java中的==和equals

 1 class toString_test 
 2 {
 3     public static void main(String[] args) 
 4     {
 5         String a=new String("today is friday");
 6         String b=new String("today is friday");
 7         System.out.println(a==b);
 8         System.out.println(a.equals(b));
 9     }
10 }