org.hibernate.FetchMode Maven / Gradle / Ivy
/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
* indicated by the @author tags or express copyright attribution
* statements applied by the authors. All third-party contributions are
* distributed under license by Red Hat Middleware LLC.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*
*/
package org.hibernate;
import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;
/**
* Represents an association fetching strategy. This is used
* together with the Criteria API to specify runtime
* fetching strategies.
*
* For HQL queries, use the FETCH keyword instead.
*
* @see Criteria#setFetchMode(java.lang.String, FetchMode)
* @author Gavin King
*/
public final class FetchMode implements Serializable {
private final String name;
private static final Map INSTANCES = new HashMap();
private FetchMode(String name) {
this.name=name;
}
public String toString() {
return name;
}
/**
* Default to the setting configured in the mapping file.
*/
public static final FetchMode DEFAULT = new FetchMode("DEFAULT");
/**
* Fetch using an outer join. Equivalent to fetch="join".
*/
public static final FetchMode JOIN = new FetchMode("JOIN");
/**
* Fetch eagerly, using a separate select. Equivalent to
* fetch="select".
*/
public static final FetchMode SELECT = new FetchMode("SELECT");
/**
* Fetch lazily. Equivalent to outer-join="false".
* @deprecated use FetchMode.SELECT
*/
public static final FetchMode LAZY = SELECT;
/**
* Fetch eagerly, using an outer join. Equivalent to
* outer-join="true".
* @deprecated use FetchMode.JOIN
*/
public static final FetchMode EAGER = JOIN;
static {
INSTANCES.put( JOIN.name, JOIN );
INSTANCES.put( SELECT.name, SELECT );
INSTANCES.put( DEFAULT.name, DEFAULT );
}
private Object readResolve() {
return INSTANCES.get(name);
}
}