How do I parse a text string into date and time?

In this code snippet example you will learn how to parse a text string into an instance of LocalDate, LocalTime and LocalDateTime. All of these classes provide a parse() method that accept an argument of text string that represent a valid date and time information and convert it into the corresponding object.

If the text string passed into the parse() method is not representing a valid date or time information this method throws a RuntimeException of type DateTimeParseException exception. If you want to handle this exception then you should wrap your code inside a try-catch block.

Let’s see the code snippet below as an example:

package org.kodejava.example.datetime;

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.format.DateTimeParseException;

public class DateTimeParseDemo {
    public static void main(String[] args) {

        // Parse string "2014-09-12" into LocalDate instance.
        LocalDate date = LocalDate.parse("2014-09-12");

        // Parse string "17:51:15: into LocalTime instance.
        LocalTime time = LocalTime.parse("17:51:15");

        // Parse string "2014-09-12T17:51:15" into LocalDateTime instance.
        LocalDateTime dateTime = LocalDateTime.parse("2014-09-12T17:51:15");

        System.out.println("date     = " + date);
        System.out.println("time     = " + time);
        System.out.println("dateTime = " + dateTime);

        try {
            // When the string cannot be parse a RuntimeException of type
            // DateTimeParseException will be thrown.
            LocalDate date1 = LocalDate.parse("2014-02-31");
            System.out.println("date1     = " + date1);
        } catch (DateTimeParseException e) {
            e.printStackTrace();
        }
    }
}

Running this code snippet will produce the following result:

date     = 2014-09-12
time     = 17:51:15
dateTime = 2014-09-12T17:51:15
java.time.format.DateTimeParseException: Text '2014-02-31' could not be parsed: Invalid date 'FEBRUARY 31'
    at java.time.format.DateTimeFormatter.createError(DateTimeFormatter.java:1918)
    at java.time.format.DateTimeFormatter.parse(DateTimeFormatter.java:1853)
    at java.time.LocalDate.parse(LocalDate.java:400)
    at java.time.LocalDate.parse(LocalDate.java:385)
    at org.kodejava.example.datetime.DateTimeParseDemo.main(DateTimeParseDemo.java:35)
Caused by: java.time.DateTimeException: Invalid date 'FEBRUARY 31'
    at java.time.LocalDate.create(LocalDate.java:431)
    at java.time.LocalDate.of(LocalDate.java:269)
    at java.time.chrono.IsoChronology.resolveYMD(IsoChronology.java:560)
    at java.time.chrono.IsoChronology.resolveYMD(IsoChronology.java:123)
    at java.time.chrono.AbstractChronology.resolveDate(AbstractChronology.java:472)
    at java.time.chrono.IsoChronology.resolveDate(IsoChronology.java:492)
    at java.time.chrono.IsoChronology.resolveDate(IsoChronology.java:123)
    at java.time.format.Parsed.resolveDateFields(Parsed.java:351)
    at java.time.format.Parsed.resolveFields(Parsed.java:257)
    at java.time.format.Parsed.resolve(Parsed.java:244)
    at java.time.format.DateTimeParseContext.toResolved(DateTimeParseContext.java:331)
    at java.time.format.DateTimeFormatter.parseResolved0(DateTimeFormatter.java:1953)
    at java.time.format.DateTimeFormatter.parse(DateTimeFormatter.java:1849)
    ... 3 more

As we can see from the output above, parsing a text string of "2014-02-31" give us a DateTimeParseException because the 31 of February is not a valid date.

Wayan Saryada

Programmer, runner, recreational diver, live in the island of Bali, Indonesia. Mostly programming in Java, creating web based application with Spring Framework, Hibernate / JPA.

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