code: private static void initPrefixHandlers()
      {
          PrefixHandlerConfig[] prefixHandlers = ConfigUtil.getConfig().getPrefixHandlers();
          if ( prefixHandlers == null )
          {
              return;
          }
          for ( int i = 0; i < prefixHandlers.length; i++ )
          {
              try
              {
                  Class prefixClass = Class.forName( prefixHandlers[i].getHandlerClass() );
                  String name = prefixHandlers[i].getName();
                  if ( name == null || name.equals( "" ) )
                  {
                      _log.warn( "The name for the prefix handler '" + prefixHandlers[i].getHandlerClass()
                              + "' must not be null" );
                      continue;
                  }
                  Object o = prefixClass.newInstance();
                  if ( !( o instanceof RequestParameterHandler ) )
                  {
                      _log.warn( "The class '" + prefixHandlers[i].getHandlerClass()
                              + "' must be an instance of RequestParameterHandler" );
                      continue;
                  }
                  ProcessPopulate.registerPrefixHandler( name, ( RequestParameterHandler ) o );
              }
              catch ( ClassNotFoundException e )
              {
                  _log.warn( "Class '" + prefixHandlers[i].getHandlerClass() + "' not found", e );
              }
              catch ( IllegalAccessException e )
              {
                  _log.warn( "Illegal access on Class '" + prefixHandlers[i].getHandlerClass() + "'", e );
  
              }
              catch ( InstantiationException e )
              {
                  _log.warn( "InstantiationException on Class '" + prefixHandlers[i].getHandlerClass() + "'",
                          e.getCause() );
              }
          }
      }
docs: This method will initialize all of the PrefixHandlers registered in the netui config.
  The prefix handlers are registered with ProcessPopulate and are typically implemented as
  public inner classes in the tags that require prefix handlers.