class MethodeChaine {
  public static void main(String[] arg) {
    String r = "essai";
    String s = "es" + "sai";
    String t = "ESSAI".toLowerCase();
    String u = "est";

    System.out.println("r == s vaut : " + (r == s));
    System.out.println("r == t vaut : " + (r == t));
    System.out.println("r.equals(t) vaut : " + r.equals(t));

    System.out.println("r.compareTo(t) vaut : " + r.compareTo(t));
    System.out.println("r.compareTo(u) vaut : " + r.compareTo(u));
    System.out.println("u.compareTo(r) vaut : " + u.compareTo(r));
  }
}


/*A l'execution, on obtient :
r == s vaut : true
r == t vaut : false
r.equals(t) vaut : true
r.compareTo(t) vaut : 0
r.compareTo(u) vaut : -1
u.compareTo(r) vaut : 1
*/