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| <body> |
| <h1>Tutorial 2 - Creating a Composite</h1> |
| <p> |
| In this tutorial we will create a TransientComposite interface that ties all pieces together. |
| The TransientComposite interface is a regular Java interface which extends the interfaces you |
| want to expose from your domain model, and which uses various annotations to declare |
| what Fragments to include. Fragments include Mixins, Concerns, SideEffects and Constraints. |
| In this tutorial we will only use Mixins. When a TransientComposite is instantiated at runtime |
| the framework will inspect the interface to determine what the TransientComposite instance should |
| look like in terms of used Fragments. |
| </p> |
| <p> |
| In Zest™ all method parameters are considered mandatory unless marked as @Optional. Therefore you can |
| remove the null checks in the Mixin. If a null value is passed in an exception will be thrown by Zest™. |
| </p> |
| <p> |
| Steps for this tutorial: |
| </p> |
| <ol> |
| <li>Create an interface that extends the domain interface HelloWorld and |
| org.qi4j.api.composite.TransientComposite. |
| </li> |
| <li>Add a @Mixins annotation to it with the name of the Mixin as argument.</li> |
| </ol> |
| </body> |
