Hibernate多对一双向关联(xml配置)

转载地址：http://www.blogjava.net/sxyx2008/archive/2010/10/18/335461.html

Hibernate多对一双向关联(xml配置)

Department.java

package com.many2one.bean;

import java.util.Set;

public class Department {
    
    private int id;
    private String name;
    private Set<Employee> sets;
    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 Set<Employee> getSets() {
        return sets;
    }
    public void setSets(Set<Employee> sets) {
        this.sets = sets;
    }
    
}

Employee.java

package com.many2one.bean;


public class Employee {
    
    private int id;
    private String name;
    private Department department;
    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 Department getDepartment() {
        return department;
    }
    public void setDepartment(Department department) {
        this.department = department;
    }
    
    
}

映射文件
Department.hbm.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC 
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
    <hibernate-mapping package="com.many2one.bean">
        <class name="Department" table="department" catalog="Hibernate_Many2One">
            <id name="id" column="id">
                <generator class="native"/>
            </id>
            <property name="name" column="name"/>
            
        </class>
    </hibernate-mapping>

Employee.hbm.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC 
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
    <hibernate-mapping package="com.many2one.bean">
        <class name="Employee" table="employee" catalog="Hibernate_Many2One">
            <id name="id" column="id">
                <generator class="native"/>
            </id>
            <property name="name" column="name"/>
            <many-to-one name="department" column="deptid" cascade="all" />
        </class>
    </hibernate-mapping>

导出的sql

create table Hibernate_Many2One.department (
        id integer not null auto_increment,
        name varchar(255),
        primary key (id)
    )

    create table Hibernate_Many2One.employee (
        id integer not null auto_increment,
        name varchar(255),
        deptid integer,
        primary key (id)
    )

    alter table Hibernate_Many2One.employee 
        add index FK4722E6AE3829E242 (deptid), 
        add constraint FK4722E6AE3829E242 
        foreign key (deptid) 
        references Hibernate_Many2One.department (id)

测试代码

@Test
    public void insert(){
        Session session=HibernateSessionFactory.getSession();
        Transaction transaction=session.beginTransaction();
        try {
            transaction.begin();
            Department department=new Department();
            department.setName("软件测试部");
            Employee employee=new Employee();
            employee.setName("张三");
            employee.setDepartment(department);
            session.save(employee);
            transaction.commit();
        } catch (HibernateException e) {
            e.printStackTrace();
        }
    }
    
    
    @Test
    public void select(){
        Session session=HibernateSessionFactory.getSession();
        try {
            Employee employee=(Employee) session.get(Employee.class, 1);
            System.out.println(employee.getName());
            System.out.println(employee.getDepartment().getName());
        } catch (HibernateException e) {
            e.printStackTrace();
        }
    }