[MYFACES-4379] FacesConfigUnmarshallerImpl - navigation-rules, view-param parsing

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3-next-M3, 2.3-next-M4, 4.0.0-RC1
• Fix Version/s: 2.3-next-M5, 4.0.0-RC1
• Component/s: General
• Assignee: Thomas Andraschko
• Reporter: Milan Siebenbürger
• Created: 26/Jan/21 14:15
• Updated: 27/Jan/21 09:14
• Resolved: 27/Jan/21 08:08

Description

Hello,

could you please check FacesConfigUnmarshallerImpl, we discovered some issues in navigation rules parsing, especially view-param / redirect-param. Is there is something wrong on our side?

The specific configuration of navigation rules xml looks like this

<redirect>
   <view-param>
      <name>cid</name>
      <value></value>
   </view-param>
</redirect>

Issue 1. - viewParams are not handled correctly:

          onChild("view-param", n, (cn) -> {
                ViewParamImpl vp = new ViewParamImpl();
                r.addViewParam(vp);
                onChild("name", cn, (ccn) -> { vp.setName(ccn.getTextContent()); });
                onChild("value", cn, (ccn) -> { vp.setValue(ccn.getTextContent()); });
            });

If I understand it correctly, empty ViewParamImpl si created, added to r (RedirectImpl), and after that it is filled with xml values.

In RedirectImpl, method addViewParam, is ViewParam attribute transformed to key/value combination and added to local HashMap. Because it is empty (yet), empty key is created in local HashMap, and no values are filled.

public void addViewParam(ViewParamImpl viewParam)
{
    if (viewParams == null)
    {
        viewParams = new HashMap<>(3, 1f);
    }
    List<String> params = viewParams.computeIfAbsent(viewParam.getName(), k -> new ArrayList<>(3));
    params.add(viewParam.getValue());
}

Rest of implementation is irrelevant.

What do you think about changing order of command like that ->

     onChild("view-param", n, (cn) -> {
                ViewParamImpl vp = new ViewParamImpl();
               
                onChild("name", cn, (ccn) -> { vp.setName(ccn.getTextContent()); });
                onChild("value", cn, (ccn) -> { vp.setValue(ccn.getTextContent()); });
                 r.addViewParam(vp); // moved down
            });

same, with redirect-param .. and maybe others ..

 

Issue 2. - empty value in view-param parameter

As is seen in example above, we need to pass empty value to view-param. But method getTextContent returns null as a value.

After that, NPE is throwed:

java.lang.NullPointerException: null
	at java.net.URLEncoder.encode(URLEncoder.java:204)
	at org.apache.myfaces.context.servlet.ServletExternalContextImpl.encodeURL(ServletExternalContextImpl.java:990)
	at org.apache.myfaces.context.servlet.ServletExternalContextImpl.encodeRedirectURL(ServletExternalContextImpl.java:455)
	at javax.faces.context.ExternalContextWrapper.encodeRedirectURL(ExternalContextWrapper.java:101)
	at javax.faces.context.ExternalContextWrapper.encodeRedirectURL(ExternalContextWrapper.java:101)
	at org.apache.myfaces.application.ViewHandlerImpl.getRedirectURL(ViewHandlerImpl.java:175)
	at javax.faces.application.ViewHandlerWrapper.getRedirectURL(ViewHandlerWrapper.java:142)
	at org.apache.webbeans.jsf.ConversationAwareViewHandler.getRedirectURL(ConversationAwareViewHandler.java:89)
	at javax.faces.application.ViewHandlerWrapper.getRedirectURL(ViewHandlerWrapper.java:142)

 Is it possible to pass empty value somehow?

Thanks

Milan Siebenbürger