svn commit: r581286 - /myfaces/orchestra/trunk/core/src/site/xdoc/persistence.xml

[sk...@apache.org]

Author: skitching
Date: Tue Oct  2 08:51:32 2007
New Revision: 581286

URL: http://svn.apache.org/viewvc?rev=581286&view=rev
Log:
Add some info about persistence.

Modified:
    myfaces/orchestra/trunk/core/src/site/xdoc/persistence.xml

Modified: myfaces/orchestra/trunk/core/src/site/xdoc/persistence.xml
URL: http://svn.apache.org/viewvc/myfaces/orchestra/trunk/core/src/site/xdoc/persistence.xml?rev=581286&r1=581285&r2=581286&view=diff
==============================================================================
--- myfaces/orchestra/trunk/core/src/site/xdoc/persistence.xml (original)
+++ myfaces/orchestra/trunk/core/src/site/xdoc/persistence.xml Tue Oct  2 08:51:32 2007
@@ -204,10 +204,34 @@
 		</section>
 
 		<section name="How to Use Orchestra Conversation Scoped Persistence">
-			<p>TODO: write this section</p>
+			<p>When configured appropriately, Spring will automatically scan the beans
+			it loads for the standard persistence annotations, and injects a persistence
+			context where requested by the bean. Orchestra ensures that the persistence
+			context Spring injects is the appropriate one for the current conversation.</p>
+			<p>Your code is therefore simply straightforward:<pre>
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+public class ComponentDAO
+{
+	@PersistenceContext
+	private EntityManager entityManager;
+	....
+}
+			</pre></p>
+			<p>Spring's annotation support does require, however, that the class containing
+			the annotation be declared as a Spring bean, and instantiated via Spring. This 
+			means that all code which uses an instance of the above class needs to have it
+			injected, rather than using the new() operator to create the instance. Existing
+			code therefore may need to be restructured to take advantage of persistence
+			annotations with Orchestra. The persistence context object that Spring injects
+			is actually a proxy which looks up the correct EntityManager object to use
+			on each method call, so it is safe to use singleton scope (Spring's default
+			scope). Of course if the class has any other non-static members then the
+			scope should be set to "prototype", to avoid conflicts between different
+			instances of this class in different conversations.</p>
 		</section>
 
-		<section name="Documenation Still TODO">
+		<section name="Documentation Still TODO">
 			<p>TODO: document Orchestra's transaction support features</p>
 			<p>TODO: is the persistence-context serializable? Are all persistent objects
 				in the context always serializable?</p>