So for latest plea for help, I have a superclass entity (Animal), and two
subclass entities (Dog, Cat) and an inheritance problem. The problem I have is
in a stateful bean very similar to the example 'Messages' except mine is called
"findAnimalLikeNameBean", and it runs queries on generalized animals. The
problem I have with the following example is that the animal never gets
outjected to the Animal field in my "findAnimalLikeNameBean", Please note the
(//THIS ALWAYS RETURNS NULL") in the last code snippet of this post. I think I
did a pretty good job scouring stuff to see what I did wrong but couldn't find
anything (yet). Are there special cicumstances concerning inheritance and
polymorphism?
| @Entity(name="Animal")
| @Table(name="ag_animal")
| @Inheritance(strategy = InheritanceType.JOINED)
| @Name(value="animal")
| @Scope(value=ScopeType.SESSION)
| public class Animal implements Serializable {
|
| ....
| }
|
| @Entity(name="Cat")
| @Table(name="ag_cat")
| @Inheritance(strategy = InheritanceType.JOINED)
| @Name(value="cat")
| public class Cat extends Animal implements Serializable {
| ....
| }
|
| @Entity(name="Dog")
| @Table(name="ag_dog")
| @Inheritance(strategy = InheritanceType.JOINED)
| @Name(value="dog")
| public class Dog extends Animal implements Serializable {
| ....
| }
|
| @Stateful
| @Name(value="findAnimalsLikeNameBean")
| @Scope(value=ScopeType.SESSION)
| public class FindAnimalsLikeNameBean extends AnimalQueryBean
| implements FindAnimalsLikeNameLocal{
|
| @PersistenceContext(unitName="mypets",
| type=PersistenceContextType.EXTENDED)
| private EntityManager entityManager;
|
| private String name;
|
| public void setName(String name) {
| this.name = name;
| }
|
| public String getName() {
| return name;
| }
|
|
|
| // public void setAnimal(Animal animal) {
| // this.animal = animal;
| // }
| //
| // public Animal getAnimal() {
| // return animal;
| // }
|
| @DataModel
| private List<Animal> animalList;
|
| @DataModelSelection @Out
| private Animal animal;
|
| @Logger
| private Log log;
|
| public void setAnimalList(List<Animal> animalList) {
| this.animalList = animalList;
| }
|
| public List<Animal> getAnimalList() {
| return animalList;
| }
|
| public String execute() {
|
| animalList = findLikeName(getName());
| return "Success";
| }
|
| @TransactionAttribute(value=TransactionAttributeType.REQUIRED)
| public List<Animal> findLikeName(String name) {
| String queryString = "SELECT p FROM Animal p " +
| "WHERE UPPER(p.name) LIKE UPPER(:name)) " +
| "ORDER BY p.name ASC";
| Query query = entityManager.createQuery(queryString);
| query.setParameter("name", '%' + name + '%');
| return createAnimalList(query.getResultList());
| }
|
| public String select() {
| System.out.println(">>" + animal); //THIS ALWAYS RETURNS NULL
| if (animal != null) {
|
| if (animal instanceof Dog {
| return "Dog";
| }
| if (animal instanceof Cat) {
| return "Cat";
| }
| }
| return "Success";
| }
|
| @Remove @Destroy
| public void destroy() {}
| }
|
View the original post :
http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3953893#3953893
Reply to the post :
http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=3953893
Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642
_______________________________________________
JBoss-user mailing list
JBoss-user@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/jboss-user
