class T {
  Calculator calc;

  public void testAdd() {
    assertEqual(calc.add(2,4),7,"add(3,4)");
    assertEqual(calc.add(0,4),4,"add(0,4)");
  }

  public void testMult() {
    assertEqual(calc.mult(0,4),0,"mult(0,4)");
  }

  public static void main(String[] args) {
    T tester = new T();
    tester.setUp();
    tester.testAdd();
    tester.testMult();
    tester.tearDown();
  }

  // support code

  public void assertEqual(int result, int expecting, String msg) {
	if ( result!=expecting ) {
	    System.err.println("failure: "+msg+"="+result+"; expecting="+expecting);
	}
  }

  public void setUp() { calc = new Calculator(); }
  public void tearDown() { calc=null; }
}