want current date and time in “dd/MM/yyyy HH:mm:ss.SS” format

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南旧
南旧 2020-11-22 01:31

I am using following code to get date in \"dd/MM/yyyy HH:mm:ss.SS\" format.

    import java.text.SimpleDateFormat;
    import java.util.Calendar;
    import          


        
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  • 2020-11-22 02:21

    You can't - because you're calling Date.toString() which will always include the system time zone if that's in the default date format for the default locale. The Date value itself has no concept of a format. If you want to format it in a particular way, use SimpleDateFormat.format()... using Date.toString() is almost always a bad idea.

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  • 2020-11-22 02:21

    Here's a simple snippet working in Java 8 and using the "new" date and time API LocalDateTime:

    DateTimeFormatter dtf = DateTimeFormatter.ofPattern("dd/MM/yyyy HH:mm:ss.SS");
    LocalDateTime now = LocalDateTime.now();
    System.out.println(dtf.format(now)); 
    
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  • 2020-11-22 02:23

    Disclaimer: this answer does not endorse the use of the Date class (in fact it’s long outdated and poorly designed, so I’d rather discourage it completely). I try to answer a regularly recurring question about date and time objects with a format. For this purpose I am using the Date class as example. Other classes are treated at the end.

    You don’t want to

    You don’t want a Date with a specific format. Good practice in all but the simplest throw-away programs is to keep your user interface apart from your model and your business logic. The value of the Date object belongs in your model, so keep your Date there and never let the user see it directly. When you adhere to this, it will never matter which format the Date has got. Whenever the user should see the date, format it into a String and show the string to the user. Similarly if you need a specific format for persistence or exchange with another system, format the Date into a string for that purpose. If the user needs to enter a date and/or time, either accept a string or use a date picker or time picker.

    Special case: storing into an SQL database. It may appear that your database requires a specific format. Not so. Use yourPreparedStatement.setObject(yourParamIndex, yourDateOrTimeObject) where yourDateOrTimeObject is a LocalDate, Instant, LocalDateTime or an instance of an appropriate date-time class from java.time. And again don’t worry about the format of that object. Search for more details.

    You cannot

    A Date hasn’t got, as in cannot have a format. It’s a point in time, nothing more, nothing less. A container of a value. In your code sdf1.parse converts your string into a Date object, that is, into a point in time. It doesn’t keep the string nor the format that was in the string.

    To finish the story, let’s look at the next line from your code too:

        System.out.println("Current date in Date Format: "+date);
    

    In order to perform the string concatenation required by the + sign Java needs to convert your Date into a String first. It does this by calling the toString method of your Date object. Date.toString always produces a string like Thu Jan 05 21:10:17 IST 2012. There is no way you could change that (except in a subclass of Date, but you don’t want that). Then the generated string is concatenated with the string literal to produce the string printed by System.out.println.

    In short “format” applies only to the string representations of dates, not to the dates themselves.

    Isn’t it strange that a Date hasn’t got a format?

    I think what I’ve written is quite as we should expect. It’s similar to other types. Think of an int. The same int may be formatted into strings like 53,551, 53.551 (with a dot as thousands separator), 00053551, +53 551 or even 0x0000_D12F. All of this formatting produces strings, while the int just stays the same and doesn’t change its format. With a Date object it’s exactly the same: you can format it into many different strings, but the Date itself always stays the same.

    Can I then have a LocalDate, a ZonedDateTime, a Calendar, a GregorianCalendar, an XMLGregorianCalendar, a java.sql.Date, Time or Timestamp in the format of my choice?

    No, you cannot, and for the same reasons as above. None of the mentioned classes, in fact no date or time class I have ever met, can have a format. You can have your desired format only in a String outside your date-time object.

    Links

    • Model–view–controller on Wikipedia
    • All about java.util.Date on Jon Skeet’s coding blog
    • Answers by Basil Bourque and Pitto explaining what to do instead (also using classes that are more modern and far more programmer friendly than Date)
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  • 2020-11-22 02:29

    use

    Date date = new Date();
    String strDate = sdf.format(date);
    

    intead Of

    Calendar cal = Calendar.getInstance();
    String strDate = sdf.format(cal.getTime());
    
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