//$Id: CriteriaSpecification.java 9116 2006-01-23 21:21:01Z steveebersole $
package org.hibernate.criterion;

import org.hibernate.transform.AliasToEntityMapResultTransformer;
import org.hibernate.transform.DistinctRootEntityResultTransformer;
import org.hibernate.transform.PassThroughResultTransformer;
import org.hibernate.transform.ResultTransformer;
import org.hibernate.transform.RootEntityResultTransformer;

/**
 * @author Gavin King
 */
public interface CriteriaSpecification {

	/**
	 * The alias that refers to the "root" entity of the criteria query.
	 */
	public static final String ROOT_ALIAS = "this";

	/**
	 * Each row of results is a <tt>Map</tt> from alias to entity instance
	 */
	public static final ResultTransformer ALIAS_TO_ENTITY_MAP = new AliasToEntityMapResultTransformer();

	/**
	 * Each row of results is an instance of the root entity
	 */
	public static final ResultTransformer ROOT_ENTITY = new RootEntityResultTransformer();

	/**
	 * Each row of results is a distinct instance of the root entity
	 */
	public static final ResultTransformer DISTINCT_ROOT_ENTITY = new DistinctRootEntityResultTransformer();

	/**
	 * This result transformer is selected implicitly by calling <tt>setProjection()</tt>
	 */
	public static final ResultTransformer PROJECTION = new PassThroughResultTransformer();

	/**
	 * Specifies joining to an entity based on an inner join.
	 */
	public static final int INNER_JOIN = org.hibernate.sql.JoinFragment.INNER_JOIN;

	/**
	 * Specifies joining to an entity based on a full join.
	 */
	public static final int FULL_JOIN = org.hibernate.sql.JoinFragment.FULL_JOIN;

	/**
	 * Specifies joining to an entity based on a left outer join.
	 */
	public static final int LEFT_JOIN = org.hibernate.sql.JoinFragment.LEFT_OUTER_JOIN;
	
}