首页 > 解决方案 > 在 Spring 应用程序中运行测试时的 NPE(JUnit 5、Mockito 3、Spring JPA 存储库)

问题描述

我正在使用 Mockito 3.1.0 和 Junit 5.5.2 运行一个基本的 Spring 应用程序。我有一个包含两个 Spring Data JPA 存储库的服务调用。这些被传递到 DI 的构造函数中(以及另外两个无关紧要的 - 我将它们包括在内,以防它们也可能导致错误。)当应用程序运行时,我发现服务没有问题。

当我运行测试时,我得到了myService. 单步执行堆栈跟踪,并没有真正向我展示与错误相关的任何内容。我也尝试过(在这篇文章之后:https ://www.baeldung.com/mockito-junit-5-extension )更新我的测试类看起来像这样:

@ExtendWith(MockitoExtension.class)
@RunWith(JUnitPlatform.class) // This dependency doesn't seem to exist
public class MyServiceTest {
    // ...

    @BeforeEach 
    // not the JUnit4 @Before annotation.
    // Interestingly, this gives me NPEs for the repositories, not the service.
    public void setup(){
        // ...
    }
}

无济于事。我怀疑正在发生的事情是我的设置没有正确连接——无论是作为依赖项还是 DI 的语法。

我该如何调试?我错过了什么?提前致谢!

服务:

import org.springframework.stereotype.Service;

@Service
public class MyService {
    private final Repository1 repository1;
    private final Repository2 repository2;
    private final Repository3 repository3;
    private final Repository4 repository4;

  public MyService(Repository1 repository1,
      Repository2 repository2,
      Repository3 repository3,
      Repository4 repository4) {
    this.repository1 = repository1;
    this.repository2 = repository2;
    this.repository3 = repository3;
    this.repository4 = repository4;
  }

    public Boolean computeValue(String someInput) {
        // does computations with repository1, repository2.
    }
}

测试:

import static org.mockito.Mockito.when;
import static org.junit.jupiter.api.Assertions.assertTrue;
import org.junit.jupiter.api.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.junit.MockitoJUnitRunner;

@RunWith(MockitoJUnitRunner.class)
public class MyServiceTest {

    @Mock
    private Repository1 repository1;

    @Mock
    private Repository2 repository2;

    @Mock
    private Repository3 repository3;

    @Mock
    private Repository4 repository4;

    @InjectMocks
    private MyService myService;

    @Before
    public void setup {
        when(repository1.findAll()).thenReturn(new ArrayList<>());
        when(repository1.findAllByInput(anyString())).thenReturn(new ArrayList<>());
        // Yes; I'm aware that this could also be a call to
        // MockitoAnnotations.initMocks(this). I've tried it:
        // it doesn't work. Also, I've intentionally not taken this
        // approach due to reasons:
        //   - https://stackoverflow.com/questions/10806345/runwithmockitojunitrunner-class-vs-mockitoannotations-initmocksthis
    }

    @Test
  void callMyService() {
        assertTrue(myService.computeValue("123"));
    }
}

样本库:

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

// This is just an example, but this pattern is repeated against all
// repositories in the project.
@Repository
public interface Repository1 extends JpaRepository<Repository1, String> {
}

编辑:

标签: javaspringspring-bootjunitmockito

解决方案


对于将来遇到此问题的任何其他人,我们能够通过更改其中一个导入来解决此问题:

import org.junit.jupiter.api.Test;

import org.junit.Test;

编辑:


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