Implementing a Transformation Mapping

Use transformation mappings for specialized translations between how a value is represented in Java and in the database. The method takes a database row as an argument and is called whenever an object is written to the database. The method returns the value from the object that should be written to the field.

In the advanced tutorial, the transformation method corresponds to a single argument method on the Employee class and extracts the values from the fields, placing them into the NormalHours array.

To map the normalHours attribute:

1. Expand the Employee descriptor in the Navigator pane.

2. Click the normalHours attribute of the Employee descriptor.

3. 
   Description of the illustration trmapbtn.gif
   
   Click the Transformation Mapping button on the mapping toolbar.

4. Use the Database Row -> Object Method drop-down list to select the bulidNormalHours method.

5. Click the Add button to create the following Object->Field Methods:

   • Database Field: START_TIME, Method: getStartTime

   • Database Field: END_TIME, Method: getEndTime

   Figure B-43 Transformation Mapping Tab

   
   Description of the illustration trmapdbr.gif
   
   

6. 
   Description of the illustration savebtn.gif
   
   Click Save on the toolbar or choose File >  Save Project to save the project.