docs: public static StringBuilder toStringBuilder(Collection<? extends Object> collection, String delimiter) {
          StringBuilder sb = new StringBuilder(collection.size() * 20);
          for (Iterator<? extends Object> it = collection.iterator(); it.hasNext();) {
              Object cs = it.next();
              sb.append(cs);
              if (it.hasNext()) {
                  sb.append(delimiter);
              }
          }
          return sb;
      }