docs: public static void initializeEscapeMap() {
          if (xmlLowValueEscapeStringsInitialized == true) {
              return;
          }
  
          /*
           * synchronize the lazy initialization so things don't break if FindBugs
           * ever becomes multi-threaded (and also so FindBugs doesn't throw a
           * warning about the thread safety of this operation)
           */
          synchronized (escapeInitLockObject) {
              if (xmlLowValueEscapeStringsInitialized == true) {
                  return;
              }
  
              for (int i = 0; i < XML_ALLOWED_LOW_CHARACTER_BOUND; i++) {
                  if (isInvalidXMLCharacter(i)) {
                      String escapedString = String.format("\\u%04x", i);
                      xmlLowValueEscapeStrings[i] = escapedString;
                  } else {
                      xmlLowValueEscapeStrings[i] = null;
                  }
              }
              xmlLowValueEscapeStringsInitialized = true;
          }
      }