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@Target(value=TYPE) @Retention(value=RUNTIME) public @interface DiscriminatorValue
Is used to specify the value of the discriminator column for
entities of the given type. The DiscriminatorValue
annotation can only be specified on a concrete entity
class. If the DiscriminatorValue
annotation is not
specified and a discriminator column is used, a provider-specific
function will be used to generate a value representing the
entity type. If the DiscriminatorType
is STRING
, the discriminator value
default is the entity name.
The inheritance strategy and the discriminator column are only specified in the root of an entity class hierarchy or subhierarchy in which a different inheritance strategy is applied. The discriminator value, if not defaulted, should be specified for each entity class in the hierarchy.
Example: @Entity @Table(name="CUST") @Inheritance(strategy=SINGLE_TABLE) @DiscriminatorColumn(name="DISC", discriminatorType=STRING,length=20) @DiscriminatorValue("CUSTOMER") public class Customer { ... } @Entity @DiscriminatorValue("VCUSTOMER") public class ValuedCustomer extends Customer { ... }
Required Element Summary | |
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String |
value
(Optional) The value that indicates that the row is an entity of the annotated entity type. |
Element Detail |
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public abstract String value
If the DiscriminatorValue
annotation is not
specified and a discriminator column is used, a provider-specific
function will be used to generate a value representing the
entity type. If the DiscriminatorType is STRING
, the discriminator value
default is the entity name.
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SUMMARY: REQUIRED | OPTIONAL | DETAIL: ELEMENT |
Copyright 2006 Sun Microsystems, Inc. All rights reserved.