code: private void appendVersionPiece(StringBuilder sb, String pc) {
          if ((pc != null) && !pc.isEmpty()) {
              pc = pc.trim();
              
              if (sb.length() > 0) {
                  sb.append(".");
              }
              
              sb.append(StringUtils.isNumeric(pc) ? pc : "0");
          }
      }
docs: Append the version piece to the version # under construction.
  
  @param sb String builder receiving the version under construction.
  @param pc The version piece to add. If null, it is ignored. If non-numeric, a value of "0" is
  used.