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Change date format in a Java string

I've a String representing a date.

String date_s = "2011-01-18 00:00:00.0";

I'd like to convert it to a Date and output it in YYYY-MM-DD format.

2011-01-18

How can I achieve this?

Okay, based on the answers I retrieved below, here's something I've tried:

String date_s = " 2011-01-18 00:00:00.0"; 
SimpleDateFormat dt = new SimpleDateFormat("yyyyy-mm-dd hh:mm:ss"); 
Date date = dt.parse(date_s); 
SimpleDateFormat dt1 = new SimpleDateFormat("yyyyy-mm-dd");
System.out.println(dt1.format(date));

But it outputs 02011-00-1 instead of the desired 2011-01-18. What am I doing wrong?

yyyyy is not the same as yyyy. :)
A boomerang question. What is your use case? Because it is possible that you should use built-in patterns (DateFormat.getDateTimeInstance()).
The month is represented with MM in the format string, not with mm like in the examples above. mm means minutes.
I changed yyyy-mm-dd to yyyy-MM-dd, cause initial version didn't work
"mm" is number of minutes :)

C
Community

Use LocalDateTime#parse() (or ZonedDateTime#parse() if the string happens to contain a time zone part) to parse a String in a certain pattern into a LocalDateTime.

String oldstring = "2011-01-18 00:00:00.0";
LocalDateTime datetime = LocalDateTime.parse(oldstring, DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.S"));

Use LocalDateTime#format() (or ZonedDateTime#format()) to format a LocalDateTime into a String in a certain pattern.

String newstring = datetime.format(DateTimeFormatter.ofPattern("yyyy-MM-dd"));
System.out.println(newstring); // 2011-01-18

Or, when you're not on Java 8 yet, use SimpleDateFormat#parse() to parse a String in a certain pattern into a Date.

String oldstring = "2011-01-18 00:00:00.0";
Date date = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.S").parse(oldstring);

Use SimpleDateFormat#format() to format a Date into a String in a certain pattern.

String newstring = new SimpleDateFormat("yyyy-MM-dd").format(date);
System.out.println(newstring); // 2011-01-18

See also:

Java string to date conversion

Update: as per your failed attempt: the patterns are case sensitive. Read the java.text.SimpleDateFormat javadoc what the individual parts stands for. So stands for example M for months and m for minutes. Also, years exist of four digits yyyy, not five yyyyy. Look closer at the code snippets I posted here above.


What if you want the date to look like "Monday 1st September 2012"?
@crm: Just click the javadoc link, figure the necessary pattern characters there and alter the pattern accordingly.
When you're not on Java 8 yet, consider using the backport, ThreeTen Backport, and then the first examples from the answer. Or for Android below API level 26, ThreeTenABP.
D
Dev

Formatting are CASE-SENSITIVE so USE MM for month not mm (this is for minute) and yyyy For Reference you can use following cheatsheet.

G   Era designator  Text    AD
y   Year    Year    1996; 96
Y   Week year   Year    2009; 09
M   Month in year   Month   July; Jul; 07
w   Week in year    Number  27
W   Week in month   Number  2
D   Day in year Number  189
d   Day in month    Number  10
F   Day of week in month    Number  2
E   Day name in week    Text    Tuesday; Tue
u   Day number of week (1 = Monday, ..., 7 = Sunday)    Number  1
a   Am/pm marker    Text    PM
H   Hour in day (0-23)  Number  0
k   Hour in day (1-24)  Number  24
K   Hour in am/pm (0-11)    Number  0
h   Hour in am/pm (1-12)    Number  12
m   Minute in hour  Number  30
s   Second in minute    Number  55
S   Millisecond Number  978
z   Time zone   General time zone   Pacific Standard Time; PST; GMT-08:00
Z   Time zone   RFC 822 time zone   -0800
X   Time zone   ISO 8601 time zone  -08; -0800; -08:00

Examples:

"yyyy.MM.dd G 'at' HH:mm:ss z"  2001.07.04 AD at 12:08:56 PDT
"EEE, MMM d, ''yy"  Wed, Jul 4, '01
"h:mm a"    12:08 PM
"hh 'o''clock' a, zzzz" 12 o'clock PM, Pacific Daylight Time
"K:mm a, z" 0:08 PM, PDT
"yyyyy.MMMMM.dd GGG hh:mm aaa"  02001.July.04 AD 12:08 PM
"EEE, d MMM yyyy HH:mm:ss Z"    Wed, 4 Jul 2001 12:08:56 -0700
"yyMMddHHmmssZ" 010704120856-0700
"yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"   2001-07-04T12:08:56.235-0700
"yyyy-MM-dd'T'HH:mm:ss.SSSXXX"   2001-07-04T12:08:56.235-07:00
"YYYY-'W'ww-u"  2001-W27-3

