Hibernate一对多双向关联映射

/**
 * 部门和员工的关系为一对多，多的一端为关系的维护端，
 * 关系的维护端来负责外键的更新，少的一端无权更新外键字段。
 * @author Liao
 */
public class Department {

	/* 部门Id */
	private Integer id;
	/* 部门名称 */
	private String name;
	/* 部门和员工的关系(一对多) */
	private Set<Employee> employees;

	public Integer getId() {
		return id;
	}

	public void setId(Integer id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public Set<Employee> getEmployees() {
		return employees;
	}

	public void setEmployees(Set<Employee> employees) {
		this.employees = employees;
	}

}

public class Employee {

	/* 员工ID */
	private Integer id;
	/* 员工名称 */
	private String name;
	/* 员工和部门的关系(多对一) */
	private Department department;

	public Integer getId() {
		return id;
	}

	public void setId(Integer 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;
	}

}

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- package表示实体类的包名 -->        
<hibernate-mapping package="com.lixue.bean">
	<!-- class结点的name表示实体的类名，table表示实体映射到数据库中table的名称 -->
	<class name="Department" table="t_department">
		<id name="id" column="did">
			<!-- 自增长 -->
			<generator class="native"/>
		</id>
		<property name="name" column="dname"/>
		
		<!-- 部门和员工的关系(一对多) -->
		<set name="employees" inverse="true">
			<key column="dept_id"/><!-- 表示在多的一端加一个字段 -->
			<one-to-many class="Employee"/>
		</set>
	</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">
<!-- package表示实体类的包名 -->        
<hibernate-mapping package="com.lixue.bean">
	<!-- class结点的name表示实体的类名，table表示实体映射到数据库中table的名称 -->
	<class name="Employee" table="t_employee">
		<id name="id" column="eid">
			<!-- 自增长 -->
			<generator class="native"/>
		</id>
		<property name="name" column="ename"/>
		<!-- 设置Employee和Department的关系column表示和Department.hbm.xml文件的外键映射要一致 -->
		<many-to-one name="department" column="dept_id"/>
	</class>
</hibernate-mapping>

public class One2ManyTest {

	public static void main(String[] args) {
		
		Session session = HibernateUtils.getSession();
		Transaction transaction = session.beginTransaction();
		
		/*创建部门并设置属性*/
		Department department = new Department();
		department.setName("开发部");
		session.save(department);
		
		/*创建员工并设置属性*/
		Employee employee = new Employee();
		employee.setName("习近平");
		employee.setDepartment(department);
		
		session.save(employee);
		
		transaction.commit();
	}
}