@Target(value={METHOD,FIELD}) @Retention(value=RUNTIME) public @interface MapsId
ManyToOne
or OneToOne
relationship attribute that provides the
mapping for an EmbeddedId
primary key, an attribute within an EmbeddedId
primary key,
or a simple primary key of the parent entity. The value
element specifies the attribute within
a composite key to which the relationship attribute corresponds. If the entity's primary key is of the same
Java type as the primary key of the entity referenced by the relationship, the value attribute is not
specified.
Example: // parent entity has simple primary key @Entity public class Employee { @Id long empId; String name; ... } // dependent entity uses EmbeddedId for composite key @Embeddable public class DependentId { String name; long empid; // corresponds to primary key type of Employee } @Entity public class Dependent { @EmbeddedId DependentId id; ... @MapsId("empid") // maps the empid attribute of embedded id @ManyToOne Employee emp; }
public abstract String value
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