BeforeClass中的NullPointerException（spring boot）

Question

我想在所有测试之前在我的数据库中插入一次。这就是我在setUp（）方法中尝试做的事情。但是得到了nullpointer。Spring boot版本是1.5.1.发行版。有什么想法吗？这是来自我的测试类：

@Autowired
    private static UserRepository userRepository;

    @BeforeClass
    public static void setUp() {
        User user = User.
                .builder()
                .id(10)
                .name("John")
                .build();

        userRepository.deleteAll(); //NullPointerException at this step
        userRepository.save(user);
    }

@Entity
@Table(schema="test", name = "TBL_USERS")
@AllArgsConstructor
@Builder
@Data public class User implements Persistable<String>{

    @Id
    @Column(name = "ID", columnDefinition = "decimal")
    private String id;

    @Column(name = "NAME", columnDefinition = "char", nullable = false)
    private String name;

    ...
    }

public interface UserRepository extends JpaRepository<User, String> {}

java.lang.NullPointerException
    at com.company.myapp.get.GetUserTest.setUp(GetUserTest.java:58)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:24)
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:51)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:237)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)

Answer 1

简短回答：您不能注入静态Userrepository(@autowired)

请阅读这里的原因，我们不能注入静态字段