org.hibernate.FetchMode Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of hibernate Show documentation

Relational Persistence for Java

There is a newer version: 3.6.0.Beta2

//$Id: FetchMode.java 5060 2004-12-24 03:11:05Z oneovthafew $
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);
	}

}