When you author a JET transformation, you start with an example of the application code that you want to produce, which is typically one or more Eclipse projects. This example application is called the exemplar. You then use the authoring editor to identify the parts in the exemplar that vary from one application to the next. This identification process produces a data model that represents the variable aspects of the exemplar. You can also associate code-generation actions with elements in the model. Finally, you use the editor to create JET templates from exemplar files, and replace text with references to the model that is developed.
After the model-to-text transformation and corresponding metamodel are created, you can use basic XML input models to validate the transformation. In addition, other Java code can use the transformation by using tools such as the model-to-model mapping transformation tools.