simpleDateFormat time conversion all tricks

1. Basic see blog https://blog.csdn.net/hanchaob323/article/details/7371731

2. Convert it yourself

//解析时间
private String dateToString(String dateStr){
    SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
    String strDate = null;
    try {
        strDate = formatter.parse(dateStr).toString();
    } catch (ParseException e) { e.printStackTrace(); }
    return strDate;
}