java - Spring Data JPA findById()引发ClassCastException

我有一个使用Spring Data JPA的findById()方法的方法。但是，此方法在我调用findById（）的getSupportedKey（）方法的第1行上返回ClassCastException：

MySupportedKey cannot be cast to java.util.Optional

private MySupportedKey getSupportedKey(String tenant, String key) {
        Optional<MySupportedKey> mySupportedKeyOptional = mySupportedKeyRepository.findById(new MySupportedKeyId(tenant, key));
        MySupportedKey mySupportedKey= null;
        if(mySupportedKeyOptional !=null) {
             mySupportedKey= mySupportedKeyOptional.orElse(null);
        }
        return mySupportedKey;
    }

我已经很长一段时间不停地跳动了，但什么也没得到。请帮助我解决此问题。我正在使用spring-data-jpa：2.0.8.RELEASE。

添加存储库源代码：

public interface MySupportedKeyRepository extends JpaRepository<MySupportedKey, MySupportedKeyId> {

List<MySupportedKey> findByIdTenant(@NotNull String tenant);
}

添加错误的完整堆栈跟踪：

java.lang.ClassCastException: com.test.service.user.entity.MySupportedKey cannot be cast to java.util.Optional
at com.test.service.user.repository.MySupportedKeyRepository$MockitoMock$1304362870.findById(Unknown Source)
at com.test.service.user.repository.MySupportedKeyRepository$MockitoMock$1304362870.findById(Unknown Source)
at com.test.service.user.userpreferences.PreferencesServiceImpl.getSupportedKey(PreferencesServiceImpl.java:217)
at com.test.service.user.userpreferences.PreferencesServiceImpl.updateUserPreferences(PreferencesServiceImpl.java:167)
at com.test.service.user.userpreferences.PreferencesServiceImpl.lambda$2(PreferencesServiceImpl.java:92)
at java.util.ArrayList.forEach(Unknown Source)
at com.test.service.user.userpreferences.PreferencesServiceImpl.updateUserPreferences(PreferencesServiceImpl.java:92)
at com.test.service.user.preferences.PreferencesServiceImplTest.updateUserPreferences(PreferencesServiceImplTest.java:300)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
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.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.mockito.internal.junit.JUnitRule$1.evaluateSafely(JUnitRule.java:52)
at org.mockito.internal.junit.JUnitRule$1.evaluate(JUnitRule.java:43)
at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
at org.springframework.test.context.junit4.statements.RunPrepareTestInstanceCallbacks.evaluate(RunPrepareTestInstanceCallbacks.java:64)
at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
at org.springframework.test.context.junit4.statements.SpringFailOnTimeout.evaluate(SpringFailOnTimeout.java:87)
at org.springframework.test.context.junit4.statements.ProfileValueChecker.evaluate(ProfileValueChecker.java:103)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
at org.springframework.test.context.junit4.statements.ProfileValueChecker.evaluate(ProfileValueChecker.java:103)
at org.springframework.test.context.junit4.rules.SpringClassRule$TestContextManagerCacheEvictor.evaluate(SpringClassRule.java:230)
at org.junit.rules.RunRules.evaluate(RunRules.java:20)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:538)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:760)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:460)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:206)

最佳答案

您为存储库设置了一个Mockito模拟，并可能告诉它在调用MySupportedKey时返回一个findById实例。
但是由于findById应该返回Optional，因此您现在获得了异常。

您可以在堆栈跟踪的前两行看到这来自Mockito。

java.lang.ClassCastException: com.test.service.user.entity.MySupportedKey cannot be cast to java.util.Optional
at com.test.service.user.repository.MySupportedKeyRepository$MockitoMock$1304362870.findById(Unknown Source)

关于java - Spring Data JPA findById()引发ClassCastException，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/51035739/