Calander 的小程序 簡單日曆的製作

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直接上乾貨 代碼
這裏把 主函數上傳上去了 因爲聲明異常了 所以不省略了

  public static void main(String[] args) throws ParseException {//這裏偷懶 直接異常聲明
        Scanner scanner = new Scanner(System.in);
        System.out.println("請輸入你要查詢的日期:");
        String  dateStr =scanner.next();
        SimpleDateFormat sim = new SimpleDateFormat("yyyy-MM-dd");
        Date data =  sim.parse(dateStr);
        Calendar calendar = new GregorianCalendar(); //實例化一個標準日曆
        calendar.setTime(data); //將時間賦值給calendar
        int day = calendar.get(Calendar.DAY_OF_MONTH);
        calendar.set(Calendar.DAY_OF_MONTH,1); //用來賦值當前日期這個月的第幾天
          //DAY_OF_MONTH 當前日期 是這個月的第幾天
         //Calendar.DAY_OF_YEAR 當前日期是這一年的第幾天
        //DAY_OF_WEEK，用來獲得當前日期是一週的第幾天
        System.out.println("日\t一\t二\t三\t四\t五\t六");
        for (int i = 0; i <calendar.get(Calendar.DAY_OF_WEEK)-1; i  ) {
            System.out.print("\t");
        }
        int days = calendar.getActualMaximum(Calendar.DATE); //獲取當前月的最大天數
        for (int i = 1; i <=days; i  ) {
             int nowDay = calendar.get(Calendar.DAY_OF_MONTH);
            if(day == nowDay ){ //如果循環日期 等於輸入日期 *號標出
                System.out.print(calendar.get(Calendar.DAY_OF_MONTH) "*" "\t");
            }else {//否則正常輸出 
                System.out.print(calendar.get(Calendar.DAY_OF_MONTH)   "\t");
            }
            if(calendar.get(Calendar.DAY_OF_WEEK)==Calendar.SATURDAY){ //如果是週六換行
                System.out.println();
            }
            calendar.add(Calendar.DAY_OF_MONTH,1); //每次 1
        }
    }

運行結果如下：

下面 大家來溫故下 Calander 的知識

獲取時間

import java.text.SimpleDateFormat;
import java.util.Calendar;
public class CalenderTest {
	//獲取時間：以目前系統時間 ：2019:01:27 16:27:27 爲例
	@Test
	public void testGetCalender() {
		Calendar cal = Calendar.getInstance();    							//Calendar類的實例化
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");	//時間的格式化

		//當前系統時間
		Date date = cal.getTime();								//date=Sun Jan 27 16:27:27 CST 2019
		String nowTime = sdf.format(cal.getTime());				//nowTime=2019-01-27 16:27:27

		//當前年     
		int year = cal.get(Calendar.YEAR);						//year=2019

		//當前月 Calendar.MONTH從0開始 ,使用時通常會 1  
		int month = cal.get(Calendar.MONTH)   1;				//month=1

		//當前日：兩種方法等價
		int day_of_month = cal.get(Calendar.DAY_OF_MONTH);		//day_of_month=27   
		int day = cal.get(Calendar.DATE);  						//day=27

		//獲取當月day的最大值！！
		int max_day_of_month = cal.getActualMaximum(Calendar.DAY_OF_MONTH);	//max_day_of_month=31

		//當前時鐘：24小時制
		int hour24 = cal.get(Calendar.HOUR_OF_DAY);				//hour24=16

		//當前時鐘：12小時制     
		int hour12 = cal.get(Calendar.HOUR); 					//hour12=4

		//當前:分鐘     
		int minute = cal.get(Calendar.MINUTE);   				//minute=27

		//當前秒     
		int second = cal.get(Calendar.SECOND);  				//second=27

		//星期幾：用數字（1~7）表示（星期日~星期六），使用時通常會-1
		int day_of_week = cal.get(Calendar.DAY_OF_WEEK) - 1;	//day_of_week=0

		//上午-0；下午-1     
		int amOrPm = cal.get(Calendar.AM_PM);  					//amOrPm=1

		//當前年的第幾周
		int week_of_year = cal.get(Calendar.WEEK_OF_YEAR);		//week_of_year=5

		//當前月的星期數
		int week_of_month = cal.get(Calendar.WEEK_OF_MONTH);	//week_of_month=5

		//當前月中的第幾個星期     
		int day_of_week_in_month = cal.get(Calendar.DAY_OF_WEEK_IN_MONTH); //day_of_week_in_month=4

		//當前年的第幾天     
		int day_of_year = cal.get(Calendar.DAY_OF_YEAR);		//day_of_year=27
	}
}

設置時間

import java.text.SimpleDateFormat;
import java.util.Calendar;
public class CalenderTest {
	//設置時間：以目前系統時間 ：2019:01:27 16:27:27 爲例
	@Test
	public void testSetCalender() {
		Calendar cal = Calendar.getInstance();    							//Calendar類的實例化
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");	//時間的格式化

		//1.當前系統時間
		Date date = cal.getTime();							//data=Sun Jan 27 16:27:27 CST 2019
		String nowTime = sdf.format(cal.getTime());			//nowTime=2019-01-27 16:27:27

		//2.設置時間：不設置項，默認Calendar已經存在日期
		cal.set(Calendar.HOUR_OF_DAY, 11);
		cal.set(Calendar.MINUTE, 30);
		cal.set(Calendar.SECOND, 30);
		String date1 = sdf.format(cal.getTime());			//time=2019-01-27 11:30:30

		//3.設置時間：全部設置，則輸出自定義時間
		cal.set(Calendar.YEAR, 2018);
		cal.set(Calendar.MARCH, 7);
		cal.set(Calendar.DATE, 21);
		String date2 = sdf.format(cal.getTime());			//time=2018-08-21 11:30:30

		//4.時間重置：Date date = new date();
		String newDate1 = sdf.format(cal.getTime());		//newDate1=2018-08-21 11:30:30
		String newDate2 = sdf.format(new Date());			//newDate2=2019:01:27 16:27:27
	}
}

時間運算

import java.text.SimpleDateFormat;
import java.util.Calendar;
public class CalenderTest {
	//時間運算：以目前系統時間 ：2019:01:27 16:27:27 爲例
	@Test
	public void testAddCalender() {
		Calendar cal = Calendar.getInstance();    							//Calendar類的實例化
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");	//時間的格式化
		
		String nowTime = sdf.format(cal.getTime());		//nowTime=2019-01-27 16:27:27
		
		cal.add(Calendar.YEAR, 1);					
		String time1 = sdf.format(cal.getTime());		//年:2020-01-27 16:27:27

		cal.add(Calendar.MONTH, 2);					
		String time2 = sdf.format(cal.getTime());		//月:2020-03-27 16:27:27

		cal.add(Calendar.DATE, 5);					
		String time3 = sdf.format(cal.getTime());		//日:2020-04-01 16:27:27

		cal.add(Calendar.HOUR_OF_DAY, -1);			
		String time4 = sdf.format(cal.getTime());		//時:2020-04-01 15:27:27

		cal.add(Calendar.MINUTE, 1);				
		String time5 = sdf.format(cal.getTime());		//分:2020-04-01 15:28:27

		cal.add(Calendar.SECOND, 1);				
		String time6 = sdf.format(cal.getTime());		//秒:2020-04-01 15:27:28
	}
}

上述總結的操作時間方法 不是自己敲得 轉載於 點它
有問題評論區見 大家一起探討呀 ！！！