自动连接，给出 NullPointerException

问：

我有一个Exception类：

@Component  
public class PushDataException extends RuntimeException {

@Autowired
private PushDataTraceLogService pushDataTraceLogService;

不知何故，在尝试使用 时，我得到了空指针，而类如下所示：pushDataTraceLogServicePushDataTraceLogService

public interface PushDataTraceLogService { 
    void save(PushDataTraceLog pushDataTraceLog);

这在课堂上实现：PushDataTraceLogServiceImpl

@Service
public class PushDataTraceLogServiceImpl implements PushDataTraceLogService {

    @Autowired
    private PushDataTraceLogRepository pushDataTraceLogRepository;

    @Override
    public void save(PushDataTraceLog pushDataTraceLog) {
        pushDataTraceLogRepository.save(pushDataTraceLog);
        PushDataTraceLog.destroy();
    }
}

pushDataTraceLog 不为 null，pushDataTraceLogService 给出 null 指针

空指针图像

堆栈跟踪给出

java.lang.NullPointerException: null
at com.publicissapient.kpidashboard.apis.pushdata.util.PushDataException.setTraceLog(PushDataException.java:60)
at com.publicissapient.kpidashboard.apis.pushdata.util.PushDataException.<init>(PushDataException.java:52)
at com.publicissapient.kpidashboard.apis.pushdata.service.impl.AuthExposeAPIServiceImpl.validateToken(AuthExposeAPIServiceImpl.java:127)
at com.publicissapient.kpidashboard.apis.pushdata.controller.PushDataController.savePushDataBuilds(PushDataController.java:67)
at com.publicissapient.kpidashboard.apis.pushdata.controller.PushDataController$$FastClassBySpringCGLIB$$61a69129.invoke(<generated>)
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)
at org.springframework.validation.beanvalidation.MethodValidationInterceptor.invoke(MethodValidationInterceptor.java:123)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763)
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708)
at com.publicissapient.kpidashboard.apis.pushdata.controller.PushDataController$$EnhancerBySpringCGLIB$$a6ea830e.savePushDataBuilds(<generated>)
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:498)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1070)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:681)