Implementing Object Type Mapping

In TopLink, you can match a fixed number of database values to Java objects through object type mappings. In the advanced tutorial, each employee's gender is stored as a single letter in the database field (M or F), but the value is the full name (Male or Female).

To map the gender attribute:

1. Expand on the Employee descriptor in the Navigator pane.

2. 
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   Select the gender attribute and click the Object-Type Mapping button in the mapping toolbar.

   Figure B-37 Object-Type Mapping Tab

   
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3. In the Database Field, select the GENDER field from the EMPLOYEE table.

4. Select String as the Database Type, and String as the Object Type.

5. Click Add and create the following database mappings:

   Database Value	Object Value
   F	Female
   M	Male

   
   

6. 
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   Click Save on the toolbar or choose File >  Save Project to save the project.