"yyyy-MM-dd'T'HH:mm:ss.SSSZ" should be "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"
no if u put Z in single quote it will give Z as output but without it it will give Timezone. eg. 2014-08-14T01:24:57.236Z and from without it 2014-08-14T01:24:57.236-0530 --> I tried on jdk1.7
"yyyyy.MMMMM.dd GGG hh:mm aaa" 02001.July.04 AD 12:08 PM Note extra M in month. Four not five!
if it's 4 letters or more, then the full form is used. so you can use 4 times m or even 5 times m its same
This is pretty much a Copy-Paste of the docs. No extra explanations are being provided, and there is no link to the docs where more info could be acquired if needed. -1. (Here's the link btw)
H
Hovercraft Full Of Eels

The answer is of course to create a SimpleDateFormat object and use it to parse Strings to Date and to format Dates to Strings. If you've tried SimpleDateFormat and it didn't work, then please show your code and any errors you may receive.

Addendum: "mm" in the format String is not the same as "MM". Use MM for months and mm for minutes. Also, yyyyy is not the same as yyyy. e.g.,:

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

public class FormateDate {

    public static void main(String[] args) throws ParseException {
        String date_s = "2011-01-18 00:00:00.0";

        // *** note that it's "yyyy-MM-dd hh:mm:ss" not "yyyy-mm-dd hh:mm:ss"  
        SimpleDateFormat dt = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
        Date date = dt.parse(date_s);

        // *** same for the format String below
        SimpleDateFormat dt1 = new SimpleDateFormat("yyyy-MM-dd");
        System.out.println(dt1.format(date));
    }

}

import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; public class formateDate { /** * @param args * @throws ParseException */ public static void main(String[] args) throws ParseException { // TODO Auto-generated method stub String date_s=" 2011-01-18 00:00:00.0"; SimpleDateFormat dt= new SimpleDateFormat("yyyyy-mm-dd hh:mm:ss"); Date date=dt.parse(date_s); SimpleDateFormat dt1= new SimpleDateFormat("yyyyy-mm-dd"); System.out.println( dt1.format(date)); } } i want out put should be "2011-01-18" but out put is 02011-00-1
Post any code you have as an addition to the original question (indented four spaces). This way it will retain its formatting and we can then read it.
See edit to my answer above. You're using "mm" in your format String where you should be using "MM"
hh will give you the hour in the range 1-12, you'll need to use a in addition to print/parse AM or PM. To print/parse the hour in the range 0-23, use HH.
M
M--

Why not simply use this

Date convertToDate(String receivedDate) throws ParseException{
        SimpleDateFormat formatter = new SimpleDateFormat("dd-MM-yyyy");
        Date date = formatter.parse(receivedDate);
        return date;
    }

Also, this is the other way :

DateFormat df = new SimpleDateFormat("dd/MM/yyyy");
String requiredDate = df.format(new Date()).toString();

or

Date requiredDate = df.format(new Date());

Why not use this? Because (a) it ignores the issue of time zone. Determining the date depends on the time zone. This code depends on the JVM's default time zone. So, results may vary inadvertently. And (b) because the java.util.Date and SimpleDateFormat classes are notoriously troublesome and should be avoided.
always return strin, Date requiredDate = df.format(new Date());
V
Vitalii Fedorenko

Using the java.time package in Java 8 and later:

String date = "2011-01-18 00:00:00.0";
TemporalAccessor temporal = DateTimeFormatter
    .ofPattern("yyyy-MM-dd HH:mm:ss.S")
    .parse(date); // use parse(date, LocalDateTime::from) to get LocalDateTime
String output = DateTimeFormatter.ofPattern("yyyy-MM-dd").format(temporal);

B
Bryan

[edited to include BalusC's corrections] The SimpleDateFormat class should do the trick:

String pattern = "yyyy-MM-dd HH:mm:ss.S";
SimpleDateFormat format = new SimpleDateFormat(pattern);
try {
  Date date = format.parse("2011-01-18 00:00:00.0");
  System.out.println(date);
} catch (ParseException e) {
  e.printStackTrace();
}

