Using Java 8 java.time API: LocalDate, LocalTime, and LocalDateTime Examples

Before Java 8, developers often used java.util.Date, which has many drawbacks such as mutability, lack of thread safety, inconsistent definitions, and no time‑zone or internationalization support.

Java 8 introduced the java.time package, providing immutable classes like LocalDate, LocalTime, and LocalDateTime for handling dates and times without time‑zone complications.

LocalDate

LocalDate represents a date without a time component. The default format is yyyy‑MM‑dd.

Getting the current date and its year, month, and day:

// Get current date and its components
LocalDate localDate = LocalDate.now();
int year = localDate.getYear();
int month = localDate.getMonthValue();
int day = localDate.getDayOfMonth();
System.out.println("Current date: " + localDate);
System.out.println("Year: " + year + "  Month: " + month + "  Day: " + day);

Creating a specific date:

// Get a specific date
LocalDate specifiedDay = LocalDate.of(2008, 8, 18);
System.out.println("Specified date: " + specifiedDay);

Comparing two dates for equality or order:

LocalDate localDate = LocalDate.now();
LocalDate otherDate = LocalDate.of(2018, 11, 11);
if (localDate.equals(otherDate)) {
    System.out.println("localDate equals otherDate!");
} else {
    if (localDate.isAfter(otherDate)) {
        System.out.println("localDate is after otherDate!");
    }
    if (localDate.isBefore(otherDate)) {
        System.out.println("localDate is before otherDate!");
    }
}

Adding and subtracting years, months, weeks, or days:

LocalDate localDate = LocalDate.now();
System.out.println("Date after 2 years: " + localDate.plusYears(2));
System.out.println("Date after 6 months: " + localDate.plusMonths(6));
System.out.println("Date after 3 weeks: " + localDate.plusWeeks(3));
System.out.println("Date after 15 days: " + localDate.plusDays(15));
System.out.println("Date 2 years ago: " + localDate.minusYears(2));
System.out.println("Date 6 months ago: " + localDate.minusMonths(6));
System.out.println("Date 3 weeks ago: " + localDate.minusWeeks(3));
System.out.println("Date 15 days ago: " + localDate.minusDays(15));

Calculating the number of days between two dates:

// Get the 100th day of 2018
LocalDate specialDay = LocalDate.ofYearDay(2018, 100);
System.out.println("100th day of 2018: " + specialDay);
// Interval in days
long intervalDay = localDate.toEpochDay() - specialDay.toEpochDay();
System.out.println("Interval days: " + intervalDay);

LocalTime

LocalTime represents a time without a date component. The default format is HH:mm:ss.SSS.

Getting the current time and its hour, minute, second, and creating a custom time:

// Current time
LocalTime localTime = LocalTime.now();
int hour = localTime.getHour();
int minute = localTime.getMinute();
int second = localTime.getSecond();
System.out.println("Current time: " + localTime);
System.out.println("Hour: " + hour + "  Minute: " + minute + "  Second: " + second);
// Custom time
LocalTime specifiedTime = LocalTime.of(15, 30, 45);
System.out.println("Custom time: " + specifiedTime);

Comparing two times:

if (localTime.equals(specifiedTime)) {
    System.out.println("localTime equals specifiedTime!");
} else {
    if (localTime.isAfter(specifiedTime)) {
        System.out.println("localTime is after specifiedTime!");
    }
    if (localTime.isBefore(specifiedTime)) {
        System.out.println("localTime is before specifiedTime!");
    }
}

Adding and subtracting hours, minutes, and seconds:

System.out.println("Current time: " + localTime);
System.out.println("After 2 hours: " + localTime.plusHours(2));
System.out.println("After 30 minutes: " + localTime.plusMinutes(30));
System.out.println("After 500 seconds: " + localTime.plusSeconds(500));
System.out.println("2 hours ago: " + localTime.minusHours(2));
System.out.println("30 minutes ago: " + localTime.minusMinutes(30));
System.out.println("500 seconds ago: " + localTime.minusSeconds(500));

LocalDateTime

LocalDateTime combines date and time in an immutable object. The default format is yyyy‑MM‑ddTHH:mm:ss.SSS.

Getting the current date‑time and creating a custom one from LocalDate and LocalTime:

// Current date‑time
LocalDateTime localDateTime = LocalDateTime.now();
System.out.println("Current date‑time: " + localDateTime);
// Custom date‑time
LocalDateTime specifiedDateTime = LocalDateTime.of(LocalDate.now(), LocalTime.now());
System.out.println("Custom date‑time: " + specifiedDateTime);

Converting a LocalDateTime to separate LocalDate and LocalTime objects:

LocalDate datePart = localDateTime.toLocalDate();
LocalTime timePart = localDateTime.toLocalTime();
System.out.println("Current date: " + datePart);
System.out.println("Current time: " + timePart);