JEE5 Sample
Download NetBeans Projekt
JSF
Injection eines EJBs im WebLayer:
@EJB(name="QuestionBCBean") QuestionBCLocal bc;
EJB3
Injection vom EntityManager in einem EJB:
@PersistenceContext(unitName="WebLearingPlatformEAR-ejbPU") protected EntityManager em;
JPA
Bikirektionale One To Many Beziehung
In der Klasse Question.java
@OneToMany(mappedBy="question", cascade = {CascadeType.PERSIST, CascadeType.MERGE} )
private List<QuestionOption> options = new ArrayList<QuestionOption>();
In der Klasse QuestionOption.java
@ManyToOne(optional=false, fetch = FetchType.EAGER)
@JoinColumn(name="questionid", nullable=false)
private Question question;