hibernate关联关系-多对一

多对一关联关系：

 

模型：员工Employee — 部门Department

 

package Domain;

public class Employee {
	
	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 getDepart() {
		return depart;
	}
	public void setDepart(Department depart) {
		this.depart = depart;
	}
	
	private int id;
	private String name;
	private Department depart;
}

 

 

package Domain;

import java.util.Set;

public class 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 Set<Employee> getEmps() {
		return emps;
	}
	public void setEmps(Set<Employee> emps) {
		this.emps = emps;
	}

	private int id;
	private String name;
	private Set<Employee> emps ;
}

 

 

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC 
	"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
	"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
	
<hibernate-mapping package="Domain">

	<class name="Employee" table="employee">
		<id name="id">
			<generator class="native" />
		</id>
		<property name="name" unique="true"/>
		<many-to-one name="depart" column="depart_id"/>
	</class>
</hibernate-mapping>

 

 

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC 
	"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
	"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
	
<hibernate-mapping package="Domain">

	<class name="Department" table="department">
		<id name="id">
			<generator class="native" />
		</id>
		<property name="name" unique="true"/>
		
		<set name="emps">
			<key column="depart_id"/>
			<one-to-many class="Employee"/>
		</set>
		
	</class>
</hibernate-mapping>

 

package Dao;

import Domain.Employee;

public interface EmployeeDAO {
	public void saveEmployee(Employee emp);
	public Employee findEmployeeByName(String name);
	public Employee findEmployeeById(int id);
	public void updateEmployee(Employee emp);
	public void removeEmployee(Employee emp);
}

 

 

package Dao;

import Domain.Department;


public interface DepartmentDAO {
	public void saveDepartment(Department depart);
	public Department findDepartmentByName(String name);
	public Department findDepartmentById(int id);
	public void updateDepartment(Department depart);
	public void removeDepartment(Department depart);
}

 

 

package Dao.Impl;

import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

import Utils.hibernateUtil;
import Dao.EmployeeDAO;
import Domain.Employee;

public class EmployeeDAOImpl implements EmployeeDAO {

	// 保存员工
	public void saveEmployee(Employee emp) {
		Session s = null;
		Transaction tx = null;
		try{
			s = hibernateUtil.getSession();
			tx = s.beginTransaction();
			s.save(emp);
			tx.commit();
		}catch (HibernateException e) {
			if(tx != null){
				tx.rollback();
			}
			throw e;
		}finally{
			if(s != null){
				s.close();
			}
		}
	}

	// 根据姓名查询员工
	public Employee findEmployeeByName(String name) {
		Session s = null ;
		try{
			s = hibernateUtil.getSession();
			String hql = "from Employee as emp where emp.name=:name";
			Query query = s.createQuery(hql);
			query.setString("name", name);
			Employee emp = (Employee) query.uniqueResult();
			return emp;
		}finally{
			if(s != null){
				s.close();
			}
		}
	}

	// 根据员工id查询员工
	public Employee findEmployeeById(int id) {
		Session s = null ;
		try{
			s = hibernateUtil.getSession();
			Employee emp = (Employee) s.get(Employee.class, id);
			return emp;
		}finally{
			if(s != null)
			{
				s.close();
			}
		}
	}

	// 更新员工信息
	public void updateEmployee(Employee emp) {
		Session s = null;
		Transaction tx = null;
		try{
			s = hibernateUtil.getSession();
			tx = s.beginTransaction();
			s.update(emp);
			tx.commit();
		}catch (HibernateException e) {
			if(tx != null){
				tx.rollback();
			}
			throw e;
		}finally{
			if(s != null){
				s.close();
			}
		}
	}

	// 删除员工
	public void removeEmployee(Employee emp) {
		Session s = null;
		Transaction tx = null;
		try{
			s = hibernateUtil.getSession();
			tx = s.beginTransaction();
			s.delete(emp);
			tx.commit();
		}catch (HibernateException e) {
			if(tx != null){
				tx.rollback();
			}
			throw e;
		}finally{
			if(s != null){
				s.close();
			}
		}
	}
}

 

