hibernate基于主键的双向多对多的关联映射

1、类Role 和Function类Fole:public class Role {private int id;private String name;private Set<Function> functions = new HashSet<Function>(0);//get…set}  Function:  public class Function {private int id;private String name;private String code;private String url;private Set<Role> roles = new HashSet<Role>(0);public Function() {// TODO Auto-generated constructor stub}public Function(String name, String code, String url) {super();this.name = name;this.code = code;this.url = url;}//get…set }2、映射文件Role.hbm.xml<hibernate-mapping package="cn.siggy.pojo"><class name="Role"><id name="id"><generator class="native"></generator></id><property name="name"/><!-- 多对多 --><set name="functions" table="role_func" cascade="save-update"><!-- 表示当前类 映射到关系表中的列--><key column="rid"/><!-- 所对应的另一方在关系表中的列 --><many-to-many column="fid" class="Function"/></set></class></hibernate-mapping>function.hbm.xml  <hibernate-mapping package="cn.siggy.pojo"><class name="Function"><id name="id"><!-- foreign表示引用外键 --><generator class="native"/></id><property name="name"/><property name="code"/><property name="url"/><set name="roles" table="role_func" inverse="true"><key column="fid"/><many-to-many column="rid" class="Role"/></set></class></hibernate-mapping>3、测试代码@Testpublic void testSave() throws HibernateException, SerialException, SQLException{Session session = null;Transaction tx = null;try{session = HibernateUtil.getSession();tx = session.beginTransaction();Function f1 = new Function("用户管理","user_mag","userAction");Function f2 = new Function("角色管理","role_mag","roleAction");Function f3 = new Function("系统管理","sys_mag","sysAction");Function f4 = new Function("权限管理","prev_mag","prevAction");Role r1 = new Role();r1.setName("admin");r1.getFunctions().add(f1);r1.getFunctions().add(f2);r1.getFunctions().add(f3);r1.getFunctions().add(f4);Role r2 = new Role();r2.setName("vip");r2.getFunctions().add(f1);r2.getFunctions().add(f2);session.save(r1);session.save(r2);tx.commit();}catch (HibernateException e) {if(tx!=null)tx.rollback();e.printStackTrace();throw e;}finally{HibernateUtil.closeSession();}}@Testpublic void testGet(){Session session = null;Transaction tx = null;try{session = HibernateUtil.getSession();tx = session.beginTransaction();Role role = (Role)session.get(Role.class, 1);System.out.println("角色名："+role.getName());System.out.println("该角色所对应的权限：");for(Iterator<Function> iter = role.getFunctions().iterator();iter.hasNext();){Function func = iter.next();System.out.println(func.getName()+"---"+func.getCode());}//取数据tx.commit();}catch (HibernateException e) {if(tx!=null)tx.rollback();e.printStackTrace();throw e;}finally{HibernateUtil.closeSession();}}