@Test public void add2() { int actual = calculator.add(12, 12); int expected = 25; assertNotEquals(expected, actual); }
public int add(int n1,int n2) { return n1+n2; }
Calculator { public int add(int n1,int n2) { return n1+n2; } }
Calculator { public int add(int n1,int n2) { return n1+n2; }  }
Calculator { public int add(int n1,int n2) { return n1+n2; }  int add(int n1,int n2); }
Calculator { public int add(int n1,int n2) { return n1+n2; }  int add(int n1,int n2);  }