code: public StrBuilder minimizeCapacity() {
          if (buffer.length > length()) {
              final char[] old = buffer;
              buffer = new char[length()];
              System.arraycopy(old, 0, buffer, 0, size);
          }
          return this;
      }
docs: Minimizes the capacity to the actual length of the string.
  
  @return this, to enable chaining