How Do I Convert a String to a Date in Java?

The Problem

You don’t know how to convert a String to a Date in Java.

The Solution

The recommended way to convert a String to a Date in Java is to use the DateTimeFormatter class from java.time. The DateTimeFormatter class is thread-safe, making it a better choice for multithreaded environments.

However, DateTimeFormatter requires Java version 8 or later. For older Java versions, you can use the SimpleDateFormat class from the java.text package.

Using DateTimeFormatter

Here’s an example that demonstrates how to convert a String to a LocalDate using the DateTimeFormatter class:

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

public class Main {
    public static void main(String[] args) {
        String dateString = "2024-10-09";
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");
        LocalDate date = LocalDate.parse(dateString, formatter);
        System.out.println(date);
    }
}

This generates the following output:

2024-10-09

Using SimpleDateFormat

Here’s an example that demonstrates how to convert a String to a Date using the SimpleDateFormat class:

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

class Main {
    public static void main(String[] args) {
        String dateString = "2024-10-09";
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");

        try {
            Date date = formatter.parse(dateString);
            System.out.println("Converted Date: " + date); 
        } catch (ParseException e) {
            System.out.println("Invalid date format");
        }
    }
}

This generates the following output:

Converted Date: Mon Oct 09 00:00:00 UTC 2024

In this example, SimpleDateFormat is used to define the format of the input string (yyyy-MM-dd). The parse() method attempts to convert the string into a Date object. If the input string doesn’t match the expected format, a ParseException is thrown.

Note: The SimpleDateFormat class is not thread-safe, so you should avoid sharing instances across multiple threads.

Choosing a Date Format

The SimpleDateFormat and DateTimeFormatter classes allow you to define custom date formats, such as:

• dd/MM/yyyy for dates like 09/10/2024
• MM-dd-yyyy HH:mm:ss for dates with times, like 10-09-2024 14:00:00

Ensure the format you provide matches the input string to avoid ParseException errors.

The table below provides an overview of the available format pattern symbols for the DateTimeFormatter class:

Symbol	Meaning	Presentation	Examples
G	era	text	AD; Anno Domini; A
u	year	year	2004; 04
y	year-of-era	year	2004; 04
D	day-of-year	number	189
M/L	month-of-year	number/text	7; 07; Jul; July; J
d	day-of-month	number	10
Q/q	quarter-of-year	number/text	3; 03; Q3; 3rd quarter
Y	week-based-year	year	1996; 96
w	week-of-week-based-year	number	27
W	week-of-month	number	4
E	day-of-week	text	Tue; Tuesday; T
e/c	localized day-of-week	number/text	2; 02; Tue; Tuesday; T
F	week-of-month	number	3
a	am-pm-of-day	text	PM
h	clock-hour-of-am-pm (1-12)	number	12
K	hour-of-am-pm (0-11)	number	0
k	clock-hour-of-am-pm (1-24)	number	0
H	hour-of-day (0-23)	number	0
m	minute-of-hour	number	30
s	second-of-minute	number	55
S	fraction-of-second	fraction	978
A	milli-of-day	number	1234
n	nano-of-second	number	987654321
N	nano-of-day	number	1234000000
V	time-zone ID	zone-id	America/Los_Angeles; Z; -08:30
z	time-zone name	zone-name	Pacific Standard Time; PST
O	localized zone-offset	offset-O	GMT+8; GMT+08:00; UTC-08:00;
X	zone-offset ‘Z’ for zero	offset-X	Z; -08; -0830; -08:30; -083015; -08:30:15;
x	zone-offset	offset-x	+0000; -08; -0830; -08:30; -083015; -08:30:15;
Z	zone-offset	offset-Z	+0000; -0800; -08:00;