JDK8 日期时间类Locate使用 和SimpleDateFormat 互转

import java.text.SimpleDateFormat;
import java.time.DayOfWeek;
import java.time.Instant;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.util.Calendar;
import java.util.Date;

/**

• 测试时间类的使用 ZoneId 时区
• Date: 2019-03-20
• @author zqm
  */

public class Demo {

   static  String stringD= "2019-05-05";
   public static void main(String[] args) {
    SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    DateTimeFormatter dateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
    DateTimeFormatter dateTimeFormatter1 = DateTimeFormatter.ofPattern("yyyy-MM-dd");
    DateTimeFormatter dateTimeFormatter2 = DateTimeFormatter.ofPattern("HH:mm:ss");
    LocalDate localDate1 = LocalDate.of(2019, 04, 01);
    LocalDate localDate2 = LocalDate.of(2019, 04, 11);
    LocalDate localDate = LocalDate.now();
   // LocalTime localTime = LocalTime.now();
    String a = LocalDateTime.now().format(dateTimeFormatter);
    System.out.println(a);
    System.out.println(localDate);
  System.out.println(localDate.plusDays(1).format(dateTimeFormatter1));
  System.out.println(LocalDateTime.now().with(DayOfWeek.MONDAY).format(dateTimeFormatter));
    //当前日期往后推一年
    System.out.println(localDate.plusYears(1));
    //当前日期往后推半年
    System.out.println(localDate.plusMonths(6));
    //往前推一天
    System.out.println(localDate.plusMonths(1));
    //往后推一个月
    System.out.println(localDate.plusMonths(-1));
    //起始时间
    System.out.println(localDate.atStartOfDay().format(dateTimeFormatter));
    //日期指定任意时间
    System.out.println(localDate.atTime(5,1).format(dateTimeFormatter));
    System.out.println(localDate.atTime(23,59,59).format(dateTimeFormatter));
    //月有多少天
    System.out.println(localDate.lengthOfMonth());
    Date date = LocalDateToUdate(localDate);
    //获取月的第几天
    System.out.println(localDate.getDayOfMonth());
    //一年的哪一天
    System.out.println(localDate.getDayOfYear());
    //获取月fen
    System.out.println(localDate.getMonthValue());
    System.out.println(localDate.isAfter(localDate1));
    System.out.println(localDate.isBefore(localDate2));
    LocalDateTime localDateTime = LocalDateTime.now();
    LocalTime localTime = LocalTime.now();
    System.out.println(localTime);
    String aaaa = localTime.format(dateTimeFormatter2);
    System.out.println(localTime.format(dateTimeFormatter2));
    Date date1 = LocalDateTimeToUdate(localDateTime);
    System.out.println(date1);
    System.out.println(simpleDateFormat.format(date1));
    Date date2 = LocalTimeToUdate(localDate, localTime);
    System.out.println(date2);
    
    if (aaaa.compareTo("13:15:00")>0){
        System.out.println(true);
    }

    System.out.println(DateToLocateDate(new Date()));
    System.out.println(localDateTime.format(dateTimeFormatter));

}

/**
 * LocateDateTime 转date
 */
private static Date LocalDateTimeToUdate(LocalDateTime localDateTime) {
    ZoneId zone = ZoneId.systemDefault();
    Instant instant = localDateTime.atZone(zone).toInstant();
    return Date.from(instant);
}

/**
 * LocateDate  转 date
 */
private static Date LocalDateToUdate(LocalDate localDate) {
    ZoneId zone = ZoneId.systemDefault();
    Instant instant = localDate.atStartOfDay().atZone(zone).toInstant();
    return Date.from(instant);
}

/**
 * LocateTime  转 date
 */
private static Date LocalTimeToUdate(LocalDate localDate, LocalTime localTime) {
    ZoneId zone = ZoneId.systemDefault();

    LocalDateTime localDateTime = LocalDateTime.of(localDate, localTime);
    Instant instant = localDateTime.atZone(zone).toInstant();
    return Date.from(instant);
}

/**
 * Date  转LocalDate
 */
private static LocalDate DateToLocateDate(Date date) {
    Instant instant = date.toInstant();
    ZoneId zoneId = ZoneId.systemDefault();
    LocalDateTime localDateTime = LocalDateTime.ofInstant(instant, zoneId);
    return localDateTime.toLocalDate();
}

/**
 * Date  转LocalDate
 */
private static LocalTime DateToLocateTime(Date date) {
    Instant instant = date.toInstant();
    ZoneId zoneId = ZoneId.systemDefault();
    LocalDateTime localDateTime = LocalDateTime.ofInstant(instant, zoneId);
    return localDateTime.toLocalTime();
}

/**
 * Date  转LocalDateTime
 */
private static LocalDateTime DateToLocateDateTime(Date date) {
    Instant instant = date.toInstant();
    ZoneId zoneId = ZoneId.systemDefault();
    return LocalDateTime.ofInstant(instant, zoneId);
}


/**
 * 获取第n天开始时间，00点00分00秒的时间
 * @param date 指定日期
 * @param amount 表示与指定日期相隔amount天，正数往前推amount天，负数指定日期往后推 0表示与指定日期相同一天
 * @return
 */
public static String getOneDayStartTime(Date date,int amount) {
    Calendar calendar = Calendar.getInstance();
    calendar.setTime(date);
    calendar.set(Calendar.HOUR_OF_DAY, 0);
    calendar.set(Calendar.MINUTE, 0);
    calendar.set(Calendar.SECOND, 0);
    calendar.add(Calendar.DATE, amount);
    SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    return simpleDateFormat.format(calendar.getTime());
}


/**
 * 获取一天的结束时间23：59：59
 * @param date
 * @param amount
 * @return
 */
public static String getOneDayEndTime(Date date,int amount) {
    Calendar calendar = Calendar.getInstance();
    calendar.setTime(date);
    calendar.set(Calendar.HOUR_OF_DAY, 23);
    calendar.set(Calendar.MINUTE, 59);
    calendar.set(Calendar.SECOND, 59);
    calendar.add(Calendar.DATE, amount);
    SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    return simpleDateFormat.format(calendar.getTime());
  }
}