LocalDateTime日期格式化和指定日期的时分秒

LocalDateTime日期格式化和指定日期的时分秒

package com.example.core.mydemo.date;

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;

/**
 * now=2023-06-30
 * after=2023-07-04
 * afterTime=2023-07-04T00:00:01
 * dateFormat=06/30-07/01
 */
public class LocalDateTest {
    public static final String YYYYMMDDHHMMSSS_PATTERN = "yyyyMMddHHmmss";
    public static final String DEFAULT_PATTERN_NEW_SHORT = "MM/dd";

    public static void main(String[] args) {
        LocalDate now = LocalDate.now();
        LocalDate after = now.plusDays(4);
        LocalDateTime afterTime = after.atTime(0,0,1);

        System.out.println("now=" + now);
        System.out.println("after=" + after);
        System.out.println("afterTime=" + afterTime);

        String startTime = "20230630163000";
        String endTime = "20230701163000";
        LocalDateTime startLdt = parseStringToDateTime(startTime,YYYYMMDDHHMMSSS_PATTERN);
        LocalDateTime endLdt = parseStringToDateTime(endTime,YYYYMMDDHHMMSSS_PATTERN);
        String rentStr = formatDateTime(startLdt,DEFAULT_PATTERN_NEW_SHORT);
        String revertStr = formatDateTime(endLdt,DEFAULT_PATTERN_NEW_SHORT);
        String rentViewFormat = rentStr + "-" + revertStr;
        System.out.println("dateFormat=" + rentViewFormat);

    }

    public static LocalDateTime parseStringToDateTime(String time, String format) {
        DateTimeFormatter df = DateTimeFormatter.ofPattern(format);
        return LocalDateTime.parse(time, df);
    }

    public static String formatDateTime(LocalDateTime dateTime, String pattern) {
        if (dateTime == null) {
            return null;
        }
        if (pattern == null || pattern.isEmpty()) {
            pattern = YYYYMMDDHHMMSSS_PATTERN;
        }
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern(pattern);
        return dateTime.format(formatter);
    }

}