javax.persistence.Id - JPA annotation

javax.persistence
Annotation Id

Target:
Fields (including property get methods)
Specifies the primary key of an entity. The field or property to which the Id annotation is applied should be one of the following types: any Java primitive type; any primitive wrapper type; String; java.util.Date; java.sql.Date; java.math.BigDecimal; java.math.BigInteger.

The mapped column for the primary key of the entity is assumed to be the primary key of the primary table. If no Column annotation is specified, the primary key column name is assumed to be the name of the primary key property or field.

Example:


   @Id
   public Long getId() { return id; }
Since:
JPA 1.0
See Also:
Column
GeneratedValue
Learn how to define and use ID fields in Chapter 2 of the ObjectDB/JPA manual.
This annotation is a marker annotation (with no elements).