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EntityResult (Java EE 5 SDK) - Java Platform, Enterprise Edition v5.0 API Specifications

Java EE 5 SDK

javax.persistence
Annotation Type EntityResult


@Target(value={})
@Retention(value=RUNTIME)
public @interface EntityResult

References an entity in the SELECT clause of a SQL query. If this annotation is used, the SQL statement should select all of the columns that are mapped to the entity object. This should include foreign key columns to related entities. The results obtained when insufficient data is available are undefined.

   Example
   Query q = em.createNativeQuery(
       "SELECT o.id, o.quantity, o.item, i.id, i.name, i.description "+
           "FROM Order o, Item i " +
           "WHERE (o.quantity > 25) AND (o.item = i.id)",
       "OrderItemResults");
   @SqlResultSetMapping(name="OrderItemResults",
       entities={
           @EntityResult(entityClass=com.acme.Order.class),
           @EntityResult(entityClass=com.acme.Item.class)
   })
 

Since:
Java Persistence 1.0

Required Element Summary
 Class entityClass
          The class of the result
 
Optional Element Summary
 String discriminatorColumn
          Specifies the column name (or alias) of the column in the SELECT list that is used to determine the type of the entity instance.
 FieldResult[] fields
          Maps the columns specified in the SELECT list of the query to the properties or fields of the entity class.
 

Element Detail

entityClass

public abstract Class entityClass
The class of the result

fields

public abstract FieldResult[] fields
Maps the columns specified in the SELECT list of the query to the properties or fields of the entity class.

Default:
{}

discriminatorColumn

public abstract String discriminatorColumn
Specifies the column name (or alias) of the column in the SELECT list that is used to determine the type of the entity instance.

Default:
""

Java EE 5 SDK

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