LocalDate类中的常用方法
public class DemoLocalDate {
public static void main(String[] args) {
// 当前日期:2019-10-16
LocalDate today = LocalDate.now();
// 获取localDate对象
LocalDate date2 = LocalDate.of(2019, 10, 1);
LocalDate date3 = LocalDate.parse("2019-9-10");
// 当前日期年份:2019
System.out.println(today.getYear());
// 当前日期月份对象:OCTOBER
System.out.println(today.getMonth());
// 当前日期月份:10
System.out.println(today.getMonthValue());
// 该日期是当前周的第几天:3
System.out.println(today.getDayOfWeek().getValue());
// 该日期是当前月的第几天:16
System.out.println(today.getDayOfMonth());
// 该日期是当前年的第几天:289
System.out.println(today.getDayOfYear());
// 修改该日期的年份:2022-10-16
System.out.println(today.withYear(2022));
// 修改该日期的月份:2019-12-16
System.out.println(today.withMonth(12));
// 修改该日期在当月的天数:2019-10-01
System.out.println(today.withDayOfMonth(1));
// 判断是否是闰年:false
System.out.println(today.isLeapYear());
// 当前年份有多少天:365
System.out.println(today.lengthOfYear());
// 当前月份有多少天:31
System.out.println(today.lengthOfMonth());
// 比较该日期与other日期的大小,返回正数,那么当前对象时间较晚(数字较大):15
int i = today.compareTo(LocalDate.of(2019, 10, 1));
System.out.println(i);
// 比较该日期是否比参数日期早(true为早):true
System.out.println(today.isBefore(LocalDate.of(2019,10,18)));
// 比较该日期是否比参数日期晚(true为晚):false
System.out.println(today.isAfter(LocalDate.of(2019,10,18)));
// 比较两个日期是否相等:true
System.out.println(today.isEqual(LocalDate.now()));
// 当前日期增加指定的年数:2020-10-16
System.out.println(today.plusYears(1));
// 当前日期增加指定的月份:2019-12-16
System.out.println(today.plusMonths(2));
// 当前日期增加指定的周数:2019-10-30
System.out.println(today.plusWeeks(2));
// 当前日期增加指定的天数:2019-10-23
System.out.println(today.plusDays(7));
// 当前日期减少指定的年数:2018-10-16
System.out.println(today.minusYears(1));
// 当前日期减少指定的月份:2019-06-16
System.out.println(today.minusMonths(4));
// 当前日期减少指定的周数:2019-10-09
System.out.println(today.minusWeeks(1));
// 当前日期减少指定的天数:2019-10-01
System.out.println(today.minusDays(15));
// LocalDate 转 String
DateTimeFormatter dateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");
String dateString = today.format(dateTimeFormatter);
// String 转 LocalDate
String str = "2010-10-01";
DateTimeFormatter fmt = DateTimeFormatter.ofPattern("yyyy-MM-dd");
LocalDate date = LocalDate.parse(str, fmt);
// Date 转 LocalDate