How to Upgrade project from Jsf 2.2 to Jsf 2.3 in Eclipse

Question

Currently I am working on project using Primefaces 6.1 and Jsf 2.2 using Eclipse. Now I want to upgrade project from Jsf 2.2 to Jsf 2.3 . But I am facing some issues after replacing Jsf's jar files with javax.faces-2.3.2.jar , javax.faces-api-2.3.jar , jsf-impl-2.2.3.jar .

I know this issue is already raised in Issues using Websocket in Jsf 2.3 but here in my case, all jar files/ libraries are already added. And my question is:
Which Editor is currently available for Jsf 2.3 support?
I think Eclipse is supporting till jsf 2.2 only

Issues:
1. Eclipse is unable to recognize new Tags like
2. After running project, I am getting error message

14:41:37,978 ERROR [io.undertow.request] (default task-10) UT005023: Exception handling request to /haag/user/push.xhtml: javax.servlet.ServletException: /user/push.xhtml @21,63 <f:websocket> Tag Library supports namespace: http://xmlns.jcp.org/jsf/core, but no tag was defined for name: websocket
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:671)
    at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85)
    at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62)
    at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36)
    at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131)
    at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57)
    at io.undertow.server.handlers.DisableCacheHandler.handleRequest(DisableCacheHandler.java:33)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.security.handlers.AuthenticationConstraintHandler.handleRequest(AuthenticationConstraintHandler.java:53)
    at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46)
    at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64)
    at io.undertow.servlet.handlers.security.ServletSecurityConstraintHandler.handleRequest(ServletSecurityConstraintHandler.java:59)
    at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60)
    at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77)
    at io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50)
    at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at org.wildfly.extension.undertow.deployment.GlobalRequestControllerHandler.handleRequest(GlobalRequestControllerHandler.java:68)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:292)
    at io.undertow.servlet.handlers.ServletInitialHandler.access$100(ServletInitialHandler.java:81)
    at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:138)
    at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135)
    at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48)
    at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43)
    at org.wildfly.extension.undertow.security.SecurityContextThreadSetupAction.lambda$create$0(SecurityContextThreadSetupAction.java:105)
    at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
    at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
    at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
    at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
    at org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1508)
    at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:272)
    at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81)
    at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:104)
    at io.undertow.server.Connectors.executeRootHandler(Connectors.java:326)
    at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:812)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
Caused by: javax.faces.view.facelets.TagException: /user/push.xhtml @21,63 <f:websocket> Tag Library supports namespace: http://xmlns.jcp.org/jsf/core, but no tag was defined for name: websocket
    at com.sun.faces.facelets.compiler.CompilationManager.pushTag(CompilationManager.java:311)
    at com.sun.faces.facelets.compiler.SAXCompiler$CompilationHandler.startElement(SAXCompiler.java:268)
    at org.apache.xerces.parsers.AbstractSAXParser.startElement(AbstractSAXParser.java:498)
    at org.apache.xerces.parsers.AbstractXMLDocumentParser.emptyElement(AbstractXMLDocumentParser.java:180)
    at org.apache.xerces.impl.dtd.XMLDTDValidator.emptyElement(XMLDTDValidator.java:811)
    at org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanStartElement(XMLNSDocumentScannerImpl.java:275)
    at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(XMLDocumentFragmentScannerImpl.java:1653)
    at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:324)
    at org.apache.xerces.parsers.XML11Configuration.parse(XML11Configuration.java:875)
    at org.apache.xerces.parsers.XML11Configuration.parse(XML11Configuration.java:798)
    at org.apache.xerces.parsers.XMLParser.parse(XMLParser.java:108)
    at org.apache.xerces.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1198)
    at org.apache.xerces.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:564)
    at org.apache.xerces.jaxp.SAXParserImpl.parse(SAXParserImpl.java:298)
    at javax.xml.parsers.SAXParser.parse(SAXParser.java:195)
    at com.sun.faces.facelets.compiler.SAXCompiler.doCompile(SAXCompiler.java:464)
    at com.sun.faces.facelets.compiler.SAXCompiler.doCompile(SAXCompiler.java:440)
    at com.sun.faces.facelets.compiler.Compiler.compile(Compiler.java:124)
    at com.sun.faces.facelets.impl.DefaultFaceletFactory.createFacelet(DefaultFaceletFactory.java:481)
    at com.sun.faces.facelets.impl.DefaultFaceletFactory.access$100(DefaultFaceletFactory.java:106)
    at com.sun.faces.facelets.impl.DefaultFaceletFactory$1.newInstance(DefaultFaceletFactory.java:199)
    at com.sun.faces.facelets.impl.DefaultFaceletFactory$1.newInstance(DefaultFaceletFactory.java:197)
    at com.sun.faces.facelets.impl.DefaultFaceletCache$1.newInstance(DefaultFaceletCache.java:86)
    at com.sun.faces.facelets.impl.DefaultFaceletCache$1.newInstance(DefaultFaceletCache.java:81)
    at com.sun.faces.util.ExpiringConcurrentCache$1.call(ExpiringConcurrentCache.java:99)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at com.sun.faces.util.ExpiringConcurrentCache.get(ExpiringConcurrentCache.java:114)
    at com.sun.faces.facelets.impl.DefaultFaceletCache.getFacelet(DefaultFaceletCache.java:124)
    at com.sun.faces.facelets.impl.DefaultFaceletCache.getFacelet(DefaultFaceletCache.java:63)
    at com.sun.faces.facelets.impl.DefaultFaceletFactory.getFacelet(DefaultFaceletFactory.java:295)
    at com.sun.faces.facelets.impl.DefaultFaceletFactory.getFacelet(DefaultFaceletFactory.java:239)
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.buildView(FaceletViewHandlingStrategy.java:1000)
    at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:99)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:219)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:659)
    ... 42 more

Answer 1

1. Correct. It takes some time for Eclipse to implement new features. Using the latest Red Hat Developer Studio, which is based on Eclipse, I have the same issue, it still doesn't recognise the new websocket tag in Eclipse, but you can use it in your project. I'm also using JSF 2.3 in my project. Log an issue at Eclipse if you want to speed up the process.

2. The error is related to your server. I guess you use WildFly or EAP, based on your logs.

To solve this:

• follow this guide: https://docs.jboss.org/author/display/WFLY10/JSF+Configuration#JSFConfiguration-ConfiguringaJSFapptouseanondefaultJSFimplementation
• and this guide for splitting the jars: How to install one jar variant of JSF (javax.faces.jar) on WildFly

Very important: if you don't configure your wildfly or your application to explicitly use 2.3, it still won't work.

On server level through CLI: /subsystem=jsf/:write-attribute(name=default-jsf-impl-slot,value=<JSF_IMPL_NAME>-<JSF_VERSION>)

On application level through web.xml:

<context-param>
  <param-name>org.jboss.jbossfaces.JSF_CONFIG_NAME</param-name>
  <param-value>myfaces-2.2.12</param-value>
</context-param>

Good luck