title: XJC (custom HelloWorld) plugin not loaded
body: <p>I have created a jar with a <em>Hello World</em> xjc plugin. </p>
  
  <pre><code>package org.czentral.xjc;
  ...
  
  public class HelloWorldPlugin extends Plugin {
  
      @Override
      public String getOptionName() {
          return "Xhello-world";
      }
  
      @Override
      public String getUsage() {
          return " -Xhello-world: Hello World plugin.";
      }
  
      @Override
      public boolean run(Outline otln, Options optns, ErrorHandler eh) throws SAXException {
          System.out.println("Hello World running.");
          return true;
      }
  
  }
  </code></pre>
  
  <p>I have added a <code>META-INF/sevices/com.sun.tools.xjc.Plugin</code> file with a single line telling:</p>
  
  <pre><code>org.czentral.xjc.HelloWorldPlugin
  </code></pre>
  
  <p>After this I expected my <em>usage</em> line to show up in the help output for:</p>
  
  <pre><code>xjc -classpath XJC-Hello.jar -extension
  </code></pre>
  
  <p>Copying the jar to jdk/jre/lib/ext folder yields no results either. Neither does adding the jar to CLASSPATH environment.</p>
  
  <p>I have checked the <code>jaxb-ri</code> sources and the plugins implemented in the <code>/com/sun/tools/xjc/addon/*</code> folder do not really show any additional requirements a plugin has to satisfy.</p>