Question

I had created a simple JSF2.0 app and it runs fine in my computer, but when I try to run it in Heroku, I get this error:

HTTP ERROR 500

Problem accessing /login.xhtml. Reason:

    Server Error

Caused by:

java.lang.NullPointerException
    at com.sun.faces.context.flash.ELFlash.getFlash(ELFlash.java:93)
    at com.sun.faces.context.flash.ELFlash.getELFlash(ELFlash.java:124)
    at com.sun.faces.context.flash.ELFlash.doPostPhaseActions(ELFlash.java:722)
    at com.sun.faces.lifecycle.Phase.handleAfterPhase(Phase.java:175)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:108)
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:311)
    at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:547)
    at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:481)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:119)
    at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:520)
    at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:227)
    at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:940)
    at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:409)
    at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:186)
    at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:874)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:110)
    at org.eclipse.jetty.server.Server.handle(Server.java:349)
    at org.eclipse.jetty.server.HttpConnection.handleRequest(HttpConnection.java:441)
    at org.eclipse.jetty.server.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:904)
    at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:565)
    at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:217)
    at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:46)
    at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:545)
    at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:43)
    at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:598)
    at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:533)
    at java.lang.Thread.run(Thread.java:636)

So, any solution to this problem?
Thanks in advance.

Answer 1

java.lang.NullPointerException
    at com.sun.faces.context.flash.ELFlash.getFlash(ELFlash.java:93)
    at com.sun.faces.context.flash.ELFlash.getELFlash(ELFlash.java:124)

I don’t recognize the ELFlash#getELFlash() method as part of recent Mojarra implementations. Perhaps you’re using a very early 2.0.0 implementation which has a bug related to this. Upgrading to the latest should fix this problem.

---

but the problem with annotations persists in Heroku

javax.el.PropertyNotFoundException: /login.xhtml @15,55 value="#{user.name}": Target Unreachable, identifier 'user' resolved to null 
    at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:100‌​) 
    at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getConvertedValue(Html‌​BasicInputRenderer.java:95) 

JSF2 annotations will fail if your faces-config.xml is not properly declared conform JSF2 specification. Make sure that the <faces-config> root declaration look like this:

<faces-config
    xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-facesconfig_2_0.xsd"
    version="2.0">

    <!-- config here -->

</faces-config>