Java code please

/** * Write a recursive function that finds the index of s2 in s1. Do not use any * string functions except for .length(), .equals(), and .substring(). Do not use * any loops, or any data structures. * @param s1 * @param s2 * @return Returns the index of the first time that * s2 appears in s1 or -1 if s2 is not contained * in s1. */ public static int indexOf(String s1, String s2) {}

sample outputs System.out.println(Recursion.indexOf("Hello", "lo")); // 3 Stack stack = new Stack(); stack.push(2); stack.push(3); stack.push(4); stack.push(55); stack.push(6); stack.push(17); stack.push(8);

Should use only static methods