日期格式转化

时间格式转化和转为英文， 以及日期序数化。

public class DateParse {
@SuppressWarnings("unused")
//根据教师类型存储英文日期
public static String ParseDate(String time, String teacherType)
throws ParseException {

if (null == time && "" == time) {
return "";
}
Locale l = new Locale("en");
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Date date = sdf.parse(time);
String day = String.format("%td", date);
String month = String.format(l, "%tB", date);
String year = String.format("%tY", date);
day = getOrdinal(day);
//5001 特邀 5002 特聘
/*if (teacherType == "5001") {
return month + " " + day + "," + year;*/
/*} else {*/
return month + " ," + year;
/*}*/
}

//日期转化为序数词
public static String getOrdinal(String day) {

int dayNum = Integer.parseInt(day);
String tail = null;
if (1 == dayNum) {
return "1st";
} else if (2 == dayNum) {
return "2nd";
} else if (3 == dayNum) {
return "3rd";
} else if (dayNum >= 20) {
int last = dayNum % 10;
if (1 == last) {
tail = "st";
} else if (2 == last) {
tail = "nd";
} else if (3 == last) {
tail = "rd";
} else {
tail = "th";
}
} else {
tail = "th";
}
return dayNum + tail;
}

//日期转化，去0
public static String DateChange(String time) throws ParseException {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-M-d");
Date date = sdf.parse(time);

String resultTime = sdf.format(date);

return resultTime;

}
//讲师聘用开始结束时间格式存入
public static String DateChangeEn(String time) throws ParseException {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Date date = sdf.parse(time);

String resultTime = sdf.format(date);

return resultTime;

}

}