[JAVA] Date and time acquisition method using DateAndTime API

Overview

Implement the following pattern in Java and Kotlin (almost the same) with Date and Time API.

--Change date and time --Original format --ISO format --First date and time of the month --End of the month

Implementation example

Click here for Java's Utils class.

LocalDateUtils.java

import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.format.DateTimeFormatter;
import java.time.temporal.TemporalAdjusters;

public class LocalDateTimeUtils {
    private static final DateTimeFormatter YYYYMM_FORMAT = DateTimeFormatter.ofPattern("yyyyMM");

    //Change date and time
    public static LocalDateTime getDateTimeAfterOneYear(LocalDateTime dateTime) {
        return dateTime.plusYears(1);
    }

    //Original format
    public static String getYearAndMonth(LocalDateTime dateTime) {
        return dateTime.format(YYYYMM_FORMAT);
    }

    //ISO format example)2011-12-03
    public static String getIsoLocalDate(LocalDateTime dateTime) {
        return dateTime.format(DateTimeFormatter.ISO_LOCAL_DATE);
    }

    //First date and time of the month
    public static LocalDateTime getFirstDayDateTime(LocalDateTime dateTime) {
        return LocalDateTime.of(dateTime.with(TemporalAdjusters.firstDayOfMonth()).toLocalDate(), LocalTime.MIN);
    }

    //End of the month
    public static LocalDateTime getLastDayDateTime(LocalDateTime dateTime) {
        return LocalDateTime.of(dateTime.with(TemporalAdjusters.lastDayOfMonth()).toLocalDate(), LocalTime.MAX);
    }
}

Click here for Kotlin extension classes.

LocalDateTime.kt

import java.time.LocalDateTime
import java.time.LocalTime
import java.time.format.DateTimeFormatter
import java.time.temporal.TemporalAdjusters

private val YYYYMM_FORMAT = DateTimeFormatter.ofPattern("yyyyMM")

//Change date and time
fun LocalDateTime.getDateTimeAfterOneYear(): LocalDateTime = plusYears(1)

//Original format
fun LocalDateTime.getYearAndMonth(): String = format(YYYYMM_FORMAT)

//ISO format example)2011-12-03
fun LocalDateTime.getIsoLocalDate(): String = format(DateTimeFormatter.ISO_LOCAL_DATE)

//First date and time of the month
fun LocalDateTime.getFirstDayDateTime(): LocalDateTime = LocalDateTime.of(with(TemporalAdjusters.firstDayOfMonth()).toLocalDate(), LocalTime.MIN)

//End of the month
fun LocalDateTime.getLastDayDateTime(): LocalDateTime =  LocalDateTime.of(with(TemporalAdjusters.lastDayOfMonth()).toLocalDate(), LocalTime.MAX)