Hibernate example source code file (CascadeStyle.java)

This example Hibernate source code file (CascadeStyle.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Hibernate tags/keywords

all, cascadestyle, cascadestyle, delete, delete, evict, io, lock, lock, persist, refresh, replicate, string, string, update, util

The Hibernate CascadeStyle.java source code

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2008-2011, Red Hat Inc. 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 Inc.
 *
 * 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.engine.spi;

import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;

import org.hibernate.MappingException;
import org.hibernate.internal.util.collections.ArrayHelper;

/**
 * A contract for defining the aspects of cascading various persistence actions.
 *
 * @author Gavin King
 * @see CascadingAction
 */
public abstract class CascadeStyle implements Serializable {

	/**
	 * For this style, should the given action be cascaded?
	 *
	 * @param action The action to be checked for cascade-ability.
	 *
	 * @return True if the action should be cascaded under this style; false otherwise.
	 */
	public abstract boolean doCascade(CascadingAction action);

	/**
	 * Probably more aptly named something like doCascadeToCollectionElements(); it is
	 * however used from both the collection and to-one logic branches...
	 * <p/>
	 * For this style, should the given action really be cascaded?  The default
	 * implementation is simply to return {@link #doCascade}; for certain
	 * styles (currently only delete-orphan), however, we need to be able to
	 * control this separately.
	 *
	 * @param action The action to be checked for cascade-ability.
	 *
	 * @return True if the action should be really cascaded under this style;
	 *         false otherwise.
	 */
	public boolean reallyDoCascade(CascadingAction action) {
		return doCascade( action );
	}

	/**
	 * Do we need to delete orphaned collection elements?
	 *
	 * @return True if this style need to account for orphan delete
	 *         operations; false otherwise.
	 */
	public boolean hasOrphanDelete() {
		return false;
	}

	public static final class MultipleCascadeStyle extends CascadeStyle {
		private final CascadeStyle[] styles;

		public MultipleCascadeStyle(CascadeStyle[] styles) {
			this.styles = styles;
		}

		public boolean doCascade(CascadingAction action) {
			for ( CascadeStyle style : styles ) {
				if ( style.doCascade( action ) ) {
					return true;
				}
			}
			return false;
		}

		public boolean reallyDoCascade(CascadingAction action) {
			for ( CascadeStyle style : styles ) {
				if ( style.reallyDoCascade( action ) ) {
					return true;
				}
			}
			return false;
		}

		public boolean hasOrphanDelete() {
			for ( CascadeStyle style : styles ) {
				if ( style.hasOrphanDelete() ) {
					return true;
				}
			}
			return false;
		}

		public String toString() {
			return ArrayHelper.toString( styles );
		}
	}

	/**
	 * save / delete / update / evict / lock / replicate / merge / persist + delete orphans
	 */
	public static final CascadeStyle ALL_DELETE_ORPHAN = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return true;
		}

		public boolean hasOrphanDelete() {
			return true;
		}

		public String toString() {
			return "STYLE_ALL_DELETE_ORPHAN";
		}
	};

	/**
	 * save / delete / update / evict / lock / replicate / merge / persist
	 */
	public static final CascadeStyle ALL = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return true;
		}

		public String toString() {
			return "STYLE_ALL";
		}
	};

	/**
	 * save / update
	 */
	public static final CascadeStyle UPDATE = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return action == CascadingAction.SAVE_UPDATE;
		}

		public String toString() {
			return "STYLE_SAVE_UPDATE";
		}
	};

	/**
	 * lock
	 */
	public static final CascadeStyle LOCK = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return action == CascadingAction.LOCK;
		}

		public String toString() {
			return "STYLE_LOCK";
		}
	};

	/**
	 * refresh
	 */
	public static final CascadeStyle REFRESH = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return action == CascadingAction.REFRESH;
		}

		public String toString() {
			return "STYLE_REFRESH";
		}
	};

	/**
	 * evict
	 */
	public static final CascadeStyle EVICT = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return action == CascadingAction.EVICT;
		}

		public String toString() {
			return "STYLE_EVICT";
		}
	};

	/**
	 * replicate
	 */
	public static final CascadeStyle REPLICATE = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return action == CascadingAction.REPLICATE;
		}

		public String toString() {
			return "STYLE_REPLICATE";
		}
	};
	/**
	 * merge
	 */
	public static final CascadeStyle MERGE = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return action == CascadingAction.MERGE;
		}

		public String toString() {
			return "STYLE_MERGE";
		}
	};

	/**
	 * create
	 */
	public static final CascadeStyle PERSIST = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return action == CascadingAction.PERSIST
					|| action == CascadingAction.PERSIST_ON_FLUSH;
		}

		public String toString() {
			return "STYLE_PERSIST";
		}
	};

	/**
	 * delete
	 */
	public static final CascadeStyle DELETE = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return action == CascadingAction.DELETE;
		}

		public String toString() {
			return "STYLE_DELETE";
		}
	};

	/**
	 * delete + delete orphans
	 */
	public static final CascadeStyle DELETE_ORPHAN = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return action == CascadingAction.DELETE || action == CascadingAction.SAVE_UPDATE;
		}

		public boolean reallyDoCascade(CascadingAction action) {
			return action == CascadingAction.DELETE;
		}

		public boolean hasOrphanDelete() {
			return true;
		}

		public String toString() {
			return "STYLE_DELETE_ORPHAN";
		}
	};

	/**
	 * no cascades
	 */
	public static final CascadeStyle NONE = new CascadeStyle() {
		public boolean doCascade(CascadingAction action) {
			return false;
		}

		public String toString() {
			return "STYLE_NONE";
		}
	};

	public CascadeStyle() {
	}

	static final Map<String, CascadeStyle> STYLES = new HashMap();

	static {
		STYLES.put( "all", ALL );
		STYLES.put( "all-delete-orphan", ALL_DELETE_ORPHAN );
		STYLES.put( "save-update", UPDATE );
		STYLES.put( "persist", PERSIST );
		STYLES.put( "merge", MERGE );
		STYLES.put( "lock", LOCK );
		STYLES.put( "refresh", REFRESH );
		STYLES.put( "replicate", REPLICATE );
		STYLES.put( "evict", EVICT );
		STYLES.put( "delete", DELETE );
		STYLES.put( "remove", DELETE ); // adds remove as a sort-of alias for delete...
		STYLES.put( "delete-orphan", DELETE_ORPHAN );
		STYLES.put( "none", NONE );
	}

	/**
	 * Factory method for obtaining named cascade styles
	 *
	 * @param cascade The named cascade style name.
	 *
	 * @return The appropriate CascadeStyle
	 */
	public static CascadeStyle getCascadeStyle(String cascade) {
		CascadeStyle style = STYLES.get( cascade );
		if ( style == null ) {
			throw new MappingException( "Unsupported cascade style: " + cascade );
		}
		else {
			return style;
		}
	}
}