The document summarizes new features in JPA 2.0, including: 1) Standard properties were added to persistence.xml to configure things like locking timeouts and query timeouts. 2) The @AccessType annotation now allows mixed field and property access within an entity, overriding the default at the attribute level. 3) Derived identifiers allow identifiers to be derived from relationships rather than requiring a separate foreign key field. 4) New features were added for collections like @ElementCollection and support for ordering collections with @OrderColumn.

1. JPA 2.0What’s new?Emiel PaasschensRef. implemenatie van EclipseLink is bijlange (met name Criteria API) nanognietaf, dus…GEEN Hands-On of tochwel…

2. Programma Standard properties in persistence.xml

3. Mixed @AccessType

4. Derived Identifiers

5. @ElementCollection

6. Undirectional @OneToMany / @OneToOne

7. @OrderColumn

8. Shared Cache API

9. Locking

10. JP QL

11. Expression and criteria API

12. HandsOn?

13. Drankjeaan de barStandard properties for persistence.xmlSE only:javax.persistence.jdbc.driver fully qualified name of the driver class

14. javax.persistence.jdbc.url driver-specific URL

15. javax.persistence.jdbc.user username used by database connection

16. javax.persistence.jdbc.password password for database connection validation EE and SE:javax.persistence.lock.timeoutvalue in milliseconds for pessimistic lock timeout

17. javax.persistence.query.timeoutvalue in milliseconds for query timeout

18. javax.persistence.validation.group.pre-persist groups that are targeted for validation upon the pre-persist event

19. javax.persistence.validation.group.pre-update groups that are targeted for validation upon the pre-update event

20. javax.persistence.validation.group.pre-remove groups that are targeted for validation upon the pre-remove eventMixed @AccessTypeProperty based or field based:@Access(FIELD)@Access(PROPERTY)

21. Can be mixed now! (instead of one or the other)At Entity/Class level the default Access type is defined

22. Can be set per attribute to differ from default: - on field (declaration) @Access(FIELD) access directly on instance variable by pers.prov.- on property (getter accessor) @Access(PROPERTY) access via accessor methods by pers. prov.

23. Be aware: @Access(PROPERTY):- validation/conversion logic in accessor methods is executed!- exceptions are catched and wrapped in PersistenceException, which is thrown. Transactions are marked for rollback.

24. The access type of an embeddable class is determined by the access type class in which it is embedded, independent of the containing class.Mixed @AccessType(code)@Entity@Access(FIELD)public class Vehicle { @Id private Long id; @Transient double fuelEfficieny; @Access(PROPERTY) @Column(name=”FUEL_EFF”) public double getDbFuelEfficiency(){ return convertToMetric(fuelEfficieny); } public void setDbFuelEfficiency(double d){fuelEfficieny= convertToImperial(d); }}

25. Derived Identifiers (1)Old JPA 1.0 way: Identifiers that include a relationship

26. Require an additional foreign key field

27. Indicate one of the mappings as read only