Package jakarta.persistence

Annotation Interface MapsId

@Target({METHOD,FIELD}) @Retention(RUNTIME) public @interface MapsId
Designates a 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 primary key of the entity is of the same Java type as the primary key of the entity referenced by the relationship, the value attribute is not specified.

In this example, the parent entity has simple primary key:

And then the dependent entity uses EmbeddedId to declare its composite primary key:

If a ManyToOne or OneToOne relationship declared by a dependent entity is annotated MapsId, an instance of the entity cannot be made persistent until the relationship has been assigned a reference to an instance of the parent entity, since the identity of the dependent entity declaring the relationship is derived from the referenced parent entity.

Since:
2.0

  • Optional Element Summary

    Optional Elements
    Modifier and Type
    Optional Element
    Description
    String
    value
    (Optional) The name of the attribute within the composite key to which the relationship attribute corresponds.

  • Element Details

    • value

      String value
      (Optional) The name of the attribute within the composite key to which the relationship attribute corresponds. If not explicitly specified, the relationship maps the primary key of the entity.
      Default:
      ""