使用 Mockito 进行 Service 层单元测试：详细教程

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-test</artifactId>
    <scope>test</scope>
</dependency>
<dependency>
    <groupId>org.mockito</groupId>
    <artifactId>mockito-core</artifactId>
    <scope>test</scope>
</dependency>

// ScoreDAO.java
public interface ScoreDAO {
    int insert(ScoreModel score);
}

// SubjectService.java
public interface SubjectService {
    SubjectModel getNameSubject(RequestModel request, String nameStudent);
}

// ExamServiceImpl.java
@Service
public class ExamServiceImpl implements ExamService {

    @Autowired
    private SubjectService subjectService;

    @Autowired
    private ScoreDAO scoreDAO;

    @Autowired
    private TeacherDAO teacherDAO;

    @Autowired
    private StudentDAO studentDAO;


    @Override
    public ResponseModel insertScore(RequestModel request) throws IOException {
        List<TeacherModel> teacher = teacherDAO.getNameList(request);
        List<StudentModel> student = studentDAO.findStudentList(teacher.get(0).getName(), request.getStudentScore);

        String nameStudent = student.get(0).getFirstName() + student.get(0).getLastName();
        SubjectModel subject = subjectService.getNameSubject(request, nameStudent);

        ScoreModel score = new ScoreModel();
        score.setStudentName(request.getStudentName);
        score.setScore(request.getStudentScore);
        score.setSubject(subject.getName);

        int result = scoreDAO.insert(score);

        return new ResponseModel(result); // Changed to return ResponseModel
    }
}

import org.junit.jupiter.api.Test;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.Mockito;
import org.springframework.boot.test.context.SpringBootTest;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.ArgumentMatchers.anyString;
import static org.mockito.Mockito.when;

@SpringBootTest
public class ExamServiceImplTest {

    @Mock
    private ScoreDAO scoreDAO;

    @Mock
    private SubjectService subjectService;

    @Mock
    private TeacherDAO teacherDAO;

    @Mock
    private StudentDAO studentDAO;

    @InjectMocks
    private ExamServiceImpl examService;

    @Test
    void insertScoreTest() throws IOException {
        // 1. 定义 Mock 对象的行为
        SubjectModel resFromSubject = new SubjectModel();
        resFromSubject.setName("Math");

        TeacherModel resTeacher = new TeacherModel();
        resTeacher.setName("test Teacher");
        List<TeacherModel> teacherList = new ArrayList<>();
        teacherList.add(resTeacher);

        StudentModel studentData = new StudentModel();
        studentData.setFirstName("firstname");
        studentData.setLastName("lastname");
        List<StudentModel> studentList = new ArrayList<>();
        studentList.add(studentData);

        when(teacherDAO.getNameList(any(RequestModel.class))).thenReturn(teacherList);
        when(studentDAO.findStudentList(anyString(), anyString())).thenReturn(studentList);
        when(subjectService.getNameSubject(any(RequestModel.class), anyString())).thenReturn(resFromSubject);
        when(scoreDAO.insert(any(ScoreModel.class))).thenReturn(1);

        // 2. 执行被测方法
        ResponseModel resultTest = examService.insertScore(new RequestModel());

        // 3. 验证结果
        assertEquals(1, resultTest.getResult());
    }
}