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Java Parsing Dates

Parsing turns date text into a date value. A DateTimeFormatter with a pattern tells the parser the shape of the text.

Parse day-first text

The pattern reads 15/01/2026 as day 15, month 1, year 2026. The parsed date prints in ISO order.

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
public class Main {
  public static void main(String[] args) {
    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy");
    LocalDate date = LocalDate.parse("15/01/2026", formatter);
    System.out.println(date);
  }
}

Print back through the same pattern

Formatting runs the conversion the other way. The same formatter turns the date back into day-first text.

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
public class Main {
  public static void main(String[] args) {
    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy");
    LocalDate date = LocalDate.parse("15/01/2026", formatter);
    System.out.println(date.format(formatter));
  }
}

Wrong-shape text is caught

The text 2026-01-15 does not match the day-first pattern, so the parse fails. The catch block prints a plain message.

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.time.format.DateTimeParseException;
public class Main {
  public static void main(String[] args) {
    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy");
    try {
      LocalDate date = LocalDate.parse("2026-01-15", formatter);
      System.out.println(date);
    } catch (DateTimeParseException e) {
      System.out.println("That text is not in day/month/year order.");
    }
  }
}

A date-time taste

The pattern gains an hour and a minute after the date parts. The parsed value prints with a T between date and time.

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
public class Main {
  public static void main(String[] args) {
    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy HH:mm");
    LocalDateTime moment = LocalDateTime.parse("15/01/2026 10:30", formatter);
    System.out.println(moment);
  }
}

Example

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
public class Main {
  public static void main(String[] args) {
    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy");
    LocalDate date = LocalDate.parse("03/04/2026", formatter);
    System.out.println(date);
    System.out.println(date.format(formatter));
    System.out.println(date.plusDays(7).format(formatter));
  }
}

Key points

  • LocalDate.parse reads date text with a DateTimeFormatter.
  • The pattern dd/MM/yyyy means two-digit day, two-digit month, and four-digit year.
  • The format method prints a date back through the same pattern.
  • Text in the wrong shape throws DateTimeParseException.
  • A catch block for DateTimeParseException can print a plain message of the program’s own.
  • A date-time pattern adds hours and minutes after the date parts.

In this example, the text 03/04/2026 parses to April 3, 2026, and formats back to the same day-first text. Adding seven days and formatting again gives April 10, 2026.

Try it Yourself

Edit the code, then press Run.

Running is simulated

Exercise

Which pattern reads a day-first date like 15/01/2026?