 

package Dao.Impl;


import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;


import Dao.DepartmentDAO;
import Domain.Department;
import Utils.hibernateUtil;


public class DepartmentDAOImpl implements DepartmentDAO {

	// 保存部门
	public void saveDepartment(Department depart) {
		Session s = null;
		Transaction tx = null;
		try{
			s = hibernateUtil.getSession();
			tx = s.beginTransaction();
			s.save(depart);
			tx.commit();
		}catch (HibernateException e) {
			if(tx != null){
				tx.rollback();
			}
			throw e;
		}finally{
			if(s != null){
				s.close();
			}
		}
	}

	// 根据name查找部门
	public Department findDepartmentByName(String name) {
		Session s = null ;
		try{
			s = hibernateUtil.getSession();
			String hql = "from Department as depart where depart.name=:name";
			Query query = s.createQuery(hql);
			query.setString("name", name);
			Department depart = (Department) query.uniqueResult();
			return depart;
		}finally{
			if(s != null){
				s.close();
			}
		}
	}

	// 根据id查找部门
	public Department findDepartmentById(int id) {
		Session s = null ;
		try{
			s = hibernateUtil.getSession();
			Department depart = (Department) s.get(Department.class, id);
			return depart;
		}finally{
			if(s != null)
			{
				s.close();
			}
		}
	}

	// 更新部门
	public void updateDepartment(Department depart) {
		Session s = null;
		Transaction tx = null;
		try{
			s = hibernateUtil.getSession();
			tx = s.beginTransaction();
			s.update(depart);
			tx.commit();
		}catch (HibernateException e) {
			if(tx != null){
				tx.rollback();
			}
			throw e;
		}finally{
			if(s != null){
				s.close();
			}
		}
	}
	
	// 删除部门
	public void removeDepartment(Department depart) {
		Session s = null;
		Transaction tx = null;
		try{
			s = hibernateUtil.getSession();
			tx = s.beginTransaction();
			s.delete(depart);
			tx.commit();
		}catch (HibernateException e) {
			if(tx != null){
				tx.rollback();
			}
			throw e;
		}finally{
			if(s != null){
				s.close();
			}
		}
	}
}

 

 

package Dao.Test;

import org.hibernate.Session;
import org.hibernate.Transaction;

import Utils.hibernateUtil;

import Domain.Department;
import Domain.Employee;

public class Many2OneTest {
	public static void main(String[] args) {
		add();
	}
	
	public static Department add(){
		Session s = null ;
		Transaction tx = null;
		try{
			Department depart = new Department();
			depart.setName("xuan chuan bu");
			
			Employee emp = new Employee();
			emp.setDepart(depart);// 对象模型，建立两个对象间的关联关系
			emp.setName("zhang zuoqiang");
			
			s = hibernateUtil.getSession();
			tx = s.beginTransaction();
			
			s.save(depart);
			s.save(emp);
			
			tx.commit();
			
			return depart;
		}finally{
			if(s != null){
				s.close();
			}
		}
	}
}

 

评论

1 楼 csdn_zuoqiang 2010-08-03  

一对多测试：

package Dao.Test;

import org.hibernate.Session;
import org.hibernate.Transaction;

import Utils.hibernateUtil;
import Domain.Department;
import Domain.Employee;

public class One2ManyTest {
public static void main(String[] args) {
Department depart = add();
queryDepart(depart.getId());
}

static Department queryDepart(int departId) {
Session s = null;
try {
s = hibernateUtil.getSession();
Department depart = (Department) s.get(Department.class, departId);
System.out.println("emp  size: " + depart.getEmps().size());
return depart;
} finally {
if (s != null)
s.close();
}
}

static Department add() {
Session s = null;
Transaction tx = null;
try {
Department depart = new Department();
depart.setName("+Manager+");

Employee emp1 = new Employee();
emp1.setDepart(depart);
// 对象模型：建立两个对象的关联
emp1.setName("emp name1");

Employee emp2 = new Employee();
emp2.setDepart(depart);
// 对象模型：建立两个对象的关联
emp2.setName("emp name2");

/*Set<Employee> emps = new HashSet<Employee>();
emps.add(emp1);
emps.add(emp2);
depart.setEmps(emps);*/

s = hibernateUtil.getSession();
tx = s.beginTransaction();

s.save(depart);
s.save(emp1);
s.save(emp2);
System.out.println("-----------------");
tx.commit();

return depart;
} finally {
if (s != null)
s.close();
}
}
}