foreignkeydirection.java

来自「用Java实现的23个常用设计模式源代码」· Java 代码 · 共 36 行

//$Id: ForeignKeyDirection.java,v 1.1.2.2 2003/11/21 16:06:40 oneovthafew Exp $
package net.sf.hibernate.type;

import java.io.Serializable;

import net.sf.hibernate.engine.Cascades;

/**
 * Represents directionality of the foreign key constraint
 * @author Gavin King
 */
public abstract class ForeignKeyDirection implements Serializable {
	protected ForeignKeyDirection() {}
	/**
	 * Should we cascade at this cascade point?
	 * @see net.sf.hibernate.engine.Cascades
	 */
	public abstract boolean cascadeNow(int cascadePoint);

	/**
	 * A foreign key from child to parent
	 */
	public static final ForeignKeyDirection FOREIGN_KEY_TO_PARENT = new ForeignKeyDirection() {
		public boolean cascadeNow(int cascadePoint) {
			return cascadePoint!=Cascades.CASCADE_BEFORE_INSERT_AFTER_DELETE;
		}
	};
	/**
	 * A foreign key from parent to child
	 */
	public static final ForeignKeyDirection FOREIGN_KEY_FROM_PARENT = new ForeignKeyDirection() {
		public boolean cascadeNow(int cascadePoint) {
			return cascadePoint!=Cascades.CASCADE_AFTER_INSERT_BEFORE_DELETE;
		}
	};
}