Step 3: Creating a Class Diagram
In this step, you will create a UML class diagram of the OE schema. This will allow you to see the objects and their relationships to each other. This step will also create a business components package containing default-generated business components: an entity object for each table, and an association for each relationship.
To generate the class diagram:
Right click on your project node (bc.jpr) and choose New UML Diagram from the popup menu.
In the New dialog, select Class Diagram and click OK.
In the Create New Class Diagram dialog box, enter oe_diagram and then click OK. A blank class diagram pane appears on the right.
In the System Navigator click on the CUSTOMERS table and drag and drop it onto the class diagram.
In the Create from Tables dialog, select Business Component Entity Objects and click OK .You may experience some delay while the UML class diagram is being created.
In a similar manner, drag and drop ORDER_ITEMS and ORDERS.
Your completed class diagram should contain the entity objects and associations in the figure below. (Notice that you can rearrange and resize them for better organization.)
In the System Navigator, notice that you have two new package nodes named onlineOrders. The first one contains the class diagram, the second one contains business components. You won't need to use the class diagram further in this tutorial, so you can collapse the top node. Note that in the figure above, CustAddressType is also generated by default. This object is a business component domain. Domains are custom datatypes and are beyond the scope of this tutorial.
In this step you created a class diagram, which generated business components for you. And while your business logic tier has all the necessary components to persist (store) data, you'll need compon