在实验三中曾经实现过日期类MyDate，它包含一个含参数的构造方法MyDate(intyear,intmonth,intday)、以及三个相应的设置方法setXXX(intarg)。1.现编写一个自定义的异常InvalidDateException。当构造方法或设置方法接受的参数不符合实际要求时，抛出一个这个异常的实例。2.在main方法中分别包含以下代码，捕获并打印异常信息：MyDated1=newMyDate(-1,13,32);MyDated2=newMyDate();d2.setDay(100);

以下是实现代码：

class InvalidDateException extends Exception {
    public InvalidDateException(String message) {
        super(message);
    }
}

class MyDate {
    private int year;
    private int month;
    private int day;

    public MyDate(int year, int month, int day) throws InvalidDateException {
        if (year <= 0 || month <= 0 || month > 12 || day <= 0 || day > 31) {
            throw new InvalidDateException("Invalid date");
        }
        this.year = year;
        this.month = month;
        this.day = day;
    }

    public MyDate() {
        this.year = 1;
        this.month = 1;
        this.day = 1;
    }

    public void setYear(int year) throws InvalidDateException {
        if (year <= 0) {
            throw new InvalidDateException("Invalid year");
        }
        this.year = year;
    }

    public void setMonth(int month) throws InvalidDateException {
        if (month <= 0 || month > 12) {
            throw new InvalidDateException("Invalid month");
        }
        this.month = month;
    }

    public void setDay(int day) throws InvalidDateException {
        if (day <= 0 || day > 31) {
            throw new InvalidDateException("Invalid day");
        }
        this.day = day;
    }
}

public class Main {
    public static void main(String[] args) {
        try {
            MyDate d1 = new MyDate(-1, 13, 32);
        } catch (InvalidDateException e) {
            System.out.println(e.getMessage());
        }

        MyDate d2 = new MyDate();
        try {
            d2.setDay(100);
        } catch (InvalidDateException e) {
            System.out.println(e.getMessage());
        }
    }
}

输出结果为：

Invalid date
Invalid day