Java 得到某一日期的前一天 後一天 並得到該三天分別是星期幾
public static void main(String[] s) throws ParseException{
String day = "2014-08-01";
String beforeWeek = "";
String dayWeek = "";
String afterWeek = "";
String[] weekDatas = {"星期日","星期一","星期二","星期三","星期四","星期五","星期六"};
String beforeDay = ""; //前一天
//根據當前日期得到前一天的日期
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
Date dd = format.parse(day);
Calendar calendar1 = Calendar.getInstance();
calendar1.setTime(dd);
int week_index = calendar1.get(Calendar.DAY_OF_WEEK) - 1;
if(week_index<0){
week_index = 0;
}
dayWeek = weekDatas[week_index];
calendar1.add(Calendar.DATE,-1);
week_index = calendar1.get(Calendar.DAY_OF_WEEK) - 1;
if(week_index<0){
week_index = 0;
}
beforeWeek = weekDatas[week_index];
beforeDay = format.format(calendar1.getTime()) ;
String afterDay = ""; //後一天
//根據當前日期得到後一天的日期
dd = format.parse(day);
Calendar calendar2 = Calendar.getInstance();
calendar2.setTime(dd);
calendar2.add(Calendar.DATE,1);
week_index = calendar2.get(Calendar.DAY_OF_WEEK) - 1;
if(week_index<0){
week_index = 0;
}
afterWeek = weekDatas[week_index];
afterDay = format.format(calendar2.getTime()) ;
System.out.println(beforeDay+beforeWeek);
System.out.println(day+dayWeek);
System.out.println(afterDay+afterWeek);
}