Am I supposed to use the indexOf method?

[son012189]

This is the homework problem word for word.

(Checking substrings) You can check whether a string is a substring of another string by using the indexOf method in the String class. Write your own method for this function. Write a program that prompts the user to enter two strings, and check whether the first string is a substring of the second.

I have already completed this problem and got it to run correctly using the indexOf method.

import java.util.*;
import java.lang.String;

public class CheckingSubstring {
	public static void main(String[] args) {
		Scanner input = new Scanner(System.in);
		System.out.print("Please enter a String: ");
		String string1 = input.next();
		System.out.print("Please enter a second String: ");
		String string2 = input.next();
		if (isSubstring(string1, string2)) {
			System.out.println("The first string is a substring of the second.");
		} else {
			System.out.println("The first string is NOT a substring of the second.");
		}
	}	
		public static boolean isSubstring(String string1, String string2) {
			int position;
			position = string2.indexOf(string1);
			if (position == -1) {
				return false;
			} else {
				return true;
			}				
		}
}

I turned this in last week. My teacher took off 10 points because I used the indexOf method. I believe the problem specifically asks to use the indexOf method and write a method for that function. Did I misunderstand the problem? Am I supposed to use the indexOf method?

[al_Marshy_1981]

Looks like the instructions said that it is possible using the indexOf method but then asks you to implement your own version of indexOf

[son012189]

Oh I see. It would have been better if they worded it differently like this:

Write a indexOf method that checks whether a string is a substring of another string. Write a test program that prompts the user to enter two strings, and check whether the first string is a substring of the second.

[al_Marshy_1981]

Were there others who took your interpretation?

[Momar99]

No from what i see i can see no reason what so ever to use the index it makes no sense what so ever how about you get good at java

[son012189]

@al_Marshy_1981 Yes I think so. I remember the teacher mentioned that a lot of people got this problem wrong before she handed back the homework.

@Momar99 Ok, I appreciate your response, but how about you stop trolling.