Java date util date to string format

Guide to java.util.Date Class

Learn to create new date, get current date, parse date to string or format Date object using java.util.Date class. These usecases are frequently required, and having them in one place will help in saving time for many of us.

It is worth noting that there is no timezone information associated with Date instance. A Date instance represents the time spent since Epach in milliseconds. If we print the date instance, it always prints the default or local timezone of the machine. So the timezone information printed in Date.toString() method should not misguide you.

1. Formatting a Date to String

Java program of formatting Date to string using SimpleDateFormat.format() . Please note that SimpleDateFormat is not a thread-safe class, so we should not share its instance with multiple threads.

SimpleDateFormat sdf = new SimpleDateFormat("dd/M/yyyy"); String date = sdf.format(new Date());

Refer SimpleDateFormat JavaDoc for detailed date and time patterns. Below is a list of the most common pattern letters you can use.

y = year (yy or yyyy) M = month (MM) d = day in month (dd) h = hour (0-12) (hh) H = hour (0-23) (HH) m = minute in hour (mm) s = seconds (ss) S = milliseconds (SSS) z = time zone text (e.g. Pacific Standard Time. ) Z = time zone, time offset (e.g. -0800)

Pattern	Example
yyyy-MM-dd (ISO)	“2018-07-14”
dd-MMM-yyyy	“14-Jul-2018”
dd/MM/yyyy	“14/07/2018”
E, MMM dd yyyy	“Sat, Jul 14 2018”
h:mm a	“12:08 PM”
EEEE, MMM dd, yyyy HH:mm:ss a	“Saturday, Jul 14, 2018 14:31:06 PM”
yyyy-MM-dd’T’HH:mm:ssZ	“2018-07-14T14:31:30+0530”
hh ‘o»clock’ a, zzzz	“12 o’clock PM, Pacific Daylight Time”
K:mm a, z	“0:08 PM, PDT”

2. Parsing a String to Date

Java program of parsing a string to Date instance using SimpleDateFormat.parse() method.

SimpleDateFormat sdf = new SimpleDateFormat("dd-M-yyyy hh:mm:ss"); String dateInString = "15-10-2015 10:20:56"; Date date = sdf.parse(dateInString);

3. Getting Current Date and Time

java.util.Date class represents the date and time elapsed since the epoch. Given below are the Java programs for getting the current date and time and printing in a given format.

SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss"); Date date = new Date(); System.out.println(dateFormat.format(date)); 

For reference, since Java 8, we can use LocalDate , LocalTime and LocalDateTime classes.

LocalDate today = LocalDate.now(); System.out.println("Today's Local date : " + today); LocalTime time = LocalTime.now(); System.out.println("local time now : " + time);

4. Convert between Date and Calendar

4.1. Converting Calendar to Date

Calendar calendar = Calendar.getInstance(); Date date = calendar.getTime();

4.2. Converting Date to Calendar

SimpleDateFormat sdf = new SimpleDateFormat("dd-M-yyyy hh:mm:ss"); String dateInString = "27-04-2016 10:22:56"; Date date = sdf.parse(dateInString); Calendar calendar = Calendar.getInstance(); calendar.setTime(date); 

We can compare two two date instances using its compareTo() method. It returns an integer value representing given date is before or after another date.

The comparison date1.CompareTo(date2) will return:

• a value 0 if date2 is equal to date1;
• a value less than 0 if date1 is before date2;
• a value greater than 0 if date1 is after date2.

Date date1 = new Date(); Date date2 = new Date(); int comparison = date1.compareTo(date2);

6. Extracting Days, Months and Years

Java program to get date parts such as year, month, etc separately.

The methods to get the year, month, day of the month, hour, etc. are deprecated. If you need to get or set the year, month, day of the month, etc. use a java.util.Calendar instead.

