Java에서 Int가 Null인지 확인

public class Main {
  public static void main(String[] args) {
    int id = 0; // Primitve DataTypes..
    Integer ID = new Integer(5);
    System.out.println("Primitive integer : " + id);
    // we cannot check for Null Property
    System.out.println("Integer Object : " + ID);
    // We can check for Null Property..

    if (ID == null) {
      System.out.println("Integer Is  Null");
    } else {
      System.out.println("Integer Is  Not Null");
    }
  }
}

Primitive integer : 0
Integer Object : 5
Integer Is  Not Null