[WICKET-5135] wicket-atmosphere EventBus constructor throws NullPointerException under invalid state

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 6.6.0
• Fix Version/s: 6.10.0, 7.0.0-M1
• Component/s: wicket-atmosphere
• Assignee: Emond Papegaaij
• Reporter: Hendy Irawan
• Created: 05/Apr/13 18:03
• Updated: 29/Jul/13 07:16
• Resolved: 29/Jul/13 07:16

Description

With invalid configuration, like the WebApplication not yet associated with the servlet, wicket-atmosphere throws NPE.

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'atmosphereEventBus' defined in class id.co.bippo.springapp.AppConfig: Instantiation of bean failed; nested exception is org.springframework.beans.factory.BeanDefinitionStoreException: Factory method [public org.apache.wicket.atmosphere.EventBus id.co.bippo.springapp.AppConfig.atmosphereEventBus()] threw exception; nested exception is java.lang.NullPointerException
        at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:581) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1031) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:927) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:490) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:461) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:314) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:910) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:853) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:768) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:486) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        ... 107 common frames omitted
Caused by: org.springframework.beans.factory.BeanDefinitionStoreException: Factory method [public org.apache.wicket.atmosphere.EventBus id.co.bippo.springapp.AppConfig.atmosphereEventBus()] threw exception; nested exception is java.lang.NullPointerException
        at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:181) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:570) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        ... 117 common frames omitted
Caused by: java.lang.NullPointerException: null
        at org.apache.wicket.atmosphere.EventBus.<init>(EventBus.java:113) ~[wicket-atmosphere-0.8.jar:0.8]
        at id.co.bippo.springapp.SoluvasWebApplication.getEventBus(SoluvasWebApplication.java:296) ~[SoluvasWebApplication.class:na]
        at id.co.bippo.springapp.AppConfig.atmosphereEventBus(AppConfig.java:270) ~[AppConfig.class:na]
        at id.co.bippo.springapp.AppConfig$$EnhancerByCGLIB$$a9c1dc07.CGLIB$atmosphereEventBus$1(<generated>) ~[spring-core-3.2.2.RELEASE.jar:na]
        at id.co.bippo.springapp.AppConfig$$EnhancerByCGLIB$$a9c1dc07$$FastClassByCGLIB$$40a0fc3e.invoke(<generated>) ~[spring-core-3.2.2.RELEASE.jar:na]
        at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228) ~[spring-core-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:286) ~[spring-context-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        at id.co.bippo.springapp.AppConfig$$EnhancerByCGLIB$$a9c1dc07.atmosphereEventBus(<generated>) ~[spring-core-3.2.2.RELEASE.jar:na]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.7.0_15]
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) ~[na:1.7.0_15]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.7.0_15]
        at java.lang.reflect.Method.invoke(Method.java:601) ~[na:1.7.0_15]
        at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:160) ~[spring-beans-3.2.2.RELEASE.jar:3.2.2.RELEASE]
        ... 118 common frames omitted

It should wrap the NPE in a more descriptive error. Suggestion: "Provided Wicket WebApplication is not associated with a ServletContext. Please ensure Wicket application is fully initialized before creating Atmosphere EventBus."

Issue Links

• links to: Stackoverflow thread describing the issue