In Java (starting from Java 8), you can format dates using the DateTimeFormatter class, which provides an easier and more modern approach to date and time formatting. This class is part of the java.time.format package and works seamlessly with the java.time API (e.g., LocalDate, LocalDateTime, ZonedDateTime).

Here’s how you can format dates with DateTimeFormatter:

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Example of Formatting Dates with DateTimeFormatter

package org.kodejava.datetime;

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;

public class DateTimeFormatterExample {
   public static void main(String[] args) {
      // Get the current date and time
      LocalDateTime currentDateTime = LocalDateTime.now();

      // Define a formatter with a custom pattern
      DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy HH:mm:ss");

      // Format the date and time
      String formattedDateTime = currentDateTime.format(formatter);

      // Print the result
      System.out.println("Formatted Date and Time: " + formattedDateTime);
   }
}

Example Output:

Formatted Date and Time: 02/08/2025 15:52:30

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Common Patterns for Date and Time

Here are the most commonly used symbols for formatting patterns with DateTimeFormatter:

Symbol	Meaning	Example
y	Year	2025
M	Month	08 or August
d	Day of the month	02
E	Day name in a week	Tue
H	Hour (0-23)	15
h	Hour (1-12, AM/PM)	3
m	Minute in hour	45
s	Second in minute	30
a	AM/PM	PM
z	Time zone name	PDT
'text'	Literal text	‘at’

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Example with Fully Custom Pattern

package org.kodejava.datetime;

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;

public class CustomDateFormatting {
   public static void main(String[] args) {
      LocalDate currentDate = LocalDate.now();

      // Custom date format
      DateTimeFormatter formatter = DateTimeFormatter.ofPattern("EEEE, MMMM dd yyyy");
      String formattedDate = currentDate.format(formatter);

      // Print the formatted date
      System.out.println("Custom Formatted Date: " + formattedDate);
   }
}

Output:

Custom Formatted Date: Saturday, August 02 2025

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Predefined Formatters in DateTimeFormatter

DateTimeFormatter also provides several predefined, common formatters:

Formatter	Pattern	Example
DateTimeFormatter.ISO_DATE	yyyy-MM-dd	2025-08-02
DateTimeFormatter.ISO_TIME	HH:mm:ss	15:45:30
DateTimeFormatter.ISO_DATE_TIME	yyyy-MM-dd'T'HH:mm:ss	2025-08-02T15:45:30
DateTimeFormatter.BASIC_ISO_DATE	yyyyMMdd	20250802
DateTimeFormatter.RFC_1123_DATE_TIME	RFC 1123 format	Sat, 02 Aug 2025 15:45:30

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Example: Formatting Dates with Time Zones

package org.kodejava.datetime;

import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;

public class ZonedDateTimeFormatterExample {
   public static void main(String[] args) {
      // Get the current date and time with time zone
      ZonedDateTime zonedDateTime = ZonedDateTime.now();

      // Define a formatter with a custom pattern that includes the time zone
      DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy HH:mm:ss z Z");

      // Format the ZonedDateTime
      String formattedDateTime = zonedDateTime.format(formatter);

      // Print the result
      System.out.println("Formatted Date and Time with Time Zone: " + formattedDateTime);
   }
}

Output:

Formatted Date and Time with Time Zone: 02/08/2025 15:50:30 PDT -0700

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Explanation of Pattern:

• z: Displays the short name of the time zone (e.g., PDT, GMT).
• Z: Displays the time zone offset (e.g., -0700).

Parsing and Formatting Specific Time Zones

You can work with specific time zones using the ZoneId class:

package org.kodejava.datetime;

import java.time.ZonedDateTime;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;

public class SpecificTimeZoneExample {
   public static void main(String[] args) {
      // Get the current date and time in a specific time zone
      ZonedDateTime zonedDateTime = ZonedDateTime.now(ZoneId.of("Europe/London"));

      // Define a formatter
      DateTimeFormatter formatter = DateTimeFormatter.ofPattern("EEEE, MMM dd yyyy HH:mm:ss z");

      // Format the ZonedDateTime
      String formattedDateTime = zonedDateTime.format(formatter);

      // Print the result
      System.out.println("London Time: " + formattedDateTime);
   }
}

Output:

London Time: Saturday, Aug 02 2025 23:50:30 BST

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Predefined Formatter for Time Zones

If you’d like to use the predefined formatters to format dates with time zones, you can try:

package org.kodejava.datetime;

import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;

public class PredefinedTimeZoneFormatter {
   public static void main(String[] args) {
      // Get the current ZonedDateTime
      ZonedDateTime zonedDateTime = ZonedDateTime.now();

      // Use a predefined formatter
      String formattedDateTime = zonedDateTime.format(DateTimeFormatter.RFC_1123_DATE_TIME);

      // Print the result
      System.out.println("Formatted with Predefined Formatter: " + formattedDateTime);
   }
}

Output:

Formatted with Predefined Formatter: Sat, 02 Aug 2025 15:50:30 -0700

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Notes:

1. Thread Safety:
   Unlike SimpleDateFormat, DateTimeFormatter is thread-safe and can be safely used in concurrent environments.

2. Extensible Patterns:
   You can use literal text in the patterns by enclosing it in single quotes ('text').

3. Working with Time Zones:
   If you are working with time zones, you can use ZonedDateTime or OffsetDateTime along with a DateTimeFormatter.

4. ZoneId Use:
   You can specify almost any valid time zone using ZoneId.of("Zone_Name"). Example: "America/New_York", "Asia/Tokyo", "Australia/Sydney".

5. Daylight Saving Time:
   Time zones take daylight saving time into account automatically if applicable.
6. Predefined Formatters with Zones:
   Predefined formatters like DateTimeFormatter.ISO_ZONED_DATE_TIME and DateTimeFormatter.RFC_1123_DATE_TIME are handy for common time zone formats.