selecting a data mapping in the data mapping properties pane in the properties dialog of the activity and clicking the Move Up or Move Down button.

Data Mapping Order
Figure: Changing the order of data mappings

Context Types

The provided context types for data mappings depend on the activity type. The following context types are available:

Default Context

The default context is used for manual or route activities. Please also refer to section Data Mappings of chapter Manual Activities for more details.

In case you add a default context In-data mapping, the property page additionally displays two checkboxes to select if the In-data mapping should be constant or data-bound.

In-Data Mapping Checkboxes
Figure: Checkboxes for constant or data-bound In-data mapping

Note that switching between using constant and data-bound selection always deletes all data-mapping properties entered for the former selection.

Using constant In-data mapping

To use constant In-data mapping, select the DataMapping is Constant. checkbox. In the Type drop-down list choose a data type. The following primitive data types are supported:

Constant Data Type
Figure: Select a constant data type

Optionally enter a default value.

Using data-bound In-data mapping

Select DataMapping is Data bound. to use a data-bound In-data mapping, which is the default behavior.

Data Bound Mapping
Figure: Select data-bound mapping

Engine Context

The engine context contains a Java style access point activityInstance, which provides access to the attributes of the corresponding activity instance at runtime.

Engine Context
Figure: Engine Context

Noninteractive Application Context

Noninteractive application context is provided for non-interactive application activities. It offers all access points of the associated non-interactive application.

Noninteractive Application Context
Figure: Noninteractive Application Context

Interactive Application Context

The application context provides specific contexts for interactive applications. It offers the access points defined in the application context itself.

Process Interface Context

The processInterface context is available for process interface mappings, e.g.:

Process Interface Context
Figure: Process Interface Context

Process interface data mapping is required when one model is referring to another model. Suppose the referred subprocess has IN parameters defined and it returns the result. In this case, the called process should know the IN and OUT parameters. So if the referred process has exposed the parameters then you need to provide the data mappings in the process interface context.

Note that the data type specified in the formal parameters should match with the data type specified in the consumer model. For example, you have defined structure data type in the provider model. To access the same structured data in the consumer model, you need to drag and drop the structured data and reference through the data mappings. For more information on how to drag and drop referenced elements, please refer to the section Dragging and Dropping the Referenced Elements of the External Model Resources chapter. For more information, you can also refer to the chapter Outline View .

Open the Property page of the referred subprocess activity in the consumer model and click on In Data Mappings

Subprocess In Data Mappings
Figure: In Data Mapping

Select the processInterface context and click the Add button.

In Data Mapping - Process Interface Context
Figure: In Data Mapping - Process Interface Context

Specify the parameters and click on Apply.

Process Interface Context - Parameters
Figure: Process Interface Context - Parameters

Similarly, you can provide the out data mappings.

Data Mapping Connection

After data mappings are created they render automatically in the Process Workbench as connections between the activity symbol and the data symbol. There is at most one data mapping connection between an activity and a data, summarizing all existing data mappings for them. The data mapping direction is indicated by arrows:


Figure: An In Data Mapping Connection

There is a shortcut to create a first data mapping between an activity and a data: in the diagram containing the activity and the data element you can map the data as the activity's input/output. To do this, proceed as follows:


Figure: Create a In Data Mapping

An In data mapping is created, visualized by a data mapping connection.

If you have created at least one link type with source type Data and target type Activity, you have the choice to select between these custom link types and the standard data mapping connection type. Please refer to chapter Specifying Arbitrary Link Types for information on custom link types.


Figure: Select the Link Type for Data Mapping
 

To create an Out data mapping, this works the other way around:


Figure: Create an Out Data Mapping

Deleting Data Mappings

A data mapping can be deleted by