jsf recursion jsf-2 primefaces composite-component

Can I nest a composite component in itself recursively?

I have DTO which contains itself (it is nested).

public class MyDTO {

   private SomeData someData;
   private MyDTO nested;

   // getters and setters
}

I created composite component, which is calls itself recursively. I call it like this:

<screen:my-dto-screen dto="#{myDTOBean.myDto}" />

The definition is:

  <composite:interface>
    <composite:attribute name="dto"/>
</composite:interface>
        -- display "someData" here --
    <p:panel rendered="#{cc.attrs.dto.nested != null}" /> -- this acts as recursion bottom --
       <screen:my-dto-screen dto="#{cc.attrs.dto.nested}" />            
    </p:panel>
<composite:implementation>

The real code is not simple as this, but I wrote this in order to give you a simple idea what the problem is about. Everything seems fine, but I get some strange exceptions in view.

javax.servlet.ServletException
javax.faces.webapp.FacesServlet.service(FacesServlet.java:422)
org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:79)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:368)
cayetano.games.common.web.security.OperatorPermissionsFilter.doFilter(OperatorPermissionsFilter.java:74)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:109)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:97)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:100)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:78)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:35)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
cayetano.games.common.web.security.WebUsernamePasswordAuthenticationFilter.actualDoFilter(WebUsernamePasswordAuthenticationFilter.java:65)
cayetano.games.common.web.security.WebUsernamePasswordAuthenticationFilter.doFilter(WebUsernamePasswordAuthenticationFilter.java:43)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:79)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:169)
org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)
org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)

root cause

java.lang.StackOverflowError
java.util.regex.Pattern$Curly.match(Pattern.java:3754)
java.util.regex.Pattern$BmpCharProperty.match(Pattern.java:3383)
java.util.regex.Pattern$Slice.match(Pattern.java:3499)
java.util.regex.Pattern$GroupTail.match(Pattern.java:4244)
java.util.regex.Pattern$BranchConn.match(Pattern.java:4095)
java.util.regex.Pattern$BmpCharProperty.match(Pattern.java:3383)
java.util.regex.Pattern$Branch.match(Pattern.java:4131)
java.util.regex.Pattern$GroupHead.match(Pattern.java:4185)
java.util.regex.Pattern$CharProperty.match(Pattern.java:3362)
java.util.regex.Pattern$Start.match(Pattern.java:3072)
java.util.regex.Matcher.search(Matcher.java:1116)
java.util.regex.Matcher.find(Matcher.java:552)
com.sun.faces.el.ELUtils.isCompositeComponentExpr(ELUtils.java:195)
com.sun.faces.facelets.tag.TagAttributeImpl.getValueExpression(TagAttributeImpl.java:388)
com.sun.faces.facelets.tag.TagAttributeImpl.getValueExpression(TagAttributeImpl.java:351)
com.sun.faces.facelets.tag.jsf.CompositeComponentTagHandler$CompositeComponentRule$CompositeExpressionMetadata.applyMetadata(CompositeComponentTagHandler.java:588)
com.sun.faces.facelets.tag.MetadataImpl.applyMetadata(MetadataImpl.java:81)
javax.faces.view.facelets.MetaTagHandler.setAttributes(MetaTagHandler.java:129)
javax.faces.view.facelets.DelegatingMetaTagHandler.setAttributes(DelegatingMetaTagHandler.java:102)
com.sun.faces.facelets.tag.jsf.CompositeComponentTagHandler.setAttributes(CompositeComponentTagHandler.java:226)
com.sun.faces.facelets.tag.jsf.CompositeComponentTagHandler.applyNextHandler(CompositeComponentTagHandler.java:183)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:98)
javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:98)
javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:98)
javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
com.sun.faces.facelets.tag.composite.ImplementationHandler.apply(ImplementationHandler.java:81)
javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:98)
com.sun.faces.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:93)
com.sun.faces.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:86)
com.sun.faces.facelets.impl.DefaultFacelet.apply(DefaultFacelet.java:152)
com.sun.faces.facelets.tag.jsf.CompositeComponentTagHandler.applyCompositeComponent(CompositeComponentTagHandler.java:349)
com.sun.faces.facelets.tag.jsf.CompositeComponentTagHandler.applyNextHandler(CompositeComponentTagHandler.java:190)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:98)
javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:98)
javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
com.sun.faces.facelets.tag.composite.ImplementationHandler.apply(ImplementationHandler.java:81)
javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:98)
com.sun.faces.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:93)
com.sun.faces.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:86)
com.sun.faces.facelets.impl.DefaultFacelet.apply(DefaultFacelet.java:152)
com.sun.faces.facelets.tag.jsf.CompositeComponentTagHandler.applyCompositeComponent(CompositeComponentTagHandler.java:349)
com.sun.faces.facelets.tag.jsf.CompositeComponentTagHandler.applyNextHandler(CompositeComponentTagHandler.java:190)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:98)
javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:98)
javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:188)
javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
com.sun.faces.facelets.tag.composite.ImplementationHandler.apply(ImplementationHandler.java:81)

Solution

This exception occurred during view build time. The rendered attribute is not evaluated during view build time. It's only evaluated during view render time (and during apply request values phase on input and command components, but that's a story apart). So your approach will end up in an infinite recursion loop which ultimately ends up in a stack overflow in the memory.

Basically, you want to evaluate the condition during view build time instead. So you need a tag/attribute which runs during view build time. One of them is JSTL <c:if>.

<c:if test="#{cc.attrs.dto.nested != null}">
    <p:panel>
       <screen:my-dto-screen dto="#{cc.attrs.dto.nested}" />            
    </p:panel>
</c:if>

However, this does not work if the #{cc.attrs.dto.nested} value is provided by a render-time attribute, so the recursion won't work. Only the top-level component will be shown. You're looking for an iterative approach. Consider looking at an existing JSF tree component, such as PrimeFaces' <p:tree>.