如何在安卓中比较日期时间

Question

我有日期，date1（now）和date2，它们以JSON字符串返回，说2016-07-09 21:26:04。

我想比较这两个日期，如下所示

if(date1 < date2){
}

Answer 1

以下是在 Android 中比较两个 DateTime 对象的代码：

 public void onDateSelected(DateTime dateSelected) {
    DateTime currentDateTime = new DateTime(); 
    try{
        // You can use any format to compare by spliting the dateTime 
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZZZZZ");
        String str1 = dateSelected.toString();
        Date selectedDate = formatter.parse(str1);
        String str2 = currentDateTime.toString();
        Date currentDate = formatter.parse(str2);
        if (selectedDate.compareTo(currentDate)<0)
        {
            System.out.println("current date is Greater than my selected date");
        }
        else
        {
            System.out.println("selected date is Greater than my current date"); 
        }
    }catch (ParseException e1){
        e1.printStackTrace();
    }
 }

Answer 2

我会这样做：

1. 解析 in to Date 对象
2. 比较那些

例：

 public static void main(String x[]) throws ParseException {
    String s1 = "2016-07-09 21:26:04";
    String s2 = "2006-07-09 21:26:04";
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    Date d1 = sdf.parse(s1);
    Date d2 = sdf.parse(s2);
    int compareResult = d1.compareTo(d2);
    if (compareResult > 0) {
        System.out.println(s1 + " is younger than " + s2);
    } else if (compareResult < 0) {
        System.out.println(s1 + " is younger than " + s2);
    } else {
        System.out.println(s1 + " is equals than " + s2);
    }
    }

Answer 3

SimpleDateFormat sdf =  new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
Date today= new Date();
try {
        if (today.before(sdf.forrmat(json_string_date))) {
          // If start date is before end date.
          // Do your piece of code
         } 
    }catch (ParseException e) {
        e.printStackTrace();
    }