src/javax/persistence/criteria/From.java

/*******************************************************************************
 * Copyright (c) 2008, 2009 Sun Microsystems. 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 2.0 - Version 2.0 (October 1, 2009)
 *     Specification available from http://jcp.org/en/jsr/detail?id=317
 *
 ******************************************************************************/
package javax.persistence.criteria;

import javax.persistence.metamodel.SingularAttribute;
import javax.persistence.metamodel.CollectionAttribute;
import javax.persistence.metamodel.ListAttribute;
import javax.persistence.metamodel.MapAttribute;
import javax.persistence.metamodel.SetAttribute;
import java.util.Set;

/**
 * Represents a bound type, usually an entity that appears in
 * the from clause, but may also be an embeddable belonging to
 * an entity in the from clause. 
 * <p> Serves as a factory for Joins of associations, embeddables, and 
 * collections belonging to the type, and for Paths of attributes 
 * belonging to the type.
 *
 * @param <Z>  the source type
 * @param <X>  the target type
 *
 * @since Java Persistence 2.0
 */
@SuppressWarnings("hiding")
public interface From<Z, X> extends Path<X>, FetchParent<Z, X> {

    /**
     *  Return the joins that have been made from this bound type.
     *  Returns empty set if no joins have been made from this
     *  bound type.
     *  Modifications to the set do not affect the query.
     *  @return joins made from this type
     */
    Set<Join<X, ?>> getJoins();
	
    /**
     *  Whether the <code>From</code> object has been obtained as a result of
     *  correlation (use of a <code>Subquery</code> <code>correlate</code> 
     *  method).
     *  @return boolean indicating whether the object has been
     *          obtained through correlation
     */
    boolean isCorrelated();

    /**
     *  Returns the parent <code>From</code> object from which the correlated
     *  <code>From</code> object has been obtained through correlation (use
     *  of a <code>Subquery</code> <code>correlate</code> method).
     *  @return  the parent of the correlated From object
     *  @throws IllegalStateException if the From object has
     *          not been obtained through correlation 
     */
    From<Z, X> getCorrelationParent();

    /**
     *  Create an inner join to the specified single-valued 
     *  attribute.
     *  @param attribute  target of the join
     *  @return the resulting join
     */
    <Y> Join<X, Y> join(SingularAttribute<? super X, Y> attribute);

    /**
     *  Create a join to the specified single-valued attribute 
     *  using the given join type.
     *  @param attribute  target of the join
     *  @param jt  join type 
     *  @return the resulting join
     */
    <Y> Join<X, Y> join(SingularAttribute<? super X, Y> attribute, JoinType jt);

    /**
     *  Create an inner join to the specified Collection-valued 
     *  attribute.
     *  @param collection  target of the join
     *  @return the resulting join
     */
    <Y> CollectionJoin<X, Y> join(CollectionAttribute<? super X, Y> collection);

    /**
     *  Create an inner join to the specified Set-valued attribute.
     *  @param set  target of the join
     *  @return the resulting join
     */
    <Y> SetJoin<X, Y> join(SetAttribute<? super X, Y> set);

    /**
     *  Create an inner join to the specified List-valued attribute.
     *  @param list  target of the join
     *  @return the resulting join
     */
    <Y> ListJoin<X, Y> join(ListAttribute<? super X, Y> list);

    /**
     *  Create an inner join to the specified Map-valued attribute.
     *  @param map  target of the join
     *  @return the resulting join
     */
    <K, V> MapJoin<X, K, V> join(MapAttribute<? super X, K, V> map);

    /**
     *  Create a join to the specified Collection-valued attribute 
     *  using the given join type.
     *  @param collection  target of the join
     *  @param jt  join type 
     *  @return the resulting join
     */
    <Y> CollectionJoin<X, Y> join(CollectionAttribute<? super X, Y> collection, JoinType jt);

    /**
     *  Create a join to the specified Set-valued attribute using 
     *  the given join type.
     *  @param set  target of the join
     *  @param jt  join type 
     *  @return the resulting join
     */
    <Y> SetJoin<X, Y> join(SetAttribute<? super X, Y> set, JoinType jt);

