Why can't I read static file in Jetty 8.1.9 - configuration

Question

In /opt/jetty/webapps, I have test.xml under directory w. I have this test.xml in contexts directory:
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE Configure PUBLIC "-//Mort Bay Consulting//DTD Configure//EN" "http://jetty.eclipse.org/configure.dtd">
<Configure class="org.eclipse.jetty.server.handler.ContextHandler">
<Set name="contextPath">/w</Set>
<Set name="resourceBase">/opt/java/webapps/w/</Set>
<Set name="handler">
<New class="org.eclipse.jetty.server.handler.ResourceHandler">
<Set name="welcomeFiles">
<Array type="String">
<Item>test.xml</Item>
</Array>
</Set>
<Set name="cacheControl">max-age=3600,public</Set>
</New>
</Set>
</Configure>
Why Can't I read http://host/w/test.xml?

Answer 1

Your question is a bit confusing, as you mention test.xml twice, and in two different directories.
Anyway, this is a basic example of setting up what you want, using the standard jetty-distribution-8.1.9.v20130131.tar.gz available at download.eclipse.org/jetty/.
The deployable context
Create a file called contexts/w.xml with the following content
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE Configure PUBLIC "-//Mort Bay Consulting//DTD Configure//EN" "http://jetty.eclipse.org/configure.dtd">
<Configure class="org.eclipse.jetty.server.handler.ContextHandler">
<Set name="contextPath">/w</Set>
<Set name="resourceBase"><SystemProperty name="jetty.home" default="."/>/w/</Set>
<Set name="handler">
<New class="org.eclipse.jetty.server.handler.ResourceHandler">
<Set name="welcomeFiles">
<Array type="String">
<Item>test.xml</Item>
<Item>index.html</Item>
</Array>
</Set>
<Set name="cacheControl">max-age=3600,public</Set>
</New>
</Set>
</Configure>
Notes:
${jetty.home} points to whatever your /path/to/jetty-distribution-8.1.9.v20130131/ is
This context points to a directory named ${jetty.home}/w/, which is not in the webapps directory, this is intentional, as the webapps directory is for standalone Java Servlet or Java EE webapps, either in archive form, or in an exploded deployable form. Since you are using ContextHandler and ResourceHandler your deployable does not meet these requirements.
The content
In the ${jetty.home}/w/ directory create a few files.
$ mkdir /path/to/jetty-distribution-8.1.9.v20130131/w
$ echo "<h1>Hello World</h1>" > /path/to/jetty-distribution-8.1.9.v20130131/w/index.html
Testing it
Start Jetty
$ cd /path/to/jetty-distribution-8.1.9.v20130131
$ java -jar start.jar
Open up a browser and test it
http://localhost:8080/w/