docs: public StringGrabber substring(int startIdx, int endIndex) {
  		if (startIdx < 0) {
  			startIdx = 0;
  		}
  		if (endIndex > length() - 1) {
  			endIndex = length() - 1;
  		}
  
  		sb = new StringBuilder(substringInternally(startIdx, endIndex));
  		return StringGrabber.this;
  	}