Use a Many-to-One mapping to defines a single-valued association to another entity class that has many-to-one multiplicity.
In the JPA Structure view, select the field to map.
Right click the field and then select Map As > Many-to-One. The JPA Details view (for attributes) displays the properties for the selected.
Use this table to complete the General information fields JPA Details view.
Property | Description | Default |
---|---|---|
Mapping Entity Hyperlink | Defines mapping as Many-to-One. This corresponds to the @ManyToOne annotation. |
Many-to-One |
Target Entity | The entity to which this attribute is mapped. | null
You do not need to explicitly specify the target entity, since it can be inferred from the type of object being referenced. |
Fetch | Defines how data is loaded from the database. See "Fetch Type" for details.
|
Eager |
Cascade | See "Cascade Type" for details.
|
Default |
Optional | Specifies if this field is can be null. | Yes |
Use this table to complete the fields on the Join Columns Information tab in the JPA Details view.
Eclipse adds the following annotations to the field:
@JoinTable(joinColumns=@JoinColumn(name="<JOIN_COLUMN>"), name = "<JOIN_TABLE_NAME>") @ManyToOne(targetEntity=<TARGET_ENTITY>, fetch=<FETCH_TYPE>, cascade=<CASCADE_TYPE>)