code: private void checkType(String className)
    {
      if (_tc.isEntryEnabled())
      {
        SibTr.entry(_tc, "checkType", new Object[]{this, className});
      }
      
      // Of the classname supplied is not one of
      // com.ibm.wsspi.sib.core.selector.FactoryType or
      // com.ibm.wsspi.sib.core.selector.PrivateFactoryType then an exception is
      // thrown.
      if (!(className.equals("com.ibm.wsspi.sib.core.selector.FactoryType") || className
          .equals("com.ibm.ws.sib.core.selector.PrivateFactoryType")))
      {
        // It would be preferable to throw an Exception version of this, however
        // the exception version
        // is a checked exception which can only be thrown when using reflection
        // to invoke classes.
        // As a result the Error version is thrown.
        IllegalAccessError e = new IllegalAccessError(_nls.getFormattedMessage(
            "INVALID_SUBCLASS_CWSJC0006E", new Object[]{className}, null));
  
        if (_tc.isEventEnabled())
        {
          SibTr.event(_tc, "throwing", e);
        }
  
        if (_tc.isEntryEnabled())
        {
          SibTr.exit(_tc, "checkType", e);
        }
        
        throw e;
      }
  
      if (_tc.isEntryEnabled())
      {
        SibTr.exit(_tc, "checkType");
      }
    }
docs: <p>
  This method checks to ensure that the class being instanciated is one of
  the valid FactoryTypes or subclasses.
  <p>
  
  <p>
  There is currently a single valid subclass of this class:
  <ul>
  <li>com.ibm.wsspi.sib.core.selector.PrivateFactoryType</li>
  </ul>
  It should be noted that the use of that subclass is with prior approval
  from the relevant Jetstream representatives.
  </p>
  
  @param className