Java8 LocalDateTime的补充工具方法
import java.time.*;
import java.time.format.DateTimeFormatter;
import java.time.format.DateTimeFormatterBuilder;
import java.time.temporal.ChronoField;
import java.util.Date;
public class LocalDateTimeUtil {
public static final String YYYY = "yyyy";
public static final String YYYYMM = "yyyyMM";
public static final String YYYYMMDD = "yyyyMMdd";
public static final String YYYYMMDDHH = "yyyyMMddHH";
public static final String YYYYMMDDHHMM = "yyyyMMddHHmm";
public static final String YYYYMMDDHHMMSS = "yyyyMMddHHmmss";
public static final String YYYY_MM = "yyyy-MM";
public static final String YYYY_MM_DD = "yyyy-MM-dd";
public static final String YYYY_MM_DD_HH = "yyyy-MM-dd HH";
public static final String YYYY_MM_DD_HH_MM = "yyyy-MM-dd HH:mm";
public static final String YYYY_MM_DD_HH_MM_SS = "yyyy-MM-dd HH:mm:ss";
private static final String BASE_TIME_FORMAT = "[yyyyMMddHHmmss][yyyyMMddHHmm][yyyyMMddHH][yyyyMMdd][yyyyMM][yyyy][[-][/][.]MM][[-][/][.]dd][ ][HH][[:][.]mm][[:][.]ss][[:][.]SSS]";
public static void main(String[] args) {
// 测试链式调用
System.out.println(builder.parse("2019-09-25").atStartOfMonth().plusHours(1).toDate());
// 测试format
System.out.println(format(LocalDateTime.now(), YYYY_MM_DD_HH_MM_SS));
// 测试解析时间
System.out.println(parse("2019"));
System.out.println(parse("201907"));
System.out.println(parse("20190726"));
System.out.println(parse("2019072615"));
System.out.println(parse("201907261546"));
System.out.println(parse("20190726154628"));
System.out.println(parse("2019-07"));
System.out.println(parse("2019-07-26"));
System.out.println(parse("2019-07-26 15"));
System.out.println(parse("2019-07-26 15:47"));
System.out.println(parse("2019-07-26 15:47:26"));
System.out.println(parse("2019-07-26 15:47:26:156"));
System.out.println(parse("2019/07"));
System.out.println(parse("2019/07/26"));
System.out.println(parse("2019/07/26 15"));
System.out.println(parse("2019/07/26 15:47"));
System.out.println(parse("2019/07/26 15:47:58"));
System.out.println(parse("2019/07/26 15:47:58:147"));
System.out.println(parse("2019.07"));
System.out.println(parse("2019.07.26"));
System.out.println(parse("2019.07.26 15"));
System.out.println(parse("2019.07.26 15.48"));
System.out.println(parse("2019.07.26 15.48.49"));
System.out.println(parse("2019.07.26 15.48.49.123"));
System.out.println(parse("07-26"));
System.out.println(parse("07-26 15:49:12"));
// 测试传入自定义时间格式
System.out.println(parseByPattern("26-07-2019", "dd-MM-yyyy"));
// 测试获取开始时间的方法
LocalDateTime time = LocalDateTime.now();
System.out.println(atStartOfSecond(time));
System.out.println(atStartOfMinute(time));
System.out.println(atStartOfHour(time));
System.out.println(atStartOfDay(time));
System.out.println(atStartOfWeek(time));
System.out.println(atStartOfMonth(time));
System.out.println(atStartOfYear(time));
// 测试获取时间间隔的方法
System.out.println(formatDuration(LocalDateTime.of(2018, 6, 25, 15, 0, 0), time));
// 测试来回转换
System.out.println(toDate(time));
System.out.println(fromDate(new Date()));
System.out.println(toInstant(time));
System.out.println(fromInstant(Instant.now()));
System.out.println(toTimestamp(time));
System.out.println(fromTimestamp(Instant.now().toEpochMilli()));
}
/**
* 根据pattern格式化时间
*
* @param localDateTime localDateTime
* @param pattern pattern
* @return String
*/
public static String format(LocalDateTime localDateTime, String pattern) {
return localDateTime.format(DateTimeFormatter.ofPattern(pattern));
}
/**
* 【推荐】解析常用时间字符串，支持,并不局限于以下形式：
* [yyyy][yyyy-MM][yyyy-MM-dd][yyyy-MM-dd HH][yyyy-MM-dd HH:mm][yyyy-MM-dd HH:mm:ss][yyyy-MM-dd HH:mm:ss:SSS]
* [yyyy][yyyy/MM][yyyy/MM/dd][yyyy/MM/dd HH][yyyy/MM/dd HH:mm][yyyy/MM/dd HH:mm:ss][yyyy/MM/dd HH:mm:ss:SSS]
* [yyyy][yyyy.MM][yyyy.MM.dd][yyyy.MM.dd HH][yyyy.MM.dd HH.mm][yyyy.MM.dd HH.mm.ss][yyyy.MM.dd HH.mm.ss.SSS]
* [yyyy][yyyyMM][yyyyMMdd][yyyyMMddHH][yyyyMMddHHmm][yyyyMMddHHmmss]
* [MM-dd]
* 不支持yyyyMMddHHmmssSSS，因为本身DateTimeFormatter.ofPattern("yyyyMMddHHmmssSSS")就不支持这个形式
*
* @param timeString timeString
* @return LocalDateTime
*/
public static LocalDateTime parse(String timeString) {
return LocalDateTime.parse(timeString, getDateTimeFormatterByPattern(BASE_TIME_FORMAT));
}
/**
* 根据传进来的pattern返回LocalDateTime，自动补齐
*
* @param timeString timeString
* @param pattern pattern