Calendar calendar = Calendar.getInstance(); calendar.setTime(new Date()); int year = calendar.get(Calendar.YEAR); int month = calendar.get(Calendar.MONTH); int dayOfMonth = calendar.get(Calendar.DAY_OF_MONTH); // Jan = 0, not 1 int dayOfWeek = calendar.get(Calendar.DAY_OF_WEEK); int weekOfYear = calendar.get(Calendar.WEEK_OF_YEAR); int weekOfMonth= calendar.get(Calendar.WEEK_OF_MONTH); int hour = calendar.get(Calendar.HOUR); // 12 hour clock int hourOfDay = calendar.get(Calendar.HOUR_OF_DAY); // 24 hour clock int minute = calendar.get(Calendar.MINUTE); int second = calendar.get(Calendar.SECOND); int millisecond= calendar.get(Calendar.MILLISECOND);

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Convert Date to String in Java

1. Convert Date to String Using SimpleDateFormat in Java
2. Convert Date to String Using DateFormatUtils Class in Java
3. Convert Date to String Using DateTimeFormatter in Java
4. Convert Date to String With the Time Zone in Java
5. Convert Date to String With String Class in Java

This tutorial introduces how to convert java.util.Date to String in Java and lists some example codes to understand it.

Java has several classes and methods that help convert Date to String like using SimpleDateFormat , DateFormatUtils , and DateTimeFormatter class.

Convert Date to String Using SimpleDateFormat in Java

Here, We use format() method of SimpleDateFormat class to get String from the util.Date object in Java.

import java.text.DateFormat; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date;  public class SimpleTesting    public static void main(String[] args) throws ParseException   DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss");  Date date = new Date();  String dateToStr = dateFormat.format(date);  System.out.println("Date is "+ dateToStr);  > > 

Convert Date to String Using DateFormatUtils Class in Java

If you are using the Apache library then use format() method of DateFormateUtils class. It returns a string after converting java.util.Date to string in Java.

import java.text.ParseException; import java.util.Date; import org.apache.commons.lang3.time.DateFormatUtils;  public class SimpleTesting    public static void main(String[] args) throws ParseException   Date date = new Date();  String dateToStr = DateFormatUtils.format(date, "yyyy-MM-dd HH:mm:SS");  System.out.println("Date is "+ dateToStr);  > > 

Convert Date to String Using DateTimeFormatter in Java

Here, we use the format() method that takes the ofPattern() method as an argument and returns a string representation of a date. See the example below.

import java.text.ParseException; import java.time.ZoneOffset; import java.time.format.DateTimeFormatter; import java.util.Date;  public class SimpleTesting    public static void main(String[] args) throws ParseException   Date date = new Date();  String dateToStr = date.toInstant()  .atOffset(ZoneOffset.UTC)  .format( DateTimeFormatter.ofPattern("dd-MM-yyyy"));  System.out.println("Date is "+ dateToStr);  > > 

Convert Date to String With the Time Zone in Java

Here, we use format() method of the DateTimeFormatter class to get string after conversion from java.util.date . We get time zone along with date because we specified the date-time format in the ofPattern() method.

import java.text.ParseException; import java.time.ZoneId; import java.time.format.DateTimeFormatter; import java.util.Date;  public class SimpleTesting    public static void main(String[] args) throws ParseException   Date date = new Date();  DateTimeFormatter format = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss:SSS Z")  .withZone(ZoneId.systemDefault());  String dateToStr = format.format(date.toInstant());  System.out.println("Date is "+ dateToStr);  > > 

Date is 2020-09-21 09:10:23:991 +0530 

Convert Date to String With String Class in Java

This is one of the simplest solutions to get a String of java.util.date object. Here, we use the format() method of the String class that formats the date based on the specified format. See the example below.

import java.text.ParseException; import java.util.Date;  public class SimpleTesting    public static void main(String[] args) throws ParseException   Date date = new Date();  String dateToStr = String.format("%1$tY-%1$tm-%1$td", date);  System.out.println("Date is "+ dateToStr);  > > 

Related Article — Java String

Related Article — Java DateTime

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