Java 接口实现计算器：灵活多样的运算方法

public interface Calculator { int calculate(int x, int y); }

public class Add implements Calculator { public int calculate(int x, int y) { return x + y; } }

public class Substract implements Calculator { public int calculate(int x, int y) { return x - y; } }

public class Multiply implements Calculator { public int calculate(int x, int y) { return x * y; } }

public class Divide implements Calculator { public int calculate(int x, int y) { if (y == 0) { throw new ArithmeticException('Cannot divide by zero'); } return x / y; } }

public class CalculatorMain { public static void main(String[] args) { int x = 10; int y = 2;

    Calculator calculator = new Add();
    System.out.println(calculator.calculate(x, y));

    calculator = new Substract();
    System.out.println(calculator.calculate(x, y));

    calculator = new Multiply();
    System.out.println(calculator.calculate(x, y));

    calculator = new Divide();
    System.out.println(calculator.calculate(x, y));
}

}