How to Convert a String to Java 8 LocalDate

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Java 8 LocalDate is a date without a time zone in the ISO-8601 calendar system.

LocalDate.parse() method can be used to convert a String to Java 8 LocalDate.

In this tutorial, you will learn different ways convert a String to Java 8 LocalDate object using the LocalDate.parse() method.

Using LocalDate.parse()

A ISO-8601 standard date format(“YYYY-MM-DD”) string can be directly converted to LocalDate using the LocalDate.parse(string) method.

This can be used when the default ISO-8601 Date standard is followed in your application.

To convert a String to LocalDate without any explicit formatter,

  • Invoke the LocalDate.parse(string) method passing the string
  • String should be matchig the ISO-8601 standard format.
  • An LocalDate object will be returned

Code

    LocalDate localDate = LocalDate.parse("2023-02-14");  
    System.out.println(localDate);  //2023-02-14

The parsed LocalDate value is printed in the default ISO-8601 standard format.

You can also use Predefined DateTimeFormatter options instead of custom patterns.

Custom format Using DateTimeFormatter

The Java 8 DateTimeFormatter can be used with the required date pattern to convert to a string to LocalDate using the LocalDate.parse(string, formatter) method.

This can be used when the default Date standard is not used, and a specific format is required to convert the String to LocalDate.

To convert a String to LocalDate using DateTimeFormatter,

  • Use DateTimeFormatter.ofPattern(“d/MM/yyyy”) method to define a custom pattern
  • Invoke the LocalDate.parse(string, formatter) method with the string and custom dateTimeFormatter.
  • An LocalDate Object will be returned.

Code

    final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("d/MM/yyyy");  
    LocalDate localDate = LocalDate.parse("14/02/2023", formatter);  
    System.out.println(localDate);  //2023-02-14

The DateTimeFormatter is used to understand the format(d/MM/yyyy) of the String, and after converting to LocalDate, it is printed in the default ISO-8601 standard format.

Using specific Locale conversion

The Locale specification is required to convert string to LocalDate specific to region.

In the below example, The pattern("E, MMM d yyyy") used only will work for Locale US and Locale.Europe and executing this on any other region will throw DateTimeParseException.

This can be used when region-specific conversion is required, and it is always good to have Locale based conversion to avoid DateTimeParseException.

To convert String to LocalDate specific to Locale,

  • Use DateTimeFormatter.ofPattern(“d/MM/yyyy”, Locale.US) method to define a custom pattern with Locale value
  • Invoke the LocalDate.parse(string, formatter)
  • An LocalDate object is returned.

Let us see an example, when specific Locale is set and not passed while parsing the string to LocalDate.

Code

    Locale.setDefault(Locale.FRANCE);  
    final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("E, MMM d yyyy");  
    LocalDate localDate = LocalDate.parse("Sat, Feb 18 2023", formatter);  
    System.out.println(localDate);  //Exception in thread "main" java.time.format.DateTimeParseException: Text 'Sat, Feb 18 2023' could not be parsed at index 0

The pattern passed is not accepted in Locale.FRANCE and conversion results in a DateTimeParseException. By providing Locale-specific information to the formatter, the conversion is successful as like below,

Code

    Locale.setDefault(Locale.FRANCE);  
    final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("E, MMM d yyyy", Locale.US);  
    LocalDate localDate = LocalDate.parse("Sat, Feb 18 2023", formatter);  
    System.out.println(localDate);  //2023-02-18

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