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import java.util.HashSet;
import java.util.Set;
import org.hibernate.Session;
import org.hibernate.Transaction;
import cn.itcast.hibernate.HibernateUtil;
import cn.itcast.hibernate.domain.Department;
import cn.itcast.hibernate.domain.User1;
public class ManyToOneTest {
public static void main(String[] args) {
Session session = null;
Transaction tx = null;
/* try {
session = HibernateUtil.getSession();
tx = session.beginTransaction();
Department department = new Department("研发部");
User1 user1 = new User1();
user1.setName("小新");
user1.setDepartment(department);
session.save(department);
session.save(user1);
tx.commit();
} catch (HibernateException e) {
if (tx!=null) {
tx.rollback();
}
e.printStackTrace();
}finally{
if (session!=null) {
session.close();
}
}*/
/* //获得
try {
session = HibernateUtil.getSession();
User1 user1 = (User1)session.get(User1.class, 5);
System.out.println(user1.getName());
Department department = user1.getDepartment();
System.out.println(department.getName());
session.close();
} catch (Exception e) {
e.printStackTrace();
}*/
try {
session = HibernateUtil.getSession();
tx = session.beginTransaction();
//新建几个用户
User1 usera = new User1();
usera.setName("一号");
User1 userb = new User1();
userb.setName("二号");
Set<User1> users = new HashSet<User1>();
users.add(usera);
users.add(userb);
//新建部门
Department department = new Department("业务部");
department.setUsers(users);
session.save(department);
session.save(usera);
session.save(userb);
tx.commit();
} catch (Exception e) {
e.printStackTrace();
}
}
}
<?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="cn.itcast.hibernate.domain">
<class name="User1" table="user1">
<id name="id" unsaved-value="-1">
<generator class="native" />
</id>
<property name="name"/>
<many-to-one name="department" column="deptid"/>
</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="cn.itcast.hibernate.domain">
<class name="Department" table="Department">
<id name="id" unsaved-value="-1">
<generator class="native" />
</id>
<property name="name"/>
<set name="users">
<key column="deptid"/>
<one-to-many class="User1"/>
</set>
</class>
</hibernate-mapping>
a实体 多对一 b实体
a实体中有b实体的引用
public class User1 {
private int id;
private String name;
private Department department;
public Department getDepartment() {
return department;
}
public void setDepartment(Department department) {
this.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 class Department {
private Integer id;
private String name;
private Set<User1> users;
public Set<User1> getUsers() {
return users;
}
public void setUsers(Set<User1> users) {
this.users = users;
}
public Department(){}
public Department(String name) {
this.name = name;
}
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;
}
}