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    <p>First of all, in Java (5 and higher), "things" starting with a <code>@</code> (e.g. <code>@Deprecated</code>) are called <a href="http://download.oracle.com/javase/tutorial/java/javaOO/annotations.html" rel="nofollow">annotations</a>.</p> <blockquote> <p><em>Annotations</em> provide data about a program that is not part of the program itself. They have <strong>no direct effect</strong> on the operation of the code they annotate.</p> </blockquote> <p>Your JavaBeans needs to be configured to a scope if you want to use it in JSF (Definitions can be found <a href="http://www.java-samples.com/showtutorial.php?tutorialid=472" rel="nofollow">here</a>).</p> <ul> <li><code>@RequestScoped</code>: Objects with this scope are visible from the start of the request until the end of the request. Request scope starts at the beginning of a request and ends when the response has been sent to the client. If the request is forwarded, the objects are visible in the forwarded page, because that page is still part of the same request/response cycle. Objects with request scope can use other objects with none, request, session, or application scope. If you have to think it in terms of servlet, the managed bean is stored in the <code>HttpServletRequest</code> until the end of the request (when the response is sent to the client). After that, the bean no longer exists in the request.</li> <li><code>@SessionScoped</code>: An object with session scope is visible for any request/response cycle that belongs to a session. Objects with this scope have their state persisted between requests and last until the object or the session is invalidated. Objects with session scope can use other objects with none, session, or application scope. Basically, these objects are stored in a <code>HttpSession</code> (refer to Servlets again). Each session has a session ID (known as <code>JSESSIONID</code>) that the bean is associated with.</li> <li><code>ApplicationScoped</code>: An object with application scope is visible in all request/response cycles for all clients using the application, for as long as the application is active. In terms of Servlet, this could be, managed bean stored in a <code>ServletConfig</code>.</li> <li><code>@NoneScoped</code>: Objects with this scope are not visible in any JSF page. When used in the configuration file, they indicate managed beans that are used by other managed beans in the application. Objects with none scope can use other objects with none scope.</li> </ul> <hr> <p>For <a href="http://download.oracle.com/javaee/6/api/javax/persistence/EntityManager.html" rel="nofollow"><code>EntityManager</code></a>, this is associated with persistence context. It is used to create and remove persistent entity instances, to find entities by their primary key identity, and to query over all entities. For more, refer to the JPA (Java Persistence API) Specification, or <a href="http://docs.jboss.org/hibernate/entitymanager/3.5/reference/en/html_single/" rel="nofollow">Hibernate</a>.</p> <p><a href="http://download.oracle.com/javaee/6/api/javax/inject/Inject.html" rel="nofollow"><code>@Inject</code></a>, means that the instance is injectable. They follow the infamous crase word of <em>Depency Injection</em> or <em>Inversion of Control (IOC)</em>. What this basically mean, is that when the resource (in your case <code>EntityManager entityManager</code> is needed, the JEE container instantiates the resource for you (without you needed to instantiate it directly through e.g. a constructor, etc.).</p> <p>I have no clue what <code>@DataRepository</code> means. Never seen it before.</p> <p>I hope this helps you.</p>
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    1. COthanks that helped a lot. Im a bit confuesed about the "create and remove persistent entity instances" what are entities and entity instances?
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    2. COpersistent data are data which can be stored in a persistent storage device (e.g. memory, RAM, etc.). A persistent object, in Java, is an object that is `Serializable` and that contains attributes (that is also serializable), and that enables you to store the object in a persistence storage medium.
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    3. COthanks for the help
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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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