# Substituting Extended Entity Objects

Substituting an extended Entity Object allows any changes made to the original Entity to be made available to all of its instances in the rest of the application. For example, if you have added any new attributes or business logic to the extended Entity Object, substitution will allow code in other parts of the application to use it.

## Using JDeveloper to Substitute Extended Entity Objects

Use the Substitutions panel of the Business Components Project wizard to substitute an extended Entity Object throughout your application. For the procedure to substitute an Entity Object, see To Substitute Business Components. The framework makes an addition to the to the Substitutes section of the project's `.jpx` file which identifies the name of the original Entity Object and the name of the extended Entity that should be used instead.

For example, if you use the Substitutions panel of the Business Components Project wizard to substitute the extended Entity Object `NewEmpEx` for the original Entity Object `Emp` throughout your application, the framework adds a line to the `Substitutes` section of the project's XML file. A portion of the project's XML file is included below:

       ...
    <Substitutes>
          <Substitute OldName ="package27.Emp" NewName ="Extender.NewEmpEx" />
    </Substitutes>
       ...