顾客与顾客的多对多映射，以及顾客和订单，商户与订单的一对多映射
Posted acefeng
tags:
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customer.java
package Entity;
import java.util.HashSet;
import java.util.Set;
//import org.hibernate.mapping.Set;
public class Customer {//每个顾客可以对应多个商家，每个商家可以对应多个顾客
private int cid;
private String name;
private Set<Merchant> merchant=new HashSet<Merchant>();
public int getCid() {
return cid;
}
public void setCid(int cid) {
this.cid = cid;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Set<Merchant> getMerchant() {
return merchant;
}
public void setMerchant(Set<Merchant> merchant) {
this.merchant = merchant;
}
public Customer(int cid, String name, Set<Merchant> merchant) {
super();
this.cid = cid;
this.name = name;
this.merchant = merchant;
}
public Customer(){}
@Override
public String toString() {
return "cid=" + cid + ", name=" + name ;
}
}
Merchant.java
package Entity;
import java.util.HashSet;
import java.util.Set;
public class Merchant {//多个商户可对应多个顾客
private int mid;
private String name;
private Set<Customer> customer=new HashSet<Customer>();
public int getMid() {
return mid;
}
public void setMid(int mid) {
this.mid = mid;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Set<Customer> getCustomer() {
return customer;
}
public void setCustomer(Set<Customer> customer) {
this.customer = customer;
}
public Merchant(int mid, String name, Set<Customer> customer) {
super();
this.mid = mid;
this.name = name;
this.customer = customer;
}
public Merchant(){}
@Override
public String toString() {
return "mid=" + mid + ", name=" + name +"]";
}
}
order.java
package Entity;
import java.util.Date;
public class Order {//与顾客是多对一的关系
private int id;
private String name;
private Customer customer;
private Merchant merchant;
private String message;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Customer getCustomer() {
return customer;
}
public void setCustomer(Customer customer) {
this.customer = customer;
}
public Merchant getMerchant() {
return merchant;
}
public void setMerchant(Merchant merchant) {
this.merchant = merchant;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
public Order(int id, String name, Customer customer, Merchant merchant, String message) {
super();
this.id = id;
this.name = name;
this.customer = customer;
this.merchant = merchant;
this.message = message;
}
public Order(){}
@Override
public String toString() {
return "id=" + id + ", name=" + name+ ", message="
+ message ;
}
}
切记：toString方法中不要返回customer和merchant，上面的也是
映射文件：
customer：
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "hibernate-mapping-3.0.dtd" >
<hibernate-mapping>
<class name="Entity.Customer" table="t_customer">
<id name="cid" column="cid" type="int">
<generator class="increment"/>
</id>
<property name="name" column="name" type="java.lang.String" />
<set name="merchant" table="c_m" cascade="all">
<key column="c_id"></key>
<many-to-many class="Entity.Merchant" column="m_id"></many-to-many>
</set>
</class>
</hibernate-mapping>
merchant的映射
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "hibernate-mapping-3.0.dtd" >
<hibernate-mapping>
<class name="Entity.Merchant" table="t_merchant">
<id name="mid" column="mid" type="int">
<generator class="increment"/>
</id>
<property name="name" column="name" type="java.lang.String" />
<set name="customer" table="c_m" inverse="true"><!-- 顾客方决定 -->
<key column="m_id"></key>
<many-to-many class="Entity.Customer" column="c_id"></many-to-many>
</set>
</class>
</hibernate-mapping>
order的映射文件
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "hibernate-mapping-3.0.dtd" >
<hibernate-mapping>
<class name="Entity.Order" table="t_order">
<id name="id" column="id" type="int">
<generator class="increment"/>
</id>
<property name="name" column="name" type="java.lang.String" />
<property name="message" column="message" type="java.lang.String" />
<many-to-one name="customer" column="cid" class="Entity.Customer" cascade="all"></many-to-one>
<many-to-one name="merchant" column="mid" class="Entity.Merchant" cascade="all"></many-to-one>
</class>
</hibernate-mapping>
config配置文件
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd
">
<hibernate-configuration>
<session-factory>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/test</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password"></property>
<!-- <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property> -->
<property name="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>
<property name="show_sql">true</property>
<!-- <property name="hibernate.hbm2ddl.auto">create</property> -->
<property name = "hibernate.current_session_context_class">thread</property>
<!-- <mapping resource="text/user.hbm.xml"/> -->
<mapping resource="Entity/customer.hbm.xml"/>
<mapping resource="Entity/merchant.hbm.xml"/>
<mapping resource="Entity/order.hbm.xml"/>
</session-factory>
</hibernate-configuration>
自己测试的
package Usertest;
import java.util.List;
import java.util.Scanner;
import java.util.Set;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.query.Query;
import Entity.Customer;
import Entity.Merchant;
import Entity.Order;
