代码如下：
SimpleDateFormat sf = new SimpleDateFormat("yyyy-MM-dd");
Calendar c = Calendar.getInstance();
System.out.println("当前日期:"+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()));
//打印结果
//当前日期： 2013-06-18
//增加一天后日期 ： 2013-06-19
Java Calendar获取年、月、日、时间
Calendar c = Calendar.getInstance(TimeZone.getTimeZone("GMT+08:00")); //获取东八区时间
int year = c.get(Calendar.YEAR); //获取年
int month = c.get(Calendar.MONTH) + 1; //获取月份，0表示1月份
int day = c.get(Calendar.DAY_OF_MONTH); //获取当前天数
int first = c.getActualMinimum(c.DAY_OF_MONTH); //获取本月最小天数
int last = c.getActualMaximum(c.DAY_OF_MONTH); //获取本月最大天数
int time = c.get(Calendar.HOUR_OF_DAY); //获取当前小时
int min = c.get(Calendar.MINUTE); //获取当前分钟
int xx = c.get(Calendar.SECOND); //获取当前秒
SimpleDateFormat s=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String curDate = s.format(c.getTime()); //当前日期
System.out.println("当前时间："+year + "-" + month + "-"+ day + " "+time + ":" + min +":" + xx);
System.out.println("第一天和最后天：" + first +"," + last);
System.out.println("当前日期curDate====：" + curDate);
输出结果：
当前时间：2012-9-25 22:50:54 第一天和最后天：1,30
当前日期curDate：2012-09-25 22:50:54
Calendar的计算
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("当前时间："+year2 + "-" + month2 + "-"+ day2 + " "+time + ":" + min +":" + xx);
System.out.println("第一天和最后天：" + firstD +"," + lastD);
输出结果：
当前时间：2013-10-26 23:4:3 第一天和最后天：1,31
获取上个月的年、月、日
Calendar c=Calendar.getInstance();
c.add(Calendar.MONTH, -1);//上个月
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)); //上个月
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);
输出结果
###year:2013
###last month:04
###topday:2013-04-01 00:00:00
###lastday:2013-04-30 23:59:59
转自 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);
// 获得当前日期是一个星期的第几天
int dayWeek = cal.get(Calendar.DAY_OF_WEEK);
if (1 == dayWeek) {
cal.add(Calendar.DAY_OF_MONTH, -1);
}
// 设置一个星期的第一天，按中国的习惯一个星期的第一天是星期一
cal.setFirstDayOfWeek(Calendar.MONDAY);
// 获得当前日期是一个星期的第几天
int day = cal.get(Calendar.DAY_OF_WEEK);
// 根据日历的规则，给当前日期减去星期几与一个星期第一天的差值
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();
}
}
}
输出结果：
今天是2017-09-10
上周一2017-08-28
本周一2017-09-04
下周一2017-09-11