Java programming time date API instance resolution

The examples in this paper are mainly about the new feature in Java8, the relevant examples of time and date api, as follows:

package com.effective.common.base.date;
import java.time.Instant;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.Period;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.time.temporal.ChronoUnit;
import java.util.Date;
/**
 *  Date tool class 
 * @author yanweiqi
 * @since 2016-5-6
 *
 */
public class LocalDateUtils {
	private static ZoneId zone = ZoneId.systemDefault();
	/**
   *  The string to turn Date
   * @param date
   * @return
   * @throws Exception
   */
	public static Date convertToDate(String date) throws Exception{
		LocalDate localDate = null;
		if(null == date){
			throw new NullPointerException("date isn't null");
		} else {
			localDate = LocalDate.parse(date);
			return convertToDate(localDate);
		}
	}
	/**
   *  The string to turn LocalDateTime
   * @param date
   * @return localDateTime
   */
	public static LocalDateTime convertToLocalDateTime(String date){
		LocalDateTime localDateTime = null;
		if(null == date){
			throw new NullPointerException("date isn't null");
		} else {
			localDateTime = LocalDateTime.parse(date);
			return localDateTime;
		}
	}
	/**
   * LocalDate turn Date
   * @param localDate
   * @return Date
   */
	public static Date convertToDate(LocalDate localDate){
		Instant instant = localDate.atStartOfDay().atZone(zone).toInstant();
		return Date.from(instant);
	}
	/**
   * LocalDate turn Date
   * @param localDateTime
   * @return Date
   */
	public static Date convertToDate(LocalDateTime localDateTime){
		Instant instant = localDateTime.atZone(zone).toInstant();
		return Date.from(instant);
	}
	/**
   * Date turn LocalDate
   * @param date
   * @return localDate
   */
	public static LocalDate convertToLocalDate(Date date){
		Instant instant = date.toInstant();
		return convertToLocalDateTime(instant).toLocalDate();
	}
	/**
   * Date turn LocalTime
   * @param date
   * @return localDate
   */
	public static LocalTime convertToLocalTime(Date date){
		Instant instant = date.toInstant();
		return convertToLocalDateTime(instant).toLocalTime();
	}
	/**
   * Date turn LocalDatetime
   * @param date
   * @return localDate
   */
	public static LocalDateTime convertToLocalDateTime(Date date){
		Instant instant = date.toInstant();
		return convertToLocalDateTime(instant);
	}
	/**
   * Instant turn LocalDateTime
   * @param instant
   * @return
   */
	public static LocalDateTime convertToLocalDateTime(Instant instant){
		return LocalDateTime.ofInstant(instant, zone);
	}
	/**
   * LocalDateTime turn Instant
   * @param localDateTime
   * @return
   */
	public static Instant convertToInstant(LocalDateTime localDateTime){
		return localDateTime.atZone(zone).toInstant();
	}
	/**
   * LocalDate turn Instant
   * @param localDate
   * @return
   */
	public static Instant convertToInstant(LocalDate localDate){
		return localDate.atStartOfDay(zone).toInstant();
	}
	/**
   * LocalDate turn LocalDateTime
   * @param localDate
   * @return LocalDateTime
   */
	public static LocalDateTime convertToLocalDateTime(LocalDate localDate){
		return localDate.atStartOfDay();
	}
	/**
   *  Daily cycle formatting 
   * @param localDateTime
   * @param formatStyle
   * @return
   */
	public static String formatter(LocalDateTime localDateTime, String formatStyle){
		return DateTimeFormatter.ofPattern(formatStyle).format(localDateTime);
	}
	/**
   *  Set up in 
   * @param sourceDate
   * @param year
   * @return LocalDateTime
   */
	public static LocalDateTime setYear(LocalDateTime sourceDate, Integer year){
		return sourceDate.withYear(year);
	}
	/**
   *  Set the month 
   * @param sourceDate
   * @param month
   * @return LocalDateTime
   */
	public static LocalDateTime setMonth(LocalDateTime sourceDate, Integer month){
		return sourceDate.withMonth(month);
	}
	/**
   *  Set the day 
   * @param sourceDate
   * @param month
   * @return LocalDateTime