import org.junit.Test;
//顾客方决定的
public class C_M_tset {
@Test
public void save(){
SessionFactory sf = HibernateUtil.getSessionFactory();
Session session = sf.getCurrentSession();
Transaction ts = session.beginTransaction();
try {
Customer customer1=new Customer();
Customer customer2=new Customer();
Merchant merchant1=new Merchant();
Merchant merchant2=new Merchant();
Order order1=new Order();
customer1.setName("customer3");
merchant1.setName("merchant3");
customer2.setName("customer4");
merchant2.setName("merchant4");
order1.setCustomer(customer1);
order1.setName("order2");
order1.setMessage("It is for customer3");
order1.setMerchant(merchant1);
customer1.getMerchant().add(merchant1);
customer1.getMerchant().add(merchant2);
customer2.getMerchant().add(merchant1);
session.save(customer1);
session.save(customer2);
session.save(order1);
System.out.println(order1);
ts.commit();
} catch (HibernateException e) {
// TODO Auto-generated catch block
if(ts != null)
{
ts.rollback();
}
e.printStackTrace();
}
}
@Test
public void save2(){
SessionFactory sf = HibernateUtil.getSessionFactory();
Session session = sf.getCurrentSession();
Transaction ts = session.beginTransaction();
try {
Customer customer1=new Customer();
customer1.setName("Amy");
Merchant merchant1=new Merchant();
merchant1.setName("Tom");
customer1.getMerchant().add(merchant1);
session.save(merchant1);
session.save(customer1);
Order order1=new Order();
order1.setCustomer(customer1);
order1.setMerchant(merchant1);
order1.setName("oh");
order1.setMessage("about Tom AND Amy");
session.save(order1);
ts.commit();
} catch (HibernateException e) {
// TODO Auto-generated catch block
if(ts != null)
{
ts.rollback();
}
e.printStackTrace();
}
}
@Test
public void save3(){
SessionFactory sf = HibernateUtil.getSessionFactory();
Session session = sf.getCurrentSession();
Transaction ts = session.beginTransaction();
try {
Customer customer1=new Customer();
Customer customer2=new Customer();
Merchant merchant1=new Merchant();
Merchant merchant2=new Merchant();
Order order1=new Order();
customer1.setName("customer3");
merchant1.setName("merchant3");
customer2.setName("customer4");
merchant2.setName("merchant4");
order1.setCustomer(customer1);
order1.setName("order2");
order1.setMessage("It is for customer3");
order1.setMerchant(merchant1);
//顾客1同时购买商家2和商家1的东西,顾客3同时购买商户3和商户4的东西
customer1.getMerchant().add(merchant1);
customer1.getMerchant().add(merchant2);
// //顾客2只购买了商家1//顾客4购买商户3
customer2.getMerchant().add(merchant1);
session.save(customer1);
session.save(customer2);
session.save(order1);
System.out.println(order1);
ts.commit();
} catch (HibernateException e) {
// TODO Auto-generated catch block
if(ts != null)
{
ts.rollback();
}
e.printStackTrace();
}
}
@Test
public void query(){
SessionFactory sf = HibernateUtil.getSessionFactory();
Session session = sf.getCurrentSession();
Transaction ts = session.beginTransaction();
try {
Order order=session.get(Order.class, 1);
System.out.println(order);
System.out.println("顾客"+order.getCustomer().getName()+
"买的商户"+order.getMerchant().getName()+"的商品，订单号为"+order.getId()+
"订单信息为"+order.getMessage());
Customer customer=session.get(Customer.class, 1);
System.out.println("顾客"+customer.getName());
System.out.println("买了商家"+customer.getMerchant());
ts.commit();
} catch (HibernateException e) {
// TODO Auto-generated catch block
if(ts != null)
{
ts.rollback();
}
e.printStackTrace();
}
}
@Test
public void update(){
SessionFactory sf = HibernateUtil.getSessionFactory();
Session session = sf.getCurrentSession();
Transaction ts = session.beginTransaction();
try {
Customer customer=session.get(Customer.class, 6);
customer.setName("baxueyu");
ts.commit();
} catch (HibernateException e) {
// TODO Auto-generated catch block
if(ts != null)
{
ts.rollback();
}
e.printStackTrace();
}
}
@Test
public void queryCustomerbymerchantId(){
SessionFactory sf = HibernateUtil.getSessionFactory();
Session session = sf.getCurrentSession();
Transaction ts = session.beginTransaction();
try {
Query query=session.createQuery("select c from Customer c join c.merchant m where m.mid=1");
List customer = query.list();
for(int i=0;i<customer.size();i++)
{
Customer customers =(Customer)customer.get(i);
System.out.println(i+"--"+customers);
}
ts.commit();
} catch (HibernateException e) {
// TODO Auto-generated catch block
if(ts != null)
{
ts.rollback();
}
e.printStackTrace();
}
}
@Test
public void queryCustomerbyOrderId(){
SessionFactory sf = HibernateUtil.getSessionFactory();
Session session = sf.getCurrentSession();
Transaction ts = session.beginTransaction();
// int n;
// Scanner sc=new Scanner(System.in);
// n=sc.nextInt();
try {
Query query=session.createQuery("select customer from Order o where o.id=1" );
System.out.println(query);
List customer = query.list();
for(int i=0;i<customer.size();i++)
{
Customer customers =(Customer)customer.get(i);
System.out.println(i+"--"+customers);
}
ts.commit();
} catch (HibernateException e) {
// TODO Auto-generated catch block
if(ts != null)
{
ts.rollback();
}
e.printStackTrace();
}
}
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