code: public void addUniqueAttribute(String name, String value, int flags)
          throws SAXException
      {
          if (m_elemContext.m_startTagOpen)
          {
             
              try
              {
                  final String patchedName = patchName(name);
                  final java.io.Writer writer = m_writer;
                  if ((flags & NO_BAD_CHARS) > 0 && m_xmlcharInfo.onlyQuotAmpLtGt)
                  {
                      // "flags" has indicated that the characters
                      // '>'  '<'   '&'  and '"' are not in the value and
                      // m_htmlcharInfo has recorded that there are no other
                      // entities in the range 32 to 127 so we write out the
                      // value directly
                      
                      writer.write(' ');
                      writer.write(patchedName);
                      writer.write("=\"");
                      writer.write(value);
                      writer.write('"');
                  }
                  else
                  {
                      writer.write(' ');
                      writer.write(patchedName);
                      writer.write("=\"");
                      writeAttrString(writer, value, this.getEncoding());
                      writer.write('"');
                  }
              } catch (IOException e) {
                  throw new SAXException(e);
              }
          }
      }
docs: This method is used to add an attribute to the currently open element.
  The caller has guaranted that this attribute is unique, which means that it
  not been seen before and will not be seen again.
  
  @param name the qualified name of the attribute
  @param value the value of the attribute which can contain only
  ASCII printable characters characters in the range 32 to 127 inclusive.
  @param flags the bit values of this integer give optimization information.