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| <body> |
| <h1>Step 1 - Creating a ServiceComposite</h1> |
| |
| <p> |
| In this tutorial we start with basic Java classes, to simulate a very simple Library where you can borrow |
| and return books. |
| </p> |
| <p> |
| Apache Zestâ„¢ relies heavily on the use of interfaces. This makes it possible for an object |
| to externally implement a number of interfaces which internally is backed by a number |
| of Mixins, some of which you may have written yourself, and some of which may have been |
| reused. This is also true for services, which we are to cover in this tutorial. |
| </p> |
| <p> |
| The first task is therefore to refactor the code so that the methods are implemented from an |
| interface instead, and to essentially make the identical "application" into a Zestâ„¢ application. |
| We also want the Book to be a ValueComposite. |
| </p> |
| |
| <p>Steps for this tutorial:</p> |
| <ol> |
| <li>Make the Book into a ValueComposite.</li> |
| <li>Make the Library an interface with the same methods. We call this a <i>Mixin Type</i></li> |
| <li>Create a LibraryMixin class, which implements the Library interface.</li> |
| <li>Create a LibraryService that binds the LibraryMixin.</li> |
| <li>The LibraryMixin will need to be injected with the <code>ValueBuilderFactory</code> in the |
| <code>@Structure</code> scope. |
| </li> |
| </ol> |
| |
| </body> |