6 Replies Latest reply on Oct 22, 2007 10:01 PM by norman.richards

    @Out-jection fails to work in certain conditions - Beware!

    gothmog Oct 19, 2007 7:53 AM

      Hi,

      This is an interesting example and I would be grateful if anyone could shed some light on this extremely strange behaviour.

      It seems that in the following example, if an item is an @Entity Pojo on an action class and the entity manager is @In-jected to the same action class (you don't have to use it) then @Out-jection will fail.

      The following simple example will illustrate.

      This simple page will display the value of an item if the item is not null

      <body>
 <f:view>
 <h:form>
 <div><h:commandLink value="New Item" action="#{testPage.newItem}" /></div>
 <s:div rendered="#{testPage.item != null}">
 #{testPage.item.name}
 </s:div>
 <h:commandLink value="Clear Item" action="#{testPage.clearItem}" />
 </h:form>
 </f:view>
</body>


      The testPage action class is as follows 

      @Name("testPage")
@Scope(ScopeType.CONVERSATION)
public class TestPageAction {

 @In EntityManager entityManager;

private Item item;

 public Item getItem() {
 return item;
 }

 public void setItem(Item item) {
 this.item = item;
 }

 @Create
 @Begin(join=true)
 public void newItem() {
 item = new Item();
 item.setName("some item");
 }

 public void clearItem() {
 item = null;
 }
}


      Item is as follows 
      @Entity
public class Item {

 @Id
 @GeneratedValue
 private long id;

 private String name;

 public String getName() {
 return name;
 }

 public void setName(String name) {
 this.name = name;
 }

 public long getId() {
 return id;
 }

 public void setId(long id) {
 this.id = id;
 }
}


      Now this example will fail to remove the item text when you click the Clear Item link and it seems it is because the outjection failed to outject a null value for the item.

      Now the interesting this is if you do ANY of the following the example will work:

      1. Change item to a non @Entity pojo - example works or
      2. Comment out the injection of the EntityManager - example works

      Can anyone shed some light on this? I've spent a lot of time stepping through the seam source and even though after the invoke of the action method the item is set to null it mysteriously gets reset back to a value before outjection occurs.

      Any help would be appreciated

      Thanks

      Troy


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