Hibernate 菜鸟教程 12 继承 Join策略

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模型对象

父类Employee

public class Employee {
private Long id;
private String name;

子类HourlyEmployee

public class HourlyEmployee extends Employee {
private Double rate;

子类SalariedEmployee

public class SalariedEmployee extends Employee {
private Double salary;

映射文件Employee.hbm.xml

<class name="Employee" table="t_employee">
<id name="id">
<generator class="native" />
</id>
<property name="name" />
<!-- 在配置子类 -->
<joined-subclass name="HourlyEmployee" table="t_HourlyEmployee">
<key column="id"/>
<property name="rate" />
</joined-subclass>
<joined-subclass name="SalariedEmployee" table="t_SalariedEmployee">
<key column="id"/>
<property name="salary" />
</joined-subclass>
</class>

测试对象MainTest

public class MainTest {
Session session = null;
@Before
public void save() {
session = HibernateUtils.INSTANCE.getSession();
session.beginTransaction();

Employee employee = new Employee("jege");

HourlyEmployee hourlyEmployee = new HourlyEmployee();
hourlyEmployee.setName("hourly");
hourlyEmployee.setRate(200D);

SalariedEmployee salariedEmployee = new SalariedEmployee();
salariedEmployee.setName("salaried");
salariedEmployee.setSalary(300D);

session.save(employee);
session.save(hourlyEmployee);
session.save(salariedEmployee);
}

@Test
public void get() {
Employee employee = (Employee) session.get(Employee.class, 1L);
System.out.println(employee.getName());

HourlyEmployee hourlyEmployee = (HourlyEmployee) session.get(HourlyEmployee.class, 2L);
System.out.println(hourlyEmployee.getName());
System.out.println(hourlyEmployee.getRate());

SalariedEmployee salariedEmployee = (SalariedEmployee) session.get(SalariedEmployee.class, 3L);
System.out.println(salariedEmployee.getName());
System.out.println(salariedEmployee.getSalary());
}

@After
public void colse() {
session.getTransaction().commit();
session.close();
}
}

源码地址