1国葬、偷懶直接貼代碼轮锥，方便下次使用：
/**
* .Description://根據(jù)字符日期返回星期幾
* .Author:麥克勞林
* .@Date: 2018/12/29
*/
public String getWeek(String dateTime){
String week = "";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
try {
Date date = sdf.parse(dateTime);
SimpleDateFormat dateFm = new SimpleDateFormat("EEEE");
week = dateFm.format(date);
week=week.replaceAll("星期","周");
}catch (ParseException e){
e.printStackTrace();
}
return week;
}
/**
* 獲取過去7天內(nèi)的日期數(shù)組
* @param intervals intervals天內(nèi)
* @return 日期數(shù)組
*/
public ArrayList<String> getDays(int intervals) {
ArrayList<String> pastDaysList = new ArrayList<>();
for (int i = intervals -1; i >= 0; i--) {
pastDaysList.add(getPastDate(i));
}
return pastDaysList;
}
/**
* 獲取過去第幾天的日期
* @param past
* @return
*/
public String getPastDate(int past) {
Calendar calendar = Calendar.getInstance();
calendar.set(Calendar.DAY_OF_YEAR, calendar.get(Calendar.DAY_OF_YEAR) - past);
Date today = calendar.getTime();
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
String result = format.format(today);
return result;
}
2、SQL根據(jù)日期查詢某天數(shù)據(jù)
<!--查詢某一天數(shù)據(jù) -->
select * from table_name where date_format(create_date,'%Y-%m-%d') = '2018-12-29';
<!-- 查詢某一月數(shù)據(jù)-->
select *from table_name where year(create_date) = '2018' and month(create_date) = '12';
