beans.xml配置

<?xml version="1.0" encoding="UTF-8"?><!-- 基于注解方式 http://ehcache-spring-annotations.googlecode.com/svn/schema/ehcache-spring 	http://ehcache-spring-annotations.googlecode.com/svn/schema/ehcache-spring/ehcache-spring-1.1.xsd --><beans xmlns="http://www.springframework.org/schema/beans"	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"	xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"	xsi:schemaLocation="http://www.springframework.org/schema/beans           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd           http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd           http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd           http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd           http://ehcache-spring-annotations.googlecode.com/svn/schema/ehcache-spring     		   http://ehcache-spring-annotations.googlecode.com/svn/schema/ehcache-spring/ehcache-spring-1.1.xsd">	<context:annotation-config />	<context:component-scan base-package="com.entity"></context:component-scan>	<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"		destroy-method="close">		<property name="driverClassName" value=http://www.mamicode.com/"oracle.jdbc.driver.OracleDriver" />>

2.Entity(Address)
package com.entity.many2many.bean;import java.util.Set;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.Id;import javax.persistence.ManyToMany;import javax.persistence.Table;import org.hibernate.annotations.GenericGenerator;import org.hibernate.annotations.Parameter;@Entity@Table(name = "addresses")public class Address {	private int id;	private String addressLine;	private String country;	private String postCode;	private Set<Customer> customers;	@Id	@GenericGenerator(name = "GenericGenerator", strategy = "sequence",	parameters = { @Parameter(value = http://www.mamicode.com/"seq_address", name = "sequence") })>

3.Entity(Customer)
package com.entity.many2many.bean;import java.util.Collection;import java.util.Set;import javax.persistence.CascadeType;import javax.persistence.Entity;import javax.persistence.FetchType;import javax.persistence.GeneratedValue;import javax.persistence.Id;import javax.persistence.JoinColumn;import javax.persistence.JoinTable;import javax.persistence.ManyToMany;import javax.persistence.Table;import org.hibernate.annotations.GenericGenerator;import org.hibernate.annotations.Parameter;import org.hibernate.criterion.Order;@Entity@Table(name = "customers")public class Customer {	private int id;	private String name;	private Set<Address> addresses;	// @JoinTable注释用于指定连接表和t_customers及t_addresses表的连接字段关系。	@Id	@GenericGenerator(name = "GenericGenerator", strategy = "sequence", parameters = { @Parameter(value = http://www.mamicode.com/"seq_customer", name = "sequence") })>

4.多对多关联图
从上面两个实体类，得到实体关联关系对照图
5.Service
package com.entity.many2many.service;import java.util.HashSet;import java.util.List;import java.util.Set;import javax.annotation.Resource;import org.hibernate.SessionFactory;import org.springframework.stereotype.Service;import org.springframework.transaction.annotation.Transactional;import com.entity.many2many.bean.Address;import com.entity.many2many.bean.Customer;@Service("customerService")@Transactionalpublic class CustomerService {	@Resource	private SessionFactory sessionFactory;	//多对多保存	public void save() {		Customer customer = new Customer();		customer.setName("微软11");		Set<Address> addresses = new HashSet<Address>();		Address address = new Address();		address.setAddressLine("address1");		address.setCountry("中国");		address.setPostCode("12345678");		addresses.add(address);		address = new Address();		address.setAddressLine("address2");		address.setCountry("美国");		address.setPostCode("4321");		addresses.add(address);		customer.setAddresses(addresses);		sessionFactory.getCurrentSession().persist(customer);	}	public void sayHello() {		System.out.println("say Hello");	}	//根据id获取customer信息	public Customer getCustomer(Integer id) {		return (Customer) sessionFactory.getCurrentSession().get(				Customer.class, id);	}	//根据id获取address信息	public Address getAddress(Integer id) {		return (Address) sessionFactory.getCurrentSession().get(Address.class,				id);	}	//根据address id 获取address与customer信息 内连接	public List getCustomsAlls(Integer id) {		return sessionFactory				.getCurrentSession()				.createQuery(						" select DISTINCT o from Address o inner join fetch o.customers where o.id='"+id+"' order by o.id ")				.list();	}	//根据customer id获取customer与address信息	public List getAddressesAlls(Integer id) {		return sessionFactory				.getCurrentSession()				.createQuery(						" select DISTINCT o from Customer o inner join fetch o.addresses where o.id='"+id+"' order by o.id ")				.list();	}	//获取所有的customer与address信息	public List getAlls() {		return sessionFactory				.getCurrentSession()				.createQuery(						" select DISTINCT o from Customer o inner join fetch o.addresses order by o.id ")				.list();	}	//这个方式无法移除关联关系	public void RemoveRelationCustomerNull(Integer id){		Address address=(Address) sessionFactory.getCurrentSession().get(Address.class, id);		address.setCustomers(null);		sessionFactory.getCurrentSession().persist(address);	}	//这个方式无法移除关联关系	public void RemoveRelationAddressNull(Integer id){		Customer customer=(Customer) sessionFactory.getCurrentSession().get(Customer.class, id);		customer.setAddresses(null);		sessionFactory.getCurrentSession().persist(customer);			}	//移除customer	public void RemoveRelationCustomer(Integer id){		Customer customer=(Customer) sessionFactory.getCurrentSession().get(Customer.class, id);		customer.getAddresses().clear();	}	public void RemoveRelationAddress(Integer id){		Address address=(Address) sessionFactory.getCurrentSession().get(Address.class, id);		address.getCustomers().clear();	}	public void deleteCustomer(Integer id){		sessionFactory.getCurrentSession().delete(sessionFactory.getCurrentSession().get(Customer.class, id));	}		public void deleteAddress(Integer id){		sessionFactory.getCurrentSession().delete(sessionFactory.getCurrentSession().get(Address.class, id));	}}

