Convert String to Date – Java

In this tutorial, we will show you how to convert a String to java.util.Date. Many Java beginners are stuck in the Date conversion, hope this summary guide will helps you in some ways.

    // String -> Date
    SimpleDateFormat.parse(String);

    // Date -> String
    SimpleDateFormat.format(date);

Refer to table below for some of the common date and time patterns used in java.text.SimpleDateFormat, refer to this JavaDoc

Letter	Description	Examples
y	Year	2013
M	Month in year	July, 07, 7
d	Day in month	1-31
E	Day name in week	Friday, Sunday
a	Am/pm marker	AM, PM
H	Hour in day	0-23
h	Hour in am/pm	1-12
m	Minute in hour	0-60
s	Second in minute	0-60

Note
You may interest at this Java 8 example – How to convert String to LocalDate

1. String = 7-Jun-2013

If 3 ‘M’, then the month is interpreted as text (Mon-Dec), else number (01-12).

TestDateExample1.java

package com.mkyong.date;

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

public class TestDateExample1 {

    public static void main(String[] argv) {

        SimpleDateFormat formatter = new SimpleDateFormat("dd-MMM-yyyy");
        String dateInString = "7-Jun-2013";

        try {

            Date date = formatter.parse(dateInString);
            System.out.println(date);
            System.out.println(formatter.format(date));

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

    }

}

Output

Fri Jun 07 00:00:00 MYT 2013
07-Jun-2013

2. String = 07/06/2013

TestDateExample2.java

package com.mkyong.date;

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

public class TestDateExample2 {

    public static void main(String[] argv) {

        SimpleDateFormat formatter = new SimpleDateFormat("dd/MM/yyyy");
        String dateInString = "07/06/2013";

        try {

            Date date = formatter.parse(dateInString);
            System.out.println(date);
            System.out.println(formatter.format(date));

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

    }

}

Output

Fri Jun 07 00:00:00 MYT 2013
07/06/2013

3. String = Fri, June 7 2013

TestDateExample3.java

package com.mkyong.date;

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

public class TestDateExample3 {

    public static void main(String[] argv) {

        SimpleDateFormat formatter = new SimpleDateFormat("E, MMM dd yyyy");
        String dateInString = "Fri, June 7 2013";

        try {

            Date date = formatter.parse(dateInString);
            System.out.println(date);
            System.out.println(formatter.format(date));

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

    }

}

Output

Fri Jun 07 00:00:00 MYT 2013
Fri, Jun 07 2013

4. String = Friday, Jun 7, 2013 12:10:56 PM

TestDateExample4.java

package com.mkyong.date;

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

public class TestDateExample4 {

    public static void main(String[] argv) {

        SimpleDateFormat formatter = new SimpleDateFormat("EEEE, MMM dd, yyyy HH:mm:ss a");
        String dateInString = "Friday, Jun 7, 2013 12:10:56 PM";

        try {

            Date date = formatter.parse(dateInString);
            System.out.println(date);
            System.out.println(formatter.format(date));

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

    }

}

Output

Fri Jun 07 12:10:56 MYT 2013
Friday, Jun 07, 2013 12:10:56 PM

5. String = 2014-10-05T15:23:01Z

Z suffix means UTC, java.util.SimpleDateFormat doesn’t parse it correctly, you need to replace the suffix Z with ‘+0000’.

TestDateExample5.java

package com.mkyong.date;

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

public class TestDateExample5 {

    public static void main(String[] argv) {

        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ");
        String dateInString = "2014-10-05T15:23:01Z";

        try {

            Date date = formatter.parse(dateInString.replaceAll("Z$", "+0000"));
            System.out.println(date);

            System.out.println("time zone : " + TimeZone.getDefault().getID());
            System.out.println(formatter.format(date));

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

    }

}

Output

Sun Oct 05 23:23:01 MYT 2014
time zone : Asia/Kuala_Lumpur
2014-10-05T23:23:01+0800

In Java 8, you can convert it into a java.time.Instant object, and display it with a specified time zone.

TestDateExample6.java

package com.mkyong.date;

import java.time.*;

public class TestDateExample6 {

    public static void main(String[] argv) {

        String dateInString = "2014-10-05T15:23:01Z";

        Instant instant = Instant.parse(dateInString);

        System.out.println(instant);

        //get date time only
        LocalDateTime result = LocalDateTime.ofInstant(instant, ZoneId.of(ZoneOffset.UTC.getId()));

        System.out.println(result);

        //get date time + timezone
        ZonedDateTime zonedDateTime = instant.atZone(ZoneId.of("Africa/Tripoli"));
        System.out.println(zonedDateTime);

        //get date time + timezone
        ZonedDateTime zonedDateTime2 = instant.atZone(ZoneId.of("Europe/Athens"));
        System.out.println(zonedDateTime2);
        
    }

}

Output

2014-10-05T15:23:01Z
2014-10-05T15:23:01
2014-10-05T17:23:01+02:00[Africa/Tripoli]
2014-10-05T18:23:01+03:00[Europe/Athens]

6.String = 2019/4/1 13:00:00 PM

        String d = "2019/4/1 13:00:00 PM";
        DateTimeFormatter builder = DateTimeFormat.forPattern("yyyy/MM/dd HH:mm:ss a").withLocale(Locale.ENGLISH);
        System.out.println(builder.parseDateTime(d).toString("yyyy-MM-dd HH:mm:ss"));

output:

2019/4/1 13:00:00

References

来源：oschina

链接：https://my.oschina.net/u/2391658/blog/3123068

标签

java

Joda-Time