我正在使用 @PostCostruct
注释获取初始化方法以在我的 Sprin Boot 应用程序启动时运行代码。
@Service("jobManager")
public class JobManager {
@Autowired
SchedulerFactoryBean scheduler;
@Autowired
InterruttoreService interruttoreService;
@PostConstruct
public void createInitialJobs() throws SchedulerException {
List<Interruttore> interruttori = interruttoreService.findAllSwitches();
for (int i = 0; i < interruttori.size(); i++) {
Interruttore interruttore = interruttori.get(i);
interruttoreService.toggleSwitchOnStartup(interruttore);
}
}
interruttoreService.toggleSwitchOnStartup(interruttore)
在服务类中并且是以下内容(作业管理器在此类中自动连接)
@Override
public void toggleSwitchOnStartup(Interruttore interruttore) {
Date nextTimeout = interruttore.getTimeoutDate();
Date date = new Date();
Date now = new Timestamp(date.getTime());
if (nextTimeout == null) {
nextTimeout = now;
}
int idInterruttore = interruttore.getIdInterruttore();
if(nextTimeout.after(now)){ //c'è un timeout futuro
try { lightOn(idInterruttore);
jobManager.createJob(interruttore, nextTimeout);
} catch (SchedulerException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} else {
shutDown(idInterruttore);
}
}
从这个方法调用 jobManager 时我得到一个 NullPointerException,不知道为什么如果 bean 是在 @PostCostruct 期间创建的...
这是错误的堆栈跟踪
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'interruttoreService': Unsatisfied dependency expressed through field 'jobManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jobManager': Invocation of init method failed; nested exception is java.lang.NullPointerException
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:569)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:349)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1219)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:207)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1128)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1056)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:566)
... 53 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jobManager': Invocation of init method failed; nested exception is java.lang.NullPointerException
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPostProcessor.java:136)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsBeforeInitialization(AbstractAutowireCapableBeanFactory.java:408)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1575)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:207)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1128)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1056)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:566)
... 66 more
Caused by: java.lang.NullPointerException
at it.besmart.service.InterruttoreServiceImpl.toggleSwitchOnStartup(InterruttoreServiceImpl.java:112)
at it.besmart.service.InterruttoreServiceImpl$$FastClassBySpringCGLIB$$907e162e.invoke(<generated>)
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:720)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:655)
at it.besmart.service.InterruttoreServiceImpl$$EnhancerBySpringCGLIB$$e2a6ab4b.toggleSwitchOnStartup(<generated>)
at it.besmart.quartz.JobManager.createInitialJobs(JobManager.java:47)
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.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleElement.invoke(InitDestroyAnnotationBeanPostProcessor.java:365)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMetadata.invokeInitMethods(InitDestroyAnnotationBeanPostProcessor.java:310)
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPostProcessor.java:133)
... 78 more
interruttoreService
是自动正确连接的,因为在启动后它就开始照常工作。
关于jobManager,我只是用这种方式在InterruttoreService.class中@Autowire它
@Service("interruttoreService")
@Transactional
public class InterruttoreServiceImpl implements InterruttoreService {
@Autowired
JobManager jobManager;
....
....
最佳答案
这是紧密耦合的代码(您将 InterruttoreService
注入(inject)到 JobManager
中,同时将 JobManager
注入(inject)到 InterruttoreService
).
为什么不从 JobManager
中删除 InterruttoreService
注入(inject),并让 toggleSwitchOnStartup()
在 @PostCostruct
中完成> 注释方法都在 InterruttoreService
中,直接在 JobManager
已经连接的地方。
关于java - Spring - 使用@PostCostruct 时获取 NullPointErexception,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/40889908/