import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
/**
* @author Gerrard
*/
public class TestGetWeek {
public static void main(String[] args) {
int currentMaxDays = getCurrentMonthDay();
int maxDaysByDate = getDaysByYearMonth(2012, 11);
String week = getDayOfWeekByDate("2012-12-25");
System.out.println("本月天数：" + currentMaxDays);
System.out.println("2012年11月天数：" + maxDaysByDate);
System.out.println("2012-12-25是：" + week);
}
/**
* 获取当月的 天数
* */
public static int getCurrentMonthDay() {
Calendar a = Calendar.getInstance();
a.set(Calendar.DATE, 1);
a.roll(Calendar.DATE, -1);
int maxDate = a.get(Calendar.DATE);
return maxDate;
}
/**
* 根据年 月 获取对应的月份 天数
* */
public static int getDaysByYearMonth(int year, int month) {
Calendar a = Calendar.getInstance();
a.set(Calendar.YEAR, year);
a.set(Calendar.MONTH, month - 1);
a.set(Calendar.DATE, 1);
a.roll(Calendar.DATE, -1);
int maxDate = a.get(Calendar.DATE);
return maxDate;
}
/**
* 根据日期获取对应的日 * */
public static int getCurrentDateToDay(String currentDate){
DateFormat df = new SimpleDateFormat("yyyy-MM-dd");
Calendar cal = Calendar.getInstance();
try {
cal.setTime(df.parse(currentDate));
} catch (ParseException e) {
e.printStackTrace();
}
return cal.get(Calendar.DATE);
}
/**
* 根据日期 找到对应日期的 星期
*/
public static String getDayOfWeekByDate(String date) {
String dayOfweek = "-1";
try {
SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
Date myDate = myFormatter.parse(date);
SimpleDateFormat formatter = new SimpleDateFormat("E");
String str = formatter.format(myDate);
dayOfweek = str;
} catch (Exception e) {
System.out.println("错误!");
}
return dayOfweek;
}
}
获取3天前的日期
//获取开始时间 - 过车数据只查询3天的过车数据
import java.util.Calendar;
Calendar c = Calendar.getInstance();
c.add(Calendar.DATE, -2);
String passUpTime = c.get(Calendar.YEAR) + "-" + (c.get(Calendar.MONTH) + 1) + "-" + c.get(Calendar.DATE) + "@00:00:00";