Junit4 + Mockito unit testing practical case

Practical
code examples:

1. Introduce dependencies

            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <version>2.1.0.RELEASE</version>
            </dependency>
引入spring-boot-starter-test依赖就好，因为此版本的框架中默认集成了Junit4和Mockito。

2. Introduce the plug-in TestMe

​​​​​​​​​​​Note
: This plug-in cannot be searched for versions before idea2021.3.3.

3. Writing unit test code

Use TestMe to automatically generate unit test code:

public class UserServiceImplTest {
    
    
    //创建模拟对象
    @Mock
    UserManager userManager;
    //注入mock对象
    @InjectMocks
    UserServiceImpl userServiceImpl;

    @Before
    public void setUp() {
    
    
        //使@Mock和@InjectMocks对象生效
        MockitoAnnotations.initMocks(this);
    }

    @Test
    public void testGetUserByUid() throws Exception {
    
    
        User user = new User();
        user.setUid(2055755111L);
        user.setCountryId(1);
        //设置模拟对象的行为
        when(userManager.getUserByUid(111L)).thenReturn(user);
        //执行代码
        User user = userServiceImpl.getUserByUid(111L);
        //断言结果是否符合预期
        Assert.assertNotNull(user);
    }
}
public class UserServiceImpl{
    
    
    @Autowired
    UserManager userManager;
    public User getUserByUid(Long uid) {
    
    
      //Some logics
      User user = userManager.getUserByUid(111L);
      //Another logics
    }
}

4. Automate unit testing

Unit tests that are not executed automatically are meaningless. There are so many unit tests in the project, are they one by one?
Introduce the maven-surefire-plugin plug-in for automated execution of single tests.

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
                <version>2.22.1</version>
                <configuration>
                    <includes>
                        <include>com.user.service.UserServiceImpl</include>                   
                    </includes>
                </configuration>
            </plugin>

Include represents the single test class that needs to be executed. A large number of classes can be defined, such as: **/*Tests.java (all Java files ending with "Test").
Execute maven command:

mvn clean test   先清除旧的编译项目，在运行test内容。

Under surefire-reports under the target, you can see the single test report just run.

5. Generate test rate coverage report

Order:

mvn cobertura:cobertura

You can see the coverage report in index.html under site.

It probably looks like this:

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