How to use

CharSequenceUtils$1

in

org.netbeans.modules.cnd.utils.cache

@Override
public String toString() {
  return new StringBuilder(length()).append(s1).append(s2).toString();
}

@Override
public CharSequence subSequence(int start, int end) {
  return new StringBuilder(length()).append(s1).append(s2).subSequence(start, end);
}