在使用基于Spring Boot的应用程序启动多个WAR时，我经常遇到异常：
Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.foo.SomeService]: Factory method 'someService' threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'someBean' defined in com.foo.SomeJavaConfig: Post-processing of merged bean definition failed; nested exception is java.lang.NullPointerException
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:599)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1181)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1075)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:513)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:312)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:308)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:761)
at org.springframework.web.SpringServletContainerInitializer.onStartup(SpringServletContainerInitializer.java:169)
at com.ibm.ws.webcontainer.webapp.WebApp.initializeServletContainerInitializers(WebApp.java:2487)
at com.ibm.ws.webcontainer.webapp.WebApp.initialize(WebApp.java:994)
at com.ibm.ws.webcontainer.webapp.WebApp.initialize(WebApp.java:6566)
...
Caused by: java.lang.NullPointerException: null
at com.ibm.ws.classloading.internal.AppClassLoader.getClassSpecificProtectionDomainPrivileged(AppClassLoader.java:367)
at com.ibm.ws.classloading.internal.AppClassLoader.access$000(AppClassLoader.java:64)
at com.ibm.ws.classloading.internal.AppClassLoader$2.run(AppClassLoader.java:351)
at com.ibm.ws.classloading.internal.AppClassLoader$2.run(AppClassLoader.java:348)
at java.security.AccessController.doPrivileged(Native Method)
at com.ibm.ws.classloading.internal.AppClassLoader.getClassSpecificProtectionDomain(AppClassLoader.java:348)
at com.ibm.ws.classloading.internal.AppClassLoader.definePackageAndClass(AppClassLoader.java:325)
at com.ibm.ws.classloading.internal.AppClassLoader.findClass(AppClassLoader.java:271)
at com.ibm.ws.classloading.internal.ParentLastClassLoader.findOrDelegateLoadClass(ParentLastClassLoader.java:80)
at com.ibm.ws.classloading.internal.AppClassLoader.loadClass(AppClassLoader.java:443)
at com.ibm.ws.classloading.internal.ParentLastClassLoader.loadClass(ParentLastClassLoader.java:50)
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)
at java.lang.Class.getDeclaredMethods(Class.java:1975)
at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:613)
at org.springframework.util.ReflectionUtils.doWithLocalMethods(ReflectionUtils.java:489)
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.buildPersistenceMetadata(PersistenceAnnotationBeanPostProcessor.java:431)
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findPersistenceMetadata(PersistenceAnnotationBeanPostProcessor.java:397)
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessMergedBeanDefinition(PersistenceAnnotationBeanPostProcessor.java:333)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyMergedBeanDefinitionPostProcessors(AbstractAutowireCapableBeanFactory.java:1000)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:523)
... 76 common frames omitted
它是非确定性的 - 它发生在所有WAR开始都很好的情况下。 问题在WLP ver：18.0.0.3和19.0.0.3（未在其他上测试）上可重现。 Spring版本4.3.17.RELEASE 对我来说，它看起来像一个错误，但也许有人已经修复它，可能会有所帮助。
您使用什么Java级别来运行此方案？这个问题可能与Java有关，而不是Liberty，这就是我要问的原因。我们已经在一些Java级别中看到了非确定性NullPointerExceptions的一些问题，这些问题在以后的Java级别中已得到修复。
AppClassLoader从18.0.0.3到19.0.0.3有很多变化，但是你提供的堆栈来自18.0.0.3级别的代码，这些代码在很长一段时间内没有变化，所以看起来它不是一个新问题。如果它是Liberty问题，那么在OpenLiberty github上打开一个问题是合适的。您可能需要通过跟踪重现问题，以便IBM更多地进行调试。我建议的跟踪规范是com.ibm.ws.classloading。* = finest：com.ibm.ws.artifact。* = finest