以（yyyy-MM-dd）格式将String转换为java.util.Date，返回类型为Date

Question

I am trying to convert String to java.util.date this way,

My Input string is :"2013-09-18"

import java.text.SimpleDateFormat;
import java.util.Date;

public class DateAndTime {

    public static void main(String[] args) throws Exception {

            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
            Date convertedCurrentDate = sdf.parse("2013-09-18");
            String strDate = new SimpleDateFormat("yyyy-MM-dd").format(convertedCurrentDate);
            System.out.println(strDate);

     }
}

Here convertedCurrentDate is giving output as ""Wed Sep 18 00:00:00 IST 2013"".

Actually I want to get output this way, 2013-09-18 and not ""Wed Sep 18 00:00:00 IST 2013""

So, I tried this way,

String strDate = new SimpleDateFormat("yyyy-MM-dd").format(convertedCurrentDate);
            System.out.println(strDate);

This is giving me output as 2013-09-18.

But the issue is I am getting this '2013-09-18' as string.

What i want is 2013-09-18 with java.util.date datatype and not String

ie,

need to cast strDate to java.util.date.

Can anyone help me in this issue?

Thanks

Answer 1

Reason:
When using println java explicitly calls toString method on that object. When calling toString on Date object it may be using its default date format which leads to above output.

Solution: For just printing purpose do what your doing

String strDate = new SimpleDateFormat("yyyy-MM-dd").format(convertedCurrentDate);  
System.out.println(strDate);

Answer 2

When you invoke System.out.println on a Date object the String representation of that object is printed. This is done by calling method toString() of the corresponding Date object. The String representation of the Date object is predefined by the implementer of that class so you will always get a format like "Wed Sep 18 00:00:00 IST 2013"

You should always invoke the following on the Date object in order to print it in the format you want:

new SimpleDateFormat("yyyy-MM-dd").format(dateObject)

To make your life easier, create a static object of the Date formatter and call it everywhere in your code like:

public static SimpleDateFormat MY_DATE_FORMATTER=  new SimpleDateFormat("yyyy-MM-dd");

And call it like:

System.out.println(MY_DATE_FORMATTER.format(dateObject));

Answer 3

Java不允许Date格式仅是Date部分，每当创建Date对象时，即使日期部分中也没有时间，它也应包含time部分，因此它写为00:00。因此，您不能使用格式化的Date对象，但是可以总是得到格式化的字符串。