java取得當前日期增加一天或多天

代碼如下：

SimpleDateFormat sf = new SimpleDateFormat("yyyy-MM-dd");
Calendar c = Calendar.getInstance();
System.out.println("當前日期:"+sf.format(c.getTime()));
c.add(Calendar.DAY_OF_MONTH, 1);
System.out.println("增加一天后日期:"+sf.format(c.getTime()));
//打印結果
//當前日期：         2013-06-18
//增加一天后日期 ：   2013-06-19

 

Java Calendar獲取年、月、日、時間

 

 Calendar c = Calendar.getInstance(TimeZone.getTimeZone("GMT+08:00"));    //獲取東八區時間

int year = c.get(Calendar.YEAR);    //獲取年   
int month = c.get(Calendar.MONTH) + 1;   //獲取月份，0表示1月份   
int day = c.get(Calendar.DAY_OF_MONTH);    //獲取當前天數   
int first = c.getActualMinimum(c.DAY_OF_MONTH);    //獲取本月最小天數   
int last = c.getActualMaximum(c.DAY_OF_MONTH);    //獲取本月最大天數   
int time = c.get(Calendar.HOUR_OF_DAY);       //獲取當前小時   
int min = c.get(Calendar.MINUTE);          //獲取當前分鍾   
int xx = c.get(Calendar.SECOND);          //獲取當前秒

 

SimpleDateFormat s=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String curDate = s.format(c.getTime());  //當前日期   
System.out.println("當前時間："+year + "-" + month + "-"+ day + " "+time + ":" + min +":" + xx);   
System.out.println("第一天和最后天：" + first +"," + last);
System.out.println("當前日期curDate====：" + curDate);

輸出結果：

當前時間：2012-9-25 22:50:54 第一天和最后天：1,30

當前日期curDate：2012-09-25 22:50:54

 

Calendar的計算

c.add(Calendar.YEAR, 1);   
c.add(Calendar.MONTH, 1);   
c.add(Calendar.DAY_OF_MONTH, 1);  
int year2 = c.get(Calendar.YEAR);   
int month2 = c.get(Calendar.MONTH) + 1;   
int day2 = c.get(Calendar.DAY_OF_MONTH);  
int firstD = c.getActualMinimum(c.DAY_OF_MONTH);   
int lastD = c.getActualMaximum(c.DAY_OF_MONTH);   
System.out.println("當前時間："+year2 + "-" + month2 + "-"+ day2 + " "+time + ":" + min +":" + xx);   
System.out.println("第一天和最后天：" + firstD +"," + lastD);

輸出結果：

當前時間：2013-10-26 23:4:3 第一天和最后天：1,31

 

 

獲取上個月的年、月、日

Calendar c=Calendar.getInstance();
c.add(Calendar.MONTH, -1);//上個月
SimpleDateFormat s=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String year=String.valueOf(c.get(Calendar.YEAR));
String topDay = String.valueOf(c.getActualMinimum(Calendar.DAY_OF_MONTH));
String lastDay = String.valueOf(c.getActualMaximum(Calendar.DAY_OF_MONTH)); 

//上個月
String lastMonth=String.valueOf(c.get(Calendar.MONTH)+1).length()==2?String.valueOf(c.get(Calendar.MONTH)+1):"0"+String.valueOf(c.get(Calendar.MONTH)+1);
String topDayMonth=year+"-"+lastMonth+"-"+"01" + " 00:00:00";
String lastDayMonth = year+"-"+lastMonth+"-"+lastDay+ " 23:59:59";
System.out.println("###year:" + year);
System.out.println("###last month:" + lastMonth);
System.out.println("###topday:" + topDayMonth);
System.out.println("###lastday:" + lastDayMonth);

輸出結果

###year:2013

###last month:04

###topday:2013-04-01 00:00:00

###lastday:2013-04-30 23:59:59

轉自 http://hi.baidu.com/zzm_2007/item/3b967b1cd1586e4e2b3e2258

 

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class DateTest {
    public static Date geLastWeekMonday(Date date) {
        Calendar cal = Calendar.getInstance();
        cal.setTime(getThisWeekMonday(date));
        cal.add(Calendar.DATE, -7);
        return cal.getTime();
    }

    public static Date getThisWeekMonday(Date date) {
        Calendar cal = Calendar.getInstance();
        cal.setTime(date);
        // 獲得當前日期是一個星期的第幾天
        int dayWeek = cal.get(Calendar.DAY_OF_WEEK);
        if (1 == dayWeek) {
            cal.add(Calendar.DAY_OF_MONTH, -1);
        }
        // 設置一個星期的第一天，按中國的習慣一個星期的第一天是星期一
        cal.setFirstDayOfWeek(Calendar.MONDAY);
        // 獲得當前日期是一個星期的第幾天
        int day = cal.get(Calendar.DAY_OF_WEEK);
        // 根據日歷的規則，給當前日期減去星期幾與一個星期第一天的差值
        cal.add(Calendar.DATE, cal.getFirstDayOfWeek() - day);
        return cal.getTime();
    }

    public static Date getNextWeekMonday(Date date) {
        Calendar cal = Calendar.getInstance();
        cal.setTime(getThisWeekMonday(date));
        cal.add(Calendar.DATE, 7);
        return cal.getTime();
    }

    public static void main(String[] args) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        try {
            Date date = sdf.parse("2017-09-10");
            System.out.println("今天是" + sdf.format(date));
            System.out.println("上周一" + sdf.format(geLastWeekMonday(date)));
            System.out.println("本周一" + sdf.format(getThisWeekMonday(date)));
            System.out.println("下周一" + sdf.format(getNextWeekMonday(date)));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

輸出結果：

今天是2017-09-10
上周一2017-08-28
本周一2017-09-04
下周一2017-09-11