1. In Model project, right click on any package, select 'New Association'.
2. Now, 'Create Association' wizard appears -> In the 'Name' stop, Give Name for the Association, select/give package for the Association. The Association Name is generally follows the convention <SourceEO>To<DestinationEO>. E.g., DeptEOToEmpEO.
3. Click 'Next' -> In the 'Entity Objects' section, select the Source and Destination EOs and the attributes in Source and Destination EOs on which you want define the association.
4. Click 'Next' -> In the 'Assocation Properties' section, specify the properties if applies. For e.g., if the assocation is composite, check the box 'Composite Association'.
5. Click 'Next' -> In the 'Edit Assocation Query' section, verify if the where clause for the association generated is right. You can modify the query where clause if needed.
6. Click 'Next' -> 'Summary' displays the summary of the created association -> Click 'Finish'.
7. Now, you'll find the newly created Association in model project under the specified package.
8. Once, you create the association between EmpEO and DeptEO, Jdeveloper will add the association accessors in each of the EOs.