What will be the output of String.substring(String.length) : public class Str {

	public static void main(String[] args) {
		
		String str = "abced";
		String s = str.substring(str.length());
		System.out.println(s);
	}

}

index of character 'e' is 4 but i am trying to get whole String from length 5 ,if i execute the above code, why it is not throwing the indexOutOfBounds exception.