Working with Transparent Indirection

Transparent indirection allows you to declare any relationship attribute of a persistent class that holds a collection of related objects as a java.util.Collection, java.util.Map, java.util.Vector, or java.util.Hastable. OracleAS TopLink will use an indirection object that implements the appropriate interface and also performs Òjust in timeÓ reading of the related objects. When using transparent indirection, you do not have to declare the attributes as ValueHolderInterface.

You can specify transparent indirection from the OracleAS TopLink Mapping Workbench. Newly created collection mappings use transparent indirection by default if their attribute is not a ValueHolderInterface.

Specifying Transparent Indirection

Use this procedure to use transparent indirection.

Using Transparent Indirection:

1. In the Navigator pane, select the attribute. The mapping tab appears in the Editor pane.

Figure 6-6 Sample Mapping Properties

Description of the illustration tranindr.gif

1. On the General tab, click the Use Indirection option for attributes that use indirection.

2. Select the Transparent indirection option.