Creating navigation nodes

Adding a navigation node

Navigation nodes are elements which belong to the profile's reference metamodel. Examples of navigation nodes could be the “Package”, “Class” or “Operation” metaclasses. A “Package” navigation node would browse all the packages belonging to a given package, while a “Class” navigation node would browse the classes belonging to the package in question. An “Operation” navigation node would browse all the operations belonging to a given class.

To add a new navigation node to your diagram, code or documentation template, simply click on the icon on the top-left of the template design window and select the type of UML element you wish to retrieve using the scan method (Figure 110).

Figure 110. Creating a navigation node

Steps:

1. Click on the icon. The “Selection of a scan method” window then appears.

2. In this window, select the element you wish to scan for. Elements of the indicated type will be retrieved by this method. In our example, the scan method will return the classes belonging to a package.

3. Click on “OK” to confirm.

If you want to create a node without navigating to another element, select “Retrieve the current element” in the previous dialog box.

Navigation node properties

The properties of a navigation node are presented on the top-right of the template design window, when a navigation node has been selected, as shown in Figure 111.

Figure 111. The properties of a navigation node

Property	Description
Scan method	This property corresponds to the method used on the current element to obtain its sub-elements. In the example shown in Figure 146 above, the current element is a package and the “OwnedElementClas” method is called to retrieve the classes of this package.
Metaclass	This property indicates the metaclass returned by the scan method.
Filter	This property is used to filter elements according to their stereotypes, tagged values, notes or properties. By double-clicking on the button when the field is selected, the window shown in Figure 8-8 appears.
Triggered action	This property indicates code to be executed for each element scanned by the scan method. For example, traces can be displayed. This property is not available for code templates.
Memorize	This property is used to memorize the elements that are browsed by the navigation node. This field must contain a character string representing the name of the element to retain. This name can then be used to retrieve the memorized element.

Adding a navigation node

After adding a navigation node, you can modify the J code defined in the “Scan method” property, for example, to add a filter.

In the figure 111, instead of “OwnedElementClass”, you can replace by “OwnedElementClass.<select (IsAbstract)” to retrieve only the abstract classes.

For more information on entering J code, please see “Inserting J code”.