java - hibernate 和 JUnit

Question

我是 JUnit 测试的新手。每当我尝试测试具有 hibernate 查询结果空指针错误的方法时，例如

java.lang.NullPointerException
    at com.fetchinglife.application.modules.employee.view.EmployeeList.empList(EmployeeList.java:209)

我的测试课是:

public class EmployeeListTest extends TestCase {

    private EmployeeList employeeList = new EmployeeList();
    public static HibernateTemplate hibernateTemplate;

    @BeforeClass
    public void setUpBeforeClass() throws Exception {

              SessionFactory  sessionFactory = this.hibernateTemplate.getSessionFactory();
         Session session = sessionFactory.openSession();
          System.out.println("in before");
    }

        @Test
    public void testGetEmployees() throws HibernateException, SQLException {        

        List<Employee> employees = employeeList.getEmpList();       
        assertNotNull(employees);
    }

但是 testGetEmployees() 的空指针错误
而我在 EmployeeList 中的方法是 :

public List<Employee> empList() {       

        try
        {
            @SuppressWarnings("unchecked")
            List <Employee> result =  hibernateTemplate.find("from Employee"); 
            return result;
        }
        finally { 
        }
    }

我还需要添加什么？我使用的是 JUnit 4。

我的 EmployeeList.java 在这里。

@Component("employeeList")
@SessionScoped
@Repository
public class EmployeeList implements Serializable {
    private static final long serialVersionUID = -2417394435764260084L;

    public static HibernateTemplate hibernateTemplate;

    @Autowired
    public void setSessionFactory(SessionFactory sessionFactory)
    {
        this.hibernateTemplate = new HibernateTemplate(sessionFactory);
    }

    private Employee employee = new Employee();

    public List<Employee> getEmployees() throws HibernateException, SQLException {
        List<Employee> employees = new ArrayList<Employee>();
        System.out.println("in getEmployeess");
        employees.addAll(empList());    
        return employees;

    }

    public List<Employee> empList() {       

        System.out.println(" find all employees: ");    
        try
        {

            @SuppressWarnings("unchecked")
            List <Employee> result =  hibernateTemplate.find("from Employee"); 
            return result;
        }
        finally { 
        }

    }

    public Employee getEmployee() {
        return employee;
    }

    public void setEmployee(Employee employee) {
        this.employee = employee;
    }
}

我试图检索 hibernateTemplate 但仍然错误。我不知道我哪里错了。

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "/spring/servlet-config.xml")
public class EmployeeListTest extends TestCase {
    private static HibernateTemplate hibernateTemplate;

    @Autowired
    private EmployeeList employeeList;

    @BeforeClass
    public static void setUpBeforeClass() throws Exception {

        SessionFactory  sessionFactory = hibernateTemplate.getSessionFactory();
        Session session = sessionFactory.openSession();     
    }

    @Test
    public void testGetEmployees() throws HibernateException, SQLException {
        List<Employee> employees = employeeList.getEmployees();     
        assertNotNull(employees);
    }
}

Answer 1

空指针异常是因为 hibernateTemplate 为空(检查 EmployeeList.java:209 行)。发生这种情况是因为您在测试类中创建了一个新的 EmployeeList 对象 - 它应该从 spring 上下文中检索。

您需要配置您的测试以创建一个 spring 应用程序上下文，然后将 EmployeeList 作为依赖项注入(inject)

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("<put your spring config file here>")
public class EmployeeListTest extends TestCase {
    @Autowired
    private EmployeeList employeeList