code: protected boolean validateJarFile(File jarfile)
          throws IOException {
  
          if (triggers == null)
              return (true);
          JarFile jarFile = new JarFile(jarfile);
          for (int i = 0; i < triggers.length; i++) {
              Class clazz = null;
              try {
                  if (parent != null) {
                      clazz = parent.loadClass(triggers[i]);
                  } else {
                      clazz = Class.forName(triggers[i]);
                  }
              } catch (Throwable t) {
                  clazz = null;
              }
              if (clazz == null)
                  continue;
              String name = triggers[i].replace('.', '/') + ".class";
              if (log.isDebugEnabled())
                  log.debug(" Checking for " + name);
              JarEntry jarEntry = jarFile.getJarEntry(name);
              if (jarEntry != null) {
                  log.info("validateJarFile(" + jarfile + 
                      ") - jar not loaded. See Servlet Spec 2.3, "
                      + "section 9.7.2. Offending class: " + name);
                  jarFile.close();
                  return (false);
              }
          }
          jarFile.close();
          return (true);
  
      }
docs: Check the specified JAR file, and return <code>true</code> if it does
  not contain any of the trigger classes.
  
  @param jarfile The JAR file to be checked
  
  @exception IOException if an input/output error occurs