javax.persistence.EntityResult Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2008 - 2013 Oracle Corporation. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* Linda DeMichiel - Java Persistence 2.1
* Linda DeMichiel - Java Persistence 2.0
*
******************************************************************************/
package javax.persistence;
import java.lang.annotation.Target;
import java.lang.annotation.Retention;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
/**
* Used in conjunction with the {@link SqlResultSetMapping} annotation to map the SELECT
* clause of a SQL query to an entity result.
*
* 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)
* })
*
*
* @see SqlResultSetMapping
*
* @since Java Persistence 1.0
*/
@Target({})
@Retention(RUNTIME)
public @interface EntityResult {
/** The class of the result. */
Class entityClass();
/**
* Maps the columns specified in the SELECT list of the
* query to the properties or fields of the entity class.
*/
FieldResult[] fields() default {};
/**
* Specifies the column name (or alias) of the column in
* the SELECT list that is used to determine the type of
* the entity instance.
*/
String discriminatorColumn() default "";
}