DD stands for "day in year", not "day in month". hh stands for "hour in am/pm (1-12)", not "hour in day (0-23)".
T
Touchstone

Please refer "Date and Time Patterns" here. http://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html

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

public class DateConversionExample{

  public static void main(String arg[]){

    try{

    SimpleDateFormat sourceDateFormat = new SimpleDateFormat("yyyy-MM-DD HH:mm:ss");

    Date date = sourceDateFormat.parse("2011-01-18 00:00:00.0");


    SimpleDateFormat targetDateFormat = new SimpleDateFormat("yyyy-MM-dd");
    System.out.println(targetDateFormat.format(date));

    }catch(ParseException e){
        e.printStackTrace();
    }
  } 

}

B
Basil Bourque

Other answers are correct, basically you had the wrong number of "y" characters in your pattern.

Time Zone

One more problem though… You did not address time zones. If you intended UTC, then you should have said so. If not, the answers are not complete. If all you want is the date portion without the time, then no issue. But if you do further work that may involve time, then you should be specifying a time zone.

Joda-Time

Here is the same kind of code but using the third-party open-source Joda-Time 2.3 library

// © 2013 Basil Bourque. This source code may be used freely forever by anyone taking full responsibility for doing so.

String date_s = "2011-01-18 00:00:00.0";

org.joda.time.format.DateTimeFormatter formatter = org.joda.time.format.DateTimeFormat.forPattern( "yyyy-MM-dd' 'HH:mm:ss.SSS" );
// By the way, if your date-time string conformed strictly to ISO 8601 including a 'T' rather than a SPACE ' ', you could
// use a formatter built into Joda-Time rather than specify your own: ISODateTimeFormat.dateHourMinuteSecondFraction().
// Like this:
//org.joda.time.DateTime dateTimeInUTC = org.joda.time.format.ISODateTimeFormat.dateHourMinuteSecondFraction().withZoneUTC().parseDateTime( date_s );

// Assuming the date-time string was meant to be in UTC (no time zone offset).
org.joda.time.DateTime dateTimeInUTC = formatter.withZoneUTC().parseDateTime( date_s );
System.out.println( "dateTimeInUTC: " + dateTimeInUTC );
System.out.println( "dateTimeInUTC (date only): " + org.joda.time.format.ISODateTimeFormat.date().print( dateTimeInUTC ) );
System.out.println( "" ); // blank line.

// Assuming the date-time string was meant to be in Kolkata time zone (formerly known as Calcutta). Offset is +5:30 from UTC (note the half-hour).
org.joda.time.DateTimeZone kolkataTimeZone = org.joda.time.DateTimeZone.forID( "Asia/Kolkata" );
org.joda.time.DateTime dateTimeInKolkata = formatter.withZone( kolkataTimeZone ).parseDateTime( date_s );
System.out.println( "dateTimeInKolkata: " + dateTimeInKolkata );
System.out.println( "dateTimeInKolkata (date only): " + org.joda.time.format.ISODateTimeFormat.date().print( dateTimeInKolkata ) );
// This date-time in Kolkata is a different point in the time line of the Universe than the dateTimeInUTC instance created above. The date is even different.
System.out.println( "dateTimeInKolkata adjusted to UTC: " + dateTimeInKolkata.toDateTime( org.joda.time.DateTimeZone.UTC ) );

When run…

dateTimeInUTC: 2011-01-18T00:00:00.000Z
dateTimeInUTC (date only): 2011-01-18

dateTimeInKolkata: 2011-01-18T00:00:00.000+05:30
dateTimeInKolkata (date only): 2011-01-18
dateTimeInKolkata adjusted to UTC: 2011-01-17T18:30:00.000Z

F
Fathah Rehman P
try
 {
    String date_s = "2011-01-18 00:00:00.0";
    SimpleDateFormat simpledateformat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.S");
    Date tempDate=simpledateformat.parse(date_s);
    SimpleDateFormat outputDateFormat = new SimpleDateFormat("yyyy-MM-dd");           
    System.out.println("Output date is = "+outputDateFormat.format(tempDate));
  } catch (ParseException ex) 
  {
        System.out.println("Parse Exception");
  }

c
cнŝdk

You can just use:

Date yourDate = new Date();

SimpleDateFormat DATE_FORMAT = new SimpleDateFormat("yyyy-MM-dd");
String date = DATE_FORMAT.format(yourDate);

It works perfectly!


