code: @Override
      protected void appendFieldStart( final StringBuffer    buffer,
                                       final String          fieldName )
      {
          appendFieldSeparator( buffer );
  
          if ( isUseFieldNames() && fieldName != null )
          {
              buffer.append( fieldName );
  
              for ( int ii = 0; ii < ( 18 - fieldName.length()); ii++ )
              {
                  buffer.append( " " );
              }
  
              buffer.append( getFieldNameValueSeparator() );
          }
      }
docs: <p>Append the field start to the buffer.</p>
  
  @param buffer  the <code>StringBuffer</code> to populate
  @param fieldName  the field name