@Target(value={METHOD,FIELD})
@Retention(value=RUNTIME)
public @interface MapKeyColumn
name
element is not specified, it
defaults to the concatenation of the following: the name of the
referencing relationship field or property; "_"; "KEY".
Example: @Entity public class Item { @Id int id; ... @ElementCollection @MapKeyColumn(name="IMAGE_NAME") @Column(name="IMAGE_FILENAME") @CollectionTable(name="IMAGE_MAPPING") Map<String, String> images; // map from image name to filename ... }
Modifier and Type | Optional Element and Description |
---|---|
java.lang.String |
columnDefinition
(Optional) The SQL fragment that is used when generating the DDL for the
column.
|
boolean |
insertable
(Optional) Whether the column is included in SQL INSERT statements
generated by the persistence provider.
|
int |
length
(Optional) The column length.
|
java.lang.String |
name
(Optional) The name of the map key column.
|
boolean |
nullable
(Optional) Whether the database column is nullable.
|
int |
precision
(Optional) The precision for a decimal (exact numeric) column.
|
int |
scale
(Optional) The scale for a decimal (exact numeric) column.
|
java.lang.String |
table
(Optional) The name of the table that contains the column.
|
boolean |
unique
(Optional) Whether the column is a unique key.
|
boolean |
updatable
(Optional) Whether the column is included in SQL UPDATE statements
generated by the persistence provider.
|
public abstract java.lang.String name
Defaults to the concatenation of the following: the name of
the referencing relationship field or property; "_"; "KEY
".
public abstract boolean unique
UniqueConstraint
annotation
at the table level and is useful for when the unique key
constraint corresponds to only a single column. This
constraint applies in addition to any constraint entailed
by primary key mapping and to constraints specified at the
table level.public abstract boolean nullable
public abstract boolean insertable
public abstract boolean updatable
public abstract java.lang.String columnDefinition
Defaults to the generated SQL to create a column of the inferred type.
public abstract java.lang.String table
Defaults: If the map key is for an element collection, the name of the collection table for the map value. If the map key is for a OneToMany or ManyToMany entity relationship using a join table, the name of the join table for the map. If the map key is for a OneToMany entity relationship using a foreign key mapping strategy, the name of the primary table of the entity that is the value of the map.
public abstract int length
public abstract int precision
Default: 0. (The value must be set by the developer.)
public abstract int scale