ID mapping


Use an ID Mapping to specify the primary key of an entity. ID mappings may be used with a Persistent entity or Mapped superclass.

  1. In the Persistence Outline view, select the field to map. The Persistence Properties view (for attributes) displays the properties for the selected.

  2. In the Map As field, select ID.

  3. Use this table to complete the remaining fields on the Persistence Properties view.

    Property Description Default
    Map As Defines this mapping as an ID Mapping. ID
    Columns The database column (and its table) mapped to the entity attribute. See "Column" for details.
    • Name – Name of the database column.

    • Table – Name of the database table.

    By default, the Column is assumed to be named identically to the attribute.
    Temporal Specifies the type of data. See "Temporal" for details.
    • Date

    • Time

    • Timestamp


    Generated Value These fields define how the primary key is generated.
      Strategy See "Generated Value" for details.
    • Auto

    • Sequence

    • Identity

    • Table

    None (no generated value)
      Generator Name Name of the primary key generator specified in the Strategy

Additional fields will appear on the General tab, depending on the selected Strategy. See "Persistence Properties view (for attributes)" for additional information.

Eclipse adds the following annotations to the field:

@Id
@Column(name="<COLUMN>")
@GeneratedValue(strategy=GeneratorType.<STRATEGY>, generator = "<GENERATOR_NAME>")
	@Temporal(TemporalType.<TEMPORAL>)

 

Related task

Mapping an entity

 

Related reference

Persistence Outline view
Persistence Properties view (for attributes)

 

Related concept

Understanding OR mappings
Understanding JSR220: EJB 3.0