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Re: [jetty-users] AbstractHttpConnection's NullPointerException
You are applying servlet concepts to the ResourceHandler, which is based on the Jetty internal Handler concepts, which are not a strict participant in the servlet infrastructure.  They are more fundamental.  In fact, the entire servlet layer is built on-top of the Handler layer in Jetty.

The ResourceHandler needs a pathInfo to know what resource you are requesting from the resourceBase.
If you want to use the ResourceHandler, don't use the WebAppContext, use the ContextHandler instead.  Different behavior.

If you want to serve static content and servlets, here's 2 choices.

1) use the DefaultServlet in your webapp (war).  It is built-into the servlet support of jetty.
See ${jetty.home}/etc/webdefault.xml to see its default configuration.
Note: the DefaultServlet itself uses the Resource framework to serve static content.

2) split the Jetty handling of your static content from the webapp handling your dynamic content.
This can be accomplished with 2 deployable apps.  1 using the ContextHandler for static content, and the other using WebAppContext for your webapp.

--
Joakim Erdfelt <joakim@xxxxxxxxxxx>
Developer advice, services and support
from the Jetty & CometD experts


On Fri, Jan 25, 2013 at 1:47 PM, Libor Jelinek <ljelinek@xxxxxxxxxxx> wrote:
Hi Joakim!
I agree that more proper is just ContextHandler if I plan to serve just static files but how this could be invalid to use WebAppContext if WebAppContext is indirect child of ContextHandler?

You mention that this NPE is caused by not having set pathInfo correctly but it's absolutelly valid to have null pathInfo() [1]. Root context path (/) couldn't have pathInfo (/somePathInfo) by nature since otherwise it may collides with another servlet (with servlet deployed at somePathInfo context path to continue my example).

[1] http://docs.oracle.com/javaee/6/api/javax/servlet/http/HttpServletRequest.html#getPathInfo()

By the way I think that well-written app should never thrown NPE to the end-user (or end-developer). If code doesn't except null it should check for it before and throw high level exception explaining what's wrong.

Do you think it will be helpful to file a enhancement bug for this (to produce more human error in this case)?

--
Hezky den / Have a nice day
Libor JELÍNEK

VIRTAGE SOFTWARE // software - design - web
Lucni 542 // 285 04 Uhlirske Janovice // Czech Republic
support: +420 315 555 488 // cell: +420 777 205 142
email/jabber: ljelinek@xxxxxxxxxxx // web: www.virtage.com

Visit our developer adventures at http://devblog.virtage.com!


On Fri, Jan 25, 2013 at 5:57 PM, Joakim Erdfelt <joakim@xxxxxxxxxxx> wrote:
That NPE is on ...


So that means your the pathInfo is not set right.
Looking at your configuration, you have it defined as a full blown WebAppContext, when you are only using low level handler stuff.

Try this for the top level XML element instead ...

<Configure class="org.eclipse.jetty.server.handler.ContextHandler">

per the example in our distribution ...


--
Joakim Erdfelt <joakim@xxxxxxxxxxx>
Developer advice, services and support
from the Jetty & CometD experts


On Fri, Jan 25, 2013 at 2:33 AM, Libor Jelinek <ljelinek@xxxxxxxxxxx> wrote:
Hello all!
In very simple (maybe simplest as its just ResourceHandler) scenario to serve static plain HTML files I'm facing NPE with jetty-8.1.8.v20121106.

Very basic $JETTY_HOME/my-context.xml:

<?xml version="1.0"  encoding="ISO-8859-1"?>
<!DOCTYPE Configure PUBLIC "-//Jetty//Configure//EN" "http://www.eclipse.org/jetty/configure.dtd">

<Configure class="org.eclipse.jetty.webapp.WebAppContext">
<Set name="contextPath">/my-context</Set>
<Set name="resourceBase">/home/libor/Ubuntu One/SYSA/nice-error-pages/</Set>
  
<Set name="handler">
<New class="org.eclipse.jetty.server.handler.ResourceHandler">
 <Set name="welcomeFiles">
<Array type="String">
 <Item>index.html</Item>
</Array>
 </Set>
 <Set name="cacheControl">max-age=3600,public</Set>
</New>
</Set>  
</Configure>

Produces HTTP 500 Internal Server error with the following details from log file:

2013-01-25 10:05:03.811:WARN:oejs.AbstractHttpConnection:/nice404/
java.lang.NullPointerException
at org.eclipse.jetty.server.handler.ResourceHandler.handle(ResourceHandler.java:403)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1074)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:382)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:193)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1006)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:135)
at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:255)

NPE is caused by something in <Set name="handler"> block because removing or commenting it out prevents crash.

What's wrong? Thanks for any suggestions.

--
Hezky den / Have a nice day
Libor JELÍNEK

VIRTAGE SOFTWARE // software - design - web
Lucni 542 // 285 04 Uhlirske Janovice // Czech Republic
support: +420 315 555 488 // cell: +420 777 205 142
email/jabber: ljelinek@xxxxxxxxxxx // web: www.virtage.com

Visit our developer adventures at http://devblog.virtage.com!

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