find second occurrence of a substring in a string in java

/**
 * @author lautturi.com
 * Java example: get index of second occurrence of substring in java
 */

import java.util.*;

public class Lautturi {
	
	public static void main(String[] args) {
		String str = "hellojavaHijava world";
		// index of first java
		str.indexOf("java");
		// index of second java
		str.indexOf("java", str.indexOf("java") + 1);
		
		System.out.println(str.indexOf("java"));
		System.out.println(str.indexOf("java", str.indexOf("java") + 1));
		
	}
}

output:

5
11