hibernate级联案例.docxVIP

目标：级联删除配置场景：在一片辽阔的土地上进行播种，各种各样的小树苗生枝散叶，形成茂密的森林。一天来了一群伐木者。他们各自在随机树上做了标记，准备开始工作。他们工作之余，摘树叶打发时间。一段时间后，工作完成了，他们收拾行囊离开。他们顺便带走了茂密的森林，只剩下无数的落叶。类图：类清单：Forest/* * Copyright (c) 2008-2012 by DHCC * All rights reserved. */package com.dhcc.itsm.caze.cascade.model;import java.util.HashSet;import java.util.Set;import javax.persistence.CascadeType;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.FetchType;import javax.persistence.JoinColumn;import javax.persistence.OneToMany;import javax.persistence.Table;import com.dhcc.core.entity.IdentifiableEntity;/** * Forest.java * * * @author Sixday 2010-4-20 * @version * @modify */@Entity@Table(name = ITSM_CAZE_FOREST)public class Forest extends IdentifiableEntity {String name;@Columnpublic String getName() {return name;}public void setName(String name) {this.name = name;}SetTree tree;@OneToMany(cascade = { CascadeType.REMOVE }, fetch = FetchType.LAZY)@JoinColumn(name = forest)public SetTree getTree() {if (null == tree) {tree = new HashSetTree();}return tree;}public void setTree(SetTree tree) {this.tree = tree;}}Tree/* * Copyright (c) 2008-2012 by DHCC * All rights reserved. */package com.dhcc.itsm.caze.cascade.model;import java.util.HashSet;import java.util.Set;import javax.persistence.CascadeType;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.FetchType;import javax.persistence.JoinColumn;import javax.persistence.JoinTable;import javax.persistence.ManyToMany;import javax.persistence.ManyToOne;import javax.persistence.OneToMany;import javax.persistence.Table;import com.dhcc.core.entity.IdentifiableEntity;/** * Tree.java * * * @author Sixday 2010-4-20 * @version * @modify */@Entity@Table(name = ITSM_CAZE_TREE)public class Tree extends IdentifiableEntity {Forest forest;SetTreeNode treeNodes;String name;SetWoodcutter woodcutters;@ManyToMany(fetch = FetchType.LAZY,cascade = { CascadeType.REMOVE })@JoinTable(name = ITSM_CAZE_WOODCUTTER_TREE, joinColumns = { @J