* @return LocalDateTime
*/
public static LocalDateTime parseByPattern(String timeString, String pattern) {
return LocalDateTime.parse(timeString, getDateTimeFormatterByPattern(pattern));
}
/**
* 自由解析时间的基础
*
* @param pattern pattern
* @return DateTimeFormatter
*/
private static DateTimeFormatter getDateTimeFormatterByPattern(String pattern) {
return new DateTimeFormatterBuilder()
.appendPattern(pattern)
.parseDefaulting(ChronoField.YEAR_OF_ERA, LocalDateTime.now().getYear())
.parseDefaulting(ChronoField.MONTH_OF_YEAR, 1)
.parseDefaulting(ChronoField.DAY_OF_MONTH, 1)
.parseDefaulting(ChronoField.HOUR_OF_DAY, 0)
.parseDefaulting(ChronoField.MINUTE_OF_HOUR, 0)
.parseDefaulting(ChronoField.SECOND_OF_MINUTE, 0)
.parseDefaulting(ChronoField.NANO_OF_SECOND, 0)
.toFormatter();
}
public static LocalDate toLocalDate(LocalDateTime localDateTime) {
return localDateTime.toLocalDate();
}
public static LocalDateTime fromLocalDate(LocalDate localDate) {
return localDate.atStartOfDay();
}
public static Date toDate(LocalDateTime localDateTime) {
return Date.from(localDateTime.atZone(ZoneId.systemDefault()).toInstant());
}
public static LocalDateTime fromDate(Date date) {
return date.toInstant().atZone(ZoneId.systemDefault()).toLocalDateTime();
}
public static long toTimestamp(LocalDateTime localDateTime) {
return toInstant(localDateTime).toEpochMilli();
}
public static LocalDateTime fromTimestamp(long timestamp) {
return fromInstant(Instant.ofEpochMilli(timestamp));
}
public static Instant toInstant(LocalDateTime localDateTime) {
return localDateTime.atZone(ZoneId.systemDefault()).toInstant();
}
public static LocalDateTime fromInstant(Instant instant) {
return instant.atZone(ZoneId.systemDefault()).toLocalDateTime();
}
public static LocalDateTime atStartOfSecond(LocalDateTime localDateTime) {
return localDateTime.withNano(0);
}
public static LocalDateTime atStartOfMinute(LocalDateTime localDateTime) {
return atStartOfSecond(localDateTime).withSecond(0);
}
public static LocalDateTime atStartOfHour(LocalDateTime localDateTime) {
return atStartOfMinute(localDateTime).withMinute(0);
}
public static LocalDateTime atStartOfDay(LocalDateTime localDateTime) {
return atStartOfHour(localDateTime).withHour(0);
}
public static LocalDateTime atStartOfWeek(LocalDateTime localDateTime) {
return atStartOfDay(localDateTime).minusDays(localDateTime.getDayOfWeek().getValue() - 1);
}
public static LocalDateTime atStartOfMonth(LocalDateTime localDateTime) {
return atStartOfDay(localDateTime).withDayOfMonth(1);
}
public static LocalDateTime atStartOfYear(LocalDateTime localDateTime) {
return atStartOfMonth(localDateTime).withMonth(1);
}
/**
* 获得形如：XXX 天 XXX 小时 XXX 分 XXX 秒 XXX 毫秒 的格式化后的时间间隔
* 如只想获得统一单位的时间间隔，请直接用 Duration
*
* @param startTime 开始时间
* @param endTime 结束时间
* @return String
*/
public static String formatDuration(LocalDateTime startTime, LocalDateTime endTime) {
if (startTime.compareTo(endTime) > 0) {
return "出错啦 ! 起始时间大于结束时间";
}
Duration duration = Duration.between(startTime, endTime);
StringBuilder output = new StringBuilder();
long day = duration.toDays();
if (day > 0) {
output.append(day).append(" 天 ");
duration = duration.minusDays(day);
}
long hour = duration.toHours();
if (hour > 0) {
output.append(hour).append(" 小时 ");
duration = duration.minusHours(hour);
}
long minute = duration.toMinutes();
if (minute > 0) {
output.append(minute).append(" 分 ");
duration = duration.minusMinutes(minute);
}
long second = duration.getSeconds();
if (second > 0) {
output.append(second).append(" 秒 ");
duration = duration.minusSeconds(second);
}
output.append(duration.toMillis()).append(" 毫秒");
return output.toString();
}
public static class builder {
private LocalDateTime builderTime;
public builder() {
builderTime = LocalDateTime.now();
}
public builder(LocalDateTime localDateTime) {
builderTime = localDateTime;
}
public static builder now() {
return new builder();
}
public static builder parse(String timeString) {
return new builder(LocalDateTime.parse(timeString, LocalDateTimeUtil.getDateTimeFormatterByPattern(BASE_TIME_FORMAT)));
}
public static builder parseByPattern(String timeString, String pattern) {
return new builder(LocalDateTime.parse(timeString, LocalDateTimeUtil.getDateTimeFormatterByPattern(pattern)));
}
