Java 编写一个简单日历 2020-07-25

//1.键盘录入提示信息:

Scanner sc =new Scanner( System.in );

System.out.print("请输入你想要查看的日期：请按照：(2020-7-12)的格式进行输入：" );

String strDate = sc.next();

System.out.println( strDate+"的日历：" );

//2.将上面接受的String-->Calendar:

//2.1:String-->Date;

java.sql.Date d = java.sql.Date.valueOf( strDate );

//2.2Date--->Calendar:

Calendar cal = Calendar.getInstance();

cal.setTime( d );

//3.输出日历的星期几一到星期日:

System.out.println("日\t一\t二\t三\t四\t五\t六\t" );

//4。遍历一到本月最大天的天数:

//4.1:先求出本月的最大天数：

int maxDate = cal.getActualMaximum( Calendar.DATE );

//8.求出当天日期:

int nowDate = cal.get( Calendar.DATE );

//9.求出本月的第一天是这周中的星期几：

//9.1将日期置成本月的第一天：

cal.set( Calendar.DATE,1 );

int dayOfWeek = cal.get( Calendar.DAY_OF_WEEK );

//10.求出一号前面的空格数：

int space = dayOfWeek -1;

//6.引用一个计数器，用来计算换行:每7个就换行:

int count  =  space;

//11.遍历space:

for (int a =1;a <= space;a++){

System.out.print("\t");

}

//5:遍历本月的最大天数：

for (int a =1; a <= maxDate; a++) {

//7.在当天日期上加上一个*号

    if (a == nowDate){

System.out.print(a+"*\t");

    }else{

System.out.print(a+"\t");

    }

count++;

    if (count %7 ==0){

System.out.println();

    }

}