javax.persistence
Annotation Type MapKey

@Target(value={METHOD,FIELD})
@Retention(value=RUNTIME)
public @interface MapKey

The MapKey annotation is used to specify the map key for associations of type java.util.Map.

Since:

JPA 1.0 version.

Author:

Florent Benoit

See Also:

JPA 2.0 specification

Optional Element Summary

String

name The name element designates the name of the persistent field or property of the associated entity that is used as the map key.

name

public abstract String name

The name element designates the name of the persistent field or property of the associated entity that is used as the map key. If the name element is not specified, the primary key of the associated entity is used as the map key. If the primary key is a composite primary key and is mapped as IdClass, an instance of the primary key class is used as the key.

Default:

""