    /**
     *  Create a join to the specified List-valued attribute using 
     *  the given join type.
     *  @param list  target of the join
     *  @param jt  join type 
     *  @return the resulting join
     */
    <Y> ListJoin<X, Y> join(ListAttribute<? super X, Y> list, JoinType jt);

    /**
     *  Create a join to the specified Map-valued attribute using 
     *  the given join type.
     *  @param map  target of the join
     *  @param jt  join type 
     *  @return the resulting join
     */
    <K, V> MapJoin<X, K, V> join(MapAttribute<? super X, K, V> map, JoinType jt);

	
    //String-based:

    /**
     *  Create an inner join to the specified attribute.
     *  @param attributeName  name of the attribute for the 
     *               target of the join
     *  @return the resulting join
     *  @throws IllegalArgumentException if attribute of the given
     *          name does not exist
     */
    <X, Y> Join<X, Y> join(String attributeName);	

    /**
     *  Create an inner join to the specified Collection-valued 
     *  attribute.
     *  @param attributeName  name of the attribute for the 
     *               target of the join
     *  @return the resulting join
     *  @throws IllegalArgumentException if attribute of the given
     *          name does not exist
     */
    <X, Y> CollectionJoin<X, Y> joinCollection(String attributeName);	

    /**
     *  Create an inner join to the specified Set-valued attribute.
     *  @param attributeName  name of the attribute for the 
     *               target of the join
     *  @return the resulting join
     *  @throws IllegalArgumentException if attribute of the given
     *          name does not exist
     */
    <X, Y> SetJoin<X, Y> joinSet(String attributeName);	

    /**
     *  Create an inner join to the specified List-valued attribute.
     *  @param attributeName  name of the attribute for the 
     *               target of the join
     *  @return the resulting join
     *  @throws IllegalArgumentException if attribute of the given
     *          name does not exist
     */
    <X, Y> ListJoin<X, Y> joinList(String attributeName);		
    
    /**
     *  Create an inner join to the specified Map-valued attribute.
     *  @param attributeName  name of the attribute for the 
     *               target of the join
     *  @return the resulting join
     *  @throws IllegalArgumentException if attribute of the given
     *          name does not exist
     */
    <X, K, V> MapJoin<X, K, V> joinMap(String attributeName);	

    /**
     *  Create a join to the specified attribute using the given
     *  join type.
     *  @param attributeName  name of the attribute for the 
     *               target of the join
     *  @param jt  join type
     *  @return the resulting join
     *  @throws IllegalArgumentException if attribute of the given
     *          name does not exist
     */
    <X, Y> Join<X, Y> join(String attributeName, JoinType jt);	
    
    /**
     *  Create a join to the specified Collection-valued attribute 
     *  using the given join type.
     *  @param attributeName  name of the attribute for the 
     *               target of the join
     *  @param jt  join type
     *  @return the resulting join
     *  @throws IllegalArgumentException if attribute of the given
     *          name does not exist
     */
    <X, Y> CollectionJoin<X, Y> joinCollection(String attributeName, JoinType jt);	

    /**
     *  Create a join to the specified Set-valued attribute using 
     *  the given join type.
     *  @param attributeName  name of the attribute for the 
     *               target of the join
     *  @param jt  join type
     *  @return the resulting join
     *  @throws IllegalArgumentException if attribute of the given
     *          name does not exist
     */
    <X, Y> SetJoin<X, Y> joinSet(String attributeName, JoinType jt);	

    /**
     *  Create a join to the specified List-valued attribute using 
     *  the given join type.
     *  @param attributeName  name of the attribute for the 
     *               target of the join
     *  @param jt  join type
     *  @return the resulting join
     *  @throws IllegalArgumentException if attribute of the given
     *          name does not exist
     */
    <X, Y> ListJoin<X, Y> joinList(String attributeName, JoinType jt);	

    /**
     *  Create a join to the specified Map-valued attribute using 
     *  the given join type.
     *  @param attributeName  name of the attribute for the 
     *               target of the join
     *  @param jt  join type
     *  @return the resulting join
     *  @throws IllegalArgumentException if attribute of the given
     *          name does not exist
     */
    <X, K, V> MapJoin<X, K, V> joinMap(String attributeName, JoinType jt);	
}