Creating a Generic Method : Generic Method « Generics « Java Tutorial

public class MainClass {
  static <T, V extends T> boolean isIn(T x, V[] y) {
    for (int i = 0; i < y.length; i++){
      if (x.equals(y[i])){
        return true;
    return false;

  public static void main(String args[]) {
    Integer nums[] = { 1, 2, 3, 4, 5 };

    if (isIn(2, nums)){
      System.out.println("2 is in nums");
    if (!isIn(7, nums)){
      System.out.println("7 is not in nums");

    // Use isIn() on Strings.
    String strs[] = { "one", "two", "three", "four", "five" };

    if (isIn("two", strs))
      System.out.println("two is in strs");

    if (!isIn("seven", strs))
      System.out.println("seven is not in strs");

2 is in nums
7 is not in nums
two is in strs
seven is not in strs

12.3.Generic Method
12.3.1.Creating a Generic Method
12.3.2.Generic Constructors
12.3.3.Generic methods: Max. Min
12.3.4.Generic method maximum returns the largest of three objects
12.3.5.Using generic methods to print array of different types
12.3.6.Wildcard test program