Possible bug (NPE) with @Factory methods and null for Page Scoped variables (2.0.3.CR1)
viviansteller.vivian.steller.uni-ulm.de Jul 15, 2008 6:15 AMGood morning,
I'm not sure but I think I found a bug regarding the behavior of @Factory methods: outjecting null to the page context leads to an NullPointerException.
Consider this code:
@Name("courseFactory") @Scope(APPLICATION) public class CourseFactory { @Factory(value = COURSE, autoCreate = true, scope = PAGE) public Course loadCourse() { ... return null; } }
When asking for #{course} in a facelets page, a NPE is thrown. See the stack trace below.
However, not using a @Factory method with return value works without any exception:
@Name("courseFactory") @Scope(APPLICATION) public class CourseFactory { @Out(scope = PAGE, required = false) private Course course; @Factory(value = COURSE, autoCreate = true) public void loadCourse() { ... course = null; } }
In my opinion both types of @Factory notations should behave the same, right?
Maybe this bug is also related to JBSEAM-81?
Thanks for any comments.
Here is the stack trace:
06:12:50,977 ERROR [STDERR] 15.07.2008 06:12:50 com.sun.facelets.FaceletViewHandler handleRenderException SCHWERWIEGEND: Error Rendering View[/teaching/lecture.xhtml] java.lang.NullPointerException at javax.faces.component.UIComponentBase$AttributesMap.put(UIComponentBase.java:1602) at javax.faces.component.UIComponentBase$AttributesMap.put(UIComponentBase.java:1496) at org.jboss.seam.contexts.PageContext.set(PageContext.java:97) at org.jboss.seam.Component.handleFactoryMethodResult(Component.java:1948) at org.jboss.seam.Component.getInstanceFromFactory(Component.java:1930) at org.jboss.seam.Component.getInstance(Component.java:1866) at org.jboss.seam.Component.getInstance(Component.java:1843) at org.jboss.seam.Component.getInstanceInAllNamespaces(Component.java:2192) at org.jboss.seam.Component.getValueToInject(Component.java:2144) at org.jboss.seam.Component.injectAttributes(Component.java:1601) at org.jboss.seam.Component.inject(Component.java:1419) at org.jboss.seam.core.BijectionInterceptor.aroundInvoke(BijectionInterceptor.java:45) at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) at org.jboss.seam.core.MethodContextInterceptor.aroundInvoke(MethodContextInterceptor.java:42) at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) at org.jboss.seam.intercept.RootInterceptor.invoke(RootInterceptor.java:107) at org.jboss.seam.intercept.JavaBeanInterceptor.interceptInvocation(JavaBeanInterceptor.java:166) at org.jboss.seam.intercept.JavaBeanInterceptor.invoke(JavaBeanInterceptor.java:102) at de.uniulm.zsp.factory.LectureFactory_$$_javassist_5.loadLecture(LectureFactory_$$_javassist_5.java) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at org.jboss.seam.util.Reflections.invoke(Reflections.java:21) at org.jboss.seam.util.Reflections.invokeAndWrap(Reflections.java:125) at org.jboss.seam.Component.callComponentMethod(Component.java:2092) at org.jboss.seam.Component.getInstanceFromFactory(Component.java:1929) at org.jboss.seam.Component.getInstance(Component.java:1866) at org.jboss.seam.Component.getInstance(Component.java:1843) at org.jboss.seam.Namespace.getComponentInstance(Namespace.java:55) at org.jboss.seam.Namespace.getComponentInstance(Namespace.java:50) at org.jboss.seam.el.SeamELResolver.resolveBase(SeamELResolver.java:166) at org.jboss.seam.el.SeamELResolver.getValue(SeamELResolver.java:53) at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:53) at com.sun.faces.el.FacesCompositeELResolver.getValue(FacesCompositeELResolver.java:64) at org.jboss.el.parser.AstIdentifier.getValue(AstIdentifier.java:44) at org.jboss.el.parser.AstValue.getValue(AstValue.java:63) at org.jboss.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186) at com.sun.facelets.el.TagValueExpression.getValue(TagValueExpression.java:71) at javax.faces.component.UIOutput.getValue(UIOutput.java:173) at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getValue(HtmlBasicInputRenderer.java:189) at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.getCurrentValue(HtmlBasicRenderer.java:320) at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeEnd(HtmlBasicRenderer.java:200) at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:833) at org.ajax4jsf.renderkit.RendererBase.renderChild(RendererBase.java:286) at org.ajax4jsf.renderkit.RendererBase.renderChildren(RendererBase.java:262) at org.ajax4jsf.renderkit.RendererBase.renderChild(RendererBase.java:284) at org.richfaces.renderkit.html.PanelRenderer.doEncodeBegin(PanelRenderer.java:189) at org.richfaces.renderkit.html.PanelRenderer.doEncodeBegin(PanelRenderer.java:148) at org.ajax4jsf.renderkit.RendererBase.encodeBegin(RendererBase.java:101) at javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:785) at javax.faces.component.UIComponent.encodeAll(UIComponent.java:884) at javax.faces.component.UIComponent.encodeAll(UIComponent.java:892) at javax.faces.component.UIComponent.encodeAll(UIComponent.java:892) at com.sun.facelets.FaceletViewHandler.renderView(FaceletViewHandler.java:592) at org.ajax4jsf.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:108) at org.ajax4jsf.application.AjaxViewHandler.renderView(AjaxViewHandler.java:189) at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:106) at com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:251) at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:144) at javax.faces.webapp.FacesServlet.service(FacesServlet.java:245) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83) at org.jboss.seam.debug.hot.HotDeployFilter.doFilter(HotDeployFilter.java:68) at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) at org.jboss.seam.web.MultipartFilter.doFilter(MultipartFilter.java:85) at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64) at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64) at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) at org.jboss.seam.web.RedirectFilter.doFilter(RedirectFilter.java:45) at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) at org.ajax4jsf.webapp.BaseXMLFilter.doXmlFilter(BaseXMLFilter.java:154) at org.ajax4jsf.webapp.BaseFilter.handleRequest(BaseFilter.java:260) at org.ajax4jsf.webapp.BaseFilter.processUploadsAndHandleRequest(BaseFilter.java:366) at org.ajax4jsf.webapp.BaseFilter.doFilter(BaseFilter.java:493) at org.jboss.seam.web.Ajax4jsfFilter.doFilter(Ajax4jsfFilter.java:60) at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) at org.jboss.seam.web.LoggingFilter.doFilter(LoggingFilter.java:58) at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) at org.jboss.seam.servlet.SeamFilter.doFilter(SeamFilter.java:158) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175) at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:179) at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:84) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104) at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:156) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:241) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:580) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) at java.lang.Thread.run(Thread.java:613)