Is the statement about EJB 3.x right?

[Yingjie Liu]

Dear All,

a transaction management type can not be specified for ejb 3.x entiites?

but I think it can, I make a test on glass fish, my test structure

servlet--> statefull bean--> entity can be successfully run. the city data can be inserted in to the database.

@Entity
@TransactionManagement(TransactionManagementType.BEAN)
public class City implements Serializable {

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
    private String name;
    private String country;
    private long population;

    public City() {
    }

    public City(String name, String country, long population) {
        this.name = name;
        this.country = country;
        this.population = population;
    }

    public String getCountry() {
        return country;
    }

    public void setCountry(String country) {
        this.country = country;
    }

    public String getName() {
        return name;
    }

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

    public long getPopulation() {
        return population;
    }

    public void setPopulation(long population) {
        this.population = population;
    }

    public Long getId() {
        return id;
    }

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

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (id != null ? id.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {
        // TODO: Warning - this method won't work in the case the id fields are not set
        if (!(object instanceof City)) {
            return false;
        }
        City other = (City) object;
        if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "packt.City[ id=" + id + " ]";
    }
}

[Edit - added code tags = MB]

[Hebert Coelho]

I believe that EJB will ignore this annotation on an entity. @TransactionManagement(TransactionManagementType.BEAN)

[Ivan Krizsan]

Hi!
EJB 3.x entities are, as far as I understand, classes annotated with JPA annotations.
In a Java EE environment, entities are usually manipulated by EJBs or other components, for which transaction management is specified.
Note that because you have managed to create an example program that runs on GlassFish does not mean anything - there are cases when GlassFish allows certain behaviour that does not adhere to EJB 3.1 specifications.
Reference: Section 13.3.6 EJB 3.1 specification.
Best wishes!

[Yingjie Liu]

Hi,

Thanks for your reply, I checked the specification and there is another statement on the specification I do not understand

" The transaction management type of a bean is determined by the Bean Provider. The application assembler
is not permitted to use the deployment descriptor to override a bean’s transaction management type regardless of whether it has
been explicitly specified or defaulted by the Bean Provider. "

Does that mean application assembler can not use the 'transaction-type' to perform the overriding?


Thanks,
Yingjie

[Ivan Krizsan]

Hi!

Yingjie Liu wrote:
Does that mean application assembler can not use the 'transaction-type' to perform the overriding?

Exactly.
If you think about it, changing the transaction type from BEAN to CONTAINER may render an EJB useless - any calls related to the object implementing UserTransaction would suddenly fail with system exceptions.
The transaction type is closely coupled to the code of the EJB class.
Best wishes!

[Yingjie Liu]

Got it, Thank you very much!