public static builder fromLocalDate(LocalDate localDate) {
return new builder(localDate.atStartOfDay());
}
public static builder fromDate(Date date) {
return new builder(date.toInstant().atZone(ZoneId.systemDefault()).toLocalDateTime());
}
public static builder fromTimestamp(long timestamp) {
return new builder(LocalDateTimeUtil.fromInstant(Instant.ofEpochMilli(timestamp)));
}
public static builder fromInstant(Instant instant) {
return new builder(instant.atZone(ZoneId.systemDefault()).toLocalDateTime());
}
public builder withYear(int year) {
builderTime = builderTime.withYear(year);
return this;
}
public builder withMonth(int month) {
builderTime = builderTime.withMonth(month);
return this;
}
public builder withDayOfMonth(int dayOfMonth) {
builderTime = builderTime.withDayOfMonth(dayOfMonth);
return this;
}
public builder withDayOfYear(int dayOfYear) {
builderTime = builderTime.withDayOfYear(dayOfYear);
return this;
}
public builder withHour(int hour) {
builderTime = builderTime.withHour(hour);
return this;
}
public builder withMinute(int minute) {
builderTime = builderTime.withMinute(minute);
return this;
}
public builder withSecond(int second) {
builderTime = builderTime.withSecond(second);
return this;
}
public builder withNano(int nanoOfSecond) {
builderTime = builderTime.withNano(nanoOfSecond);
return this;
}
public builder plusYears(long years) {
builderTime = builderTime.plusYears(years);
return this;
}
public builder plusMonths(long months) {
builderTime = builderTime.plusMonths(months);
return this;
}
public builder plusWeeks(long weeks) {
builderTime = builderTime.plusWeeks(weeks);
return this;
}
public builder plusDays(long days) {
builderTime = builderTime.plusDays(days);
return this;
}
public builder plusHours(long hours) {
builderTime = builderTime.plusHours(hours);
return this;
}
public builder plusMinutes(long minutes) {
builderTime = builderTime.plusMinutes(minutes);
return this;
}
public builder plusSeconds(long seconds) {
builderTime = builderTime.plusSeconds(seconds);
return this;
}
public builder plusNanos(long nanos) {
builderTime = builderTime.plusNanos(nanos);
return this;
}
public builder minusYears(long years) {
builderTime = builderTime.minusYears(years);
return this;
}
public builder minusMonths(long months) {
builderTime = builderTime.minusMonths(months);
return this;
}
public builder minusWeeks(long weeks) {
builderTime = builderTime.minusWeeks(weeks);
return this;
}
public builder minusDays(long days) {
builderTime = builderTime.minusDays(days);
return this;
}
public builder minusHours(long hours) {
builderTime = builderTime.minusHours(hours);
return this;
}
public builder minusMinutes(long minutes) {
builderTime = builderTime.minusMinutes(minutes);
return this;
}
public builder minusSeconds(long seconds) {
builderTime = builderTime.minusSeconds(seconds);
return this;
}
public builder minusNanos(long nanos) {
builderTime = builderTime.minusNanos(nanos);
return this;
}
public builder atStartOfSecond() {
builderTime = builderTime.withNano(0);
return this;
}
public builder atStartOfMinute() {
atStartOfSecond();
builderTime = builderTime.withSecond(0);
return this;
}
public builder atStartOfHour() {
atStartOfMinute();
builderTime = builderTime.withMinute(0);
return this;
}
public builder atStartOfDay() {
atStartOfHour();
builderTime = builderTime.withHour(0);
return this;
}
public builder atStartOfWeek() {
atStartOfDay();
builderTime = builderTime.minusDays(builderTime.getDayOfWeek().getValue() - 1);
return this;
}
public builder atStartOfMonth() {
atStartOfDay();
builderTime = builderTime.withDayOfMonth(1);
return this;
}
public builder atStartOfYear(LocalDateTime localDateTime) {
atStartOfDay();
builderTime = builderTime.withMonth(1);
return this;
}
public String format(String pattern) {
return LocalDateTimeUtil.format(builderTime, pattern);
}
public LocalDate toLocalDate() {
return builderTime.toLocalDate();
}
public Date toDate() {
return Date.from(builderTime.atZone(ZoneId.systemDefault()).toInstant());
}
public long toTimestamp() {
return toInstant().toEpochMilli();
}
public Instant toInstant() {
return builderTime.atZone(ZoneId.systemDefault()).toInstant();
}
public LocalDateTime build() {
return builderTime;
}
}
}
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