code: private void throwUnrecognizedInputIfAny( StringBuilder builder, int ch ) {
          if( !isWhitespace( builder ) ) {
              throw createException( "Unrecognized input: '" + trim( builder ) + (char)ch + "'" );
          }
          builder.setLength( 0 );
      }
docs: Throw an unrecognized input exception if there content in the StringBuilder.
  
  @param builder the StringBuilder
  @param ch the last character