this code returns error "Uncaught SyntaxError: Unexpected identifier"
@IvanFrolov may be you have a missing import, in which line you get the error?
oh, sorry - did not noticed that it's solution for Java, I've searched solution for javascript))) (btw - already found). Thanks!
Ah okay, it's obvious now.
R
Ralph
public class SystemDateTest {

    String stringDate;

    public static void main(String[] args) {
        SystemDateTest systemDateTest = new SystemDateTest();
        // format date into String
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("dd-MM-yyyy hh:mm:ss");
        systemDateTest.setStringDate(simpleDateFormat.format(systemDateTest.getDate()));
        System.out.println(systemDateTest.getStringDate());
    }

    public Date getDate() {
        return new Date();
    }

    public String getStringDate() {
        return stringDate;
    }

    public void setStringDate(String stringDate) {
        this.stringDate = stringDate;
    }
}

Please add some information to your answer(s) to explain your code.
there is a method name getDate() by which u can get date obj after that apply SimpleDateFormat so that you can convert date according to your format which is defined in SimpleDateFormat constructor and set in StringDate method you can make it cached
E
Eren
   String str = "2000-12-12";
   Date dt = null;
   SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");

    try 
    {
         dt = formatter.parse(str);
    }
    catch (Exception e)
    {
    }

    JOptionPane.showMessageDialog(null, formatter.format(dt));

M
Martin

You can also use substring()

String date_s = "2011-01-18 00:00:00.0";
date_s.substring(0,10);

If you want a space in front of the date, use

String date_s = " 2011-01-18 00:00:00.0";
date_s.substring(1,11);

A
Anbuselvan Rocky

You could try Java 8 new date, more information can be found on the Oracle documentation.

Or you can try the old one

public static Date getDateFromString(String format, String dateStr) {

    DateFormat formatter = new SimpleDateFormat(format);
    Date date = null;
    try {
        date = (Date) formatter.parse(dateStr);
    } catch (ParseException e) {
        e.printStackTrace();
    }

    return date;
}

public static String getDate(Date date, String dateFormat) {
    DateFormat formatter = new SimpleDateFormat(dateFormat);
    return formatter.format(date);
}

R
Radim Köhler
private SimpleDateFormat dataFormat = new SimpleDateFormat("dd/MM/yyyy");

@Override
public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
    if(value instanceof Date) {
        value = dataFormat.format(value);
    }
    return super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
};

M
M--

remove one y form the format provide to:

SimpleDateFormat dt1 = new SimpleDateFormat("yyyyy-mm-dd");

It should be:

SimpleDateFormat dt1 = new SimpleDateFormat("yyyy-mm-dd");

Not exactly. You need the correct case too (no matter if you use the modern DateTimeFormatter or cling with the outdated SimpleDateFormat).
M
M--

We can convert Today's date in the format of 'JUN 12, 2020'.

String.valueOf(DateFormat.getDateInstance().format(new Date())));

R
Rajneesh Shukla
/**
 * Method will take Date in "MMMM, dd yyyy HH:mm:s" format and return time difference like added: 3 min ago
 *
 * @param date : date in "MMMM, dd yyyy HH:mm:s" format
 * @return : time difference
 */
private String getDurationTimeStamp(String date) {
    String timeDifference = "";

    //date formatter as per the coder need
    SimpleDateFormat sdf = new SimpleDateFormat("MMMM, dd yyyy HH:mm:s");
    TimeZone timeZone = TimeZone.getTimeZone("EST");
    sdf.setTimeZone(timeZone);
    Date startDate = null;
    try {
        startDate = sdf.parse(date);
    } catch (ParseException e) {
        MyLog.printStack(e);
    }

    //end date will be the current system time to calculate the lapse time difference
    Date endDate = new Date();

    //get the time difference in milliseconds
    long duration = endDate.getTime() - startDate.getTime();

    long diffInSeconds = TimeUnit.MILLISECONDS.toSeconds(duration);
    long diffInMinutes = TimeUnit.MILLISECONDS.toMinutes(duration);
    long diffInHours = TimeUnit.MILLISECONDS.toHours(duration);
    long diffInDays = TimeUnit.MILLISECONDS.toDays(duration);