6.Test
package junit.test;import java.util.List;import java.util.Set;import org.junit.BeforeClass;import org.junit.Test;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;import com.entity.many2many.bean.Address;import com.entity.many2many.bean.Customer;import com.entity.many2many.service.CustomerService;public class CustomerServiceTest {	private static CustomerService customerService;	@BeforeClass	public static void setUpBeforeClass() throws Exception {		try {			ApplicationContext applicationContext = new ClassPathXmlApplicationContext(					"beans.xml");			customerService = (CustomerService) applicationContext					.getBean("customerService");		} catch (RuntimeException e) {			e.printStackTrace();		}	}	@Test	public void testSayHello() {		customerService.sayHello();	}	@Test	public void testSave() {		customerService.save();	}	@Test	public void testGetCustomer() {		Customer customer = customerService.getCustomer(1);		System.out.println(customer.getName());	}	@Test	public void testGetAddress() {		Address address = customerService.getAddress(1);		System.out.println(address.getCountry());	}	@Test	public void testGetAll() {		List objects = customerService.getAlls();		for (Customer c : (List<Customer>) objects) {			System.out.println(c.getName());			for (Address a : (Set<Address>) c.getAddresses()) {				System.out.println(a.getCountry());			}		}	}	@Test	public void testGetAddressesAlls() {		List objects = customerService.getAddressesAlls(1);		for (Customer c : (List<Customer>) objects) {			System.out.println(c.getName());			for (Address a : (Set<Address>) c.getAddresses()) {				System.out.println(a.getCountry());			}		}	}	@Test	public void testGetCustomsAlls() {		List objects = customerService.getCustomsAlls(1);		for (Address c : (List<Address>) objects) {			System.out.println(c.getCountry());			for (Customer a : (Set<Customer>) c.getCustomers()) {				System.out.println(a.getName());			}		}	}	// 移除关联关系,同时删除自己	@Test	public void testDeleteCustomes() {		customerService.deleteCustomer(1);	}	// 不能删除本方	// 不能移除关联关系	@Test	public void testDeleteAddress() {		customerService.deleteAddress(22);	}	@Test	public void tesetDeleteAll() {		customerService.deleteCustomer(21);		customerService.deleteAddress(21);	}	//移除关系成功	@Test	public void testRemoveRelationCustomer() {		customerService.RemoveRelationCustomer(3);	}	//移除关系成功	@Test	public void testRemoveRelationAddress() {		customerService.RemoveRelationAddress(2);	}	//无法移除	@Test	public void testRemoveRelationCustomerNull(){		customerService.RemoveRelationCustomerNull(1);	}	//可以移除	@Test	public void testRemoveRelationAddressNull(){		customerService.RemoveRelationAddressNull(2);	}}

 
Hibernate多对多关联关系