   */
	public static LocalDateTime setDayOfMonth(LocalDateTime sourceDate, Integer dayOfMonth){
		return sourceDate.withDayOfMonth(dayOfMonth);
	}
	/**
   *  Set hours 
   * @param sourceDate
   * @param hour
   * @return
   */
	public static LocalDateTime setHour(LocalDateTime sourceDate,Integer hour){
		return sourceDate.withHour(hour);
	}
	/**
   *  Set the minutes 
   * @param sourceDate
   * @param minute
   * @return
   */
	public static LocalDateTime setMinute(LocalDateTime sourceDate,Integer minute){
		return sourceDate.withMinute(minute);
	}
	/**
   *  Set up the second 
   * @param sourceDate
   * @param second
   * @return
   */
	public static LocalDateTime setSecond(LocalDateTime sourceDate,Integer second){
		return sourceDate.withSecond(second);
	}
	/**
   *  Modify the date of year 
   * @param sourceDate
   * @param year
   * @param month
   * @param dayOfMonth
   * @return
   */
	public static LocalDateTime setYMD(LocalDateTime sourceDate, Integer year, Integer month, Integer dayOfMonth) {
		return sourceDate.withYear(year).withMonth(month).withDayOfMonth(dayOfMonth);
	}
	/**
   *  Seconds for modification 
   * @param sourceDate
   * @param hour
   * @param minute
   * @param second
   * @return
   */
	public static LocalDateTime setHMS(LocalDateTime sourceDate,Integer hour, Integer minute, Integer second) {
		return sourceDate.withHour(hour).withMinute(minute).withSecond(second);
	}
	/**
   *  Calculate the number of days of difference 
   * @param beginDate
   * @param endDate
   * @return
   */
	public static int getInteverDays(LocalDate beginDate,LocalDate endDate){
		Period period = Period.between(beginDate, endDate);
		return period.getDays();
	}
	/**
   *  The date to add and subtract 
   * @param num  The number of 
   * @param unit  unit 
   * @param LocalDate  The original date 
   * @return LocalDate  The date after the increment 
   */
	@SuppressWarnings("static-access")
	  public static LocalDate addLocalDate(long num,ChronoUnit unit,final LocalDate localDate){
		LocalDate resultDate;
		if(num > 0){
			resultDate = localDate.now().plus(num, unit);
		} else {
			resultDate = localDate.now().minus(Math.abs(num), unit);
		}
		return resultDate;
	}
	/**
   *  The date is in minutes and seconds 
   * @param num  The number of 
   * @param unit  unit 
   * @param localDateTime  The original date 
   * @return LocalDateTime  The date after the increment 
   */
	@SuppressWarnings("static-access")
	  public static LocalDateTime addLocalDateTime(long num,ChronoUnit unit,LocalDateTime localDateTime){
		LocalDateTime resultDateTime;
		if(num > 0){
			resultDateTime = localDateTime.now().plus(num, unit);
		} else {
			resultDateTime = localDateTime.now().minus(Math.abs(num),unit);
		}
		return resultDateTime;
	}
	/**
   *  Time minutes plus or minus seconds 
   * @param num  The number of 
   * @param unit  unit 
   * @param localTime  The original date 
   * @return LocalDateTime  The date after the increment 
   */
	@SuppressWarnings("static-access")
	  public static LocalTime addLocalTime(long num,ChronoUnit unit,LocalTime localTime){
		LocalTime resultTime;
		if(num > 0){
			resultTime = localTime.now().plus(num, unit);
		} else {
			resultTime = localTime.now().minus(Math.abs(num), unit);
		}
		return resultTime;
	}
	public static void main(String[] args){
		LocalDateTime time = LocalDateTime.now();
		String rr = formatter(time, "yyyy-MM-dd HH:mm:ss");
		System.out.println(rr);
		LocalDateTime time2 = addLocalDateTime(-2, ChronoUnit.HOURS, time);
		String yy = formatter(time2, "yyyy-MM-dd HH:mm:ss");
		System.out.println(yy);
	}

The code involves the use of time and date class and other content, with a simple comment, you can reference.

conclusion

That is the end of this article on Java programming time date API instance parsing, I hope to help you. Interested friends can continue to refer to other related topics in this site, if there is any deficiency, welcome to comment out. Thank you for your support!