    if (diffInDays >= 365) {
        int year = (int) (diffInDays / 365);
        timeDifference = year + mContext.getString(R.string.year_ago);
    } else if (diffInDays >= 30) {
        int month = (int) (diffInDays / 30);
        timeDifference = month + mContext.getString(R.string.month_ago);
    }
    //if days are not enough to create year then get the days
    else if (diffInDays >= 1) {
        timeDifference = diffInDays + mContext.getString(R.string.day_ago);
    }
    //if days value<1 then get the hours
    else if (diffInHours >= 1) {
        timeDifference = diffInHours + mContext.getString(R.string.hour_ago);
    }
    //if hours value<1 then get the minutes
    else if (diffInMinutes >= 1) {
        timeDifference = diffInMinutes + mContext.getString(R.string.min_ago);
    }
    //if minutes value<1 then get the seconds
    else if (diffInSeconds >= 1) {
        timeDifference = diffInSeconds + mContext.getString(R.string.sec_ago);
    } else if (timeDifference.isEmpty()) {
        timeDifference = mContext.getString(R.string.now);
    }

    return mContext.getString(R.string.added) + " " + timeDifference;
}

A
Arvind Kumar Avinash

java.time

The java.util Date-Time API and their formatting API, SimpleDateFormat are outdated and error-prone. It is recommended to stop using them completely and switch to the modern Date-Time API*.

Also, quoted below is a notice from the home page of Joda-Time:

Note that from Java SE 8 onwards, users are asked to migrate to java.time (JSR-310) - a core part of the JDK which replaces this project.

Solution using java.time, the modern Date-Time API:

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Locale;

public class Main {
    public static void main(String[] args) {
        String strDate = "2011-01-18 00:00:00.0";
        DateTimeFormatter dtfInput = DateTimeFormatter.ofPattern("u-M-d H:m:s.S", Locale.ENGLISH);
        LocalDateTime ldt = LocalDateTime.parse(strDate, dtfInput);
        // Alternatively, the old way:
        // LocalDateTime ldt = dtfInput.parse(strDate, LocalDateTime::from);

        LocalDate date = ldt.toLocalDate();
        System.out.println(date);
    }
}

Output:

2011-01-18

ONLINE DEMO

Some important notes about the solution:

java.time made it possible to call parse and format functions on the Date-Time type itself, in addition to the old way (i.e. calling parse and format functions on the formatter type, which is DateTimeFormatter in case of java.time API). The modern Date-Time API is based on ISO 8601 and does not require using a DateTimeFormatter object explicitly as long as the Date-Time string conforms to the ISO 8601 standards e.g. I have not used a DateTimeFormatter for the output because LocalDate#toString already returns the string in the required format. Here, you can use y instead of u but I prefer u to y.

Learn more about the modern Date-Time API from Trail: Date Time.

* For any reason, if you have to stick to Java 6 or Java 7, you can use ThreeTen-Backport which backports most of the java.time functionality to Java 6 & 7. If you are working for an Android project and your Android API level is still not compliant with Java-8, check Java 8+ APIs available through desugaring and How to use ThreeTenABP in Android Project.


p
pavel

Say you want to change 2019-12-20 10:50 AM GMT+6:00 to 2019-12-20 10:50 AM first of all you have to understand the date format first one date format is yyyy-MM-dd hh:mm a zzz and second one date format will be yyyy-MM-dd hh:mm a

just return a string from this function like.

public String convertToOnlyDate(String currentDate) {
    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd hh:mm a ");
    Date date;
    String dateString = "";
    try {
        date = dateFormat.parse(currentDate);
        System.out.println(date.toString()); 

        dateString = dateFormat.format(date);
    } catch (ParseException e) {
        e.printStackTrace();
    }
    return dateString;
}

This function will return your desire answer. If you want to customize more just add or remove component from the date format.


E
Emad Aljumaily

you have some wrong: SimpleDateFormat dt1 = new SimpleDateFormat("yyyyy-mm-dd");

first : should be new SimpleDateFormat("yyyy-mm-dd"); //yyyy 4 not 5 this display 02011, but yyyy it disply 2011

second: change your code like this new SimpleDateFormat("yyyy-MM-dd");

i hope help you


M
M--
SimpleDateFormat dt1 = new SimpleDateFormat("yyyy-mm-dd");

This date-time class was supplanted years ago by the modern java.time classes. Specifically DateTimeFormatter and DateTimeFormatterBuilder. Suggesting SimpleDateFormat in 2019 is poor advice.
Incorrect Your formatting codes here are wrong. hh is for hour.
Usually we expect some discussion or explanation. Stack Overflow is meant to be more than a snippet library.