tomcat6 servlet error requested resource is not available

java-tomcat6-servlet-error

"The requested resource (/ProjectName/servlet/ClassName) is not available."

vi workspace/Projectname/WebContent/WEB-INF/web.xml

For each servlet you want to call, provide a pair of tags like the following,
NOTE: all your <servlet> tags are declared before your <servlet-mapping> tags!
NOTE: <servlet-class> tag contains the fully qualified name of your class, Package and everything (not including .class)

<servlet>
    <servlet-name>HelloWorld</servlet-name>
    <servlet-class>your.package.name.HelloWorld</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>HelloWorld</servlet-name>
    <url-pattern>/hello</url-pattern>
</servlet-mapping>

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Example from Eclipse's auto generated Servlet (default package)

  <servlet>
    <description></description>
    <display-name>MyServlet</display-name>
    <servlet-name>MyServlet</servlet-name>
    <servlet-class>MyServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>MyServlet</servlet-name>
    <url-pattern>/MyServlet</url-pattern>
  </servlet-mapping>

NOTE: it's easier to let Eclipse build the xml by choosing to add Servlet...
NOTE: after manually fixing a Dynamic Web Project you may have to restart Eclipse

context.xml?

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STRANGELY - ADDING  A SECOND ONE MANUALLY THIS WAY WORKED...

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
  <display-name>ReadFile</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
  <servlet>
    <description></description>
    <display-name>MyServlet</display-name>
    <servlet-name>MyServlet</servlet-name>
    <servlet-class>MyServlet</servlet-class>
  </servlet>
 <servlet>
    <description></description>
    <display-name>ReadFile</display-name>
    <servlet-name>ReadFile</servlet-name>
    <servlet-class>ReadFile</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>MyServlet</servlet-name>
    <url-pattern>/MyServlet</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>ReadFile</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>


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WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'source' to
 'org.eclipse.jst.jee.server: (project name)' did not find a matching property.


Double click on your tomcat server. It will open the server configuration.
Under server options check ‘Publish module contents to separate XML files’ checkbox. Restart your server.