code: public void validate() throws ValidateException
     {
        if (this.driverClass != null && (this.connectionUrl == null || this.connectionUrl.trim().length() == 0))
           throw new ValidateException(bundle.requiredElementMissing(XML.ELEMENT_CONNECTION_URL, 
                                                                     this.getClass().getCanonicalName()));
        
        if ((this.driverClass == null || this.driverClass.trim().length() == 0) &&
            (this.dataSourceClass == null || this.dataSourceClass.trim().length() == 0) &&
            (this.driver == null || this.driver.trim().length() == 0))
           throw new ValidateException(bundle.requiredElementMissing(XML.ELEMENT_DRIVER_CLASS, 
                                                                     this.getClass().getCanonicalName()));
     }
docs: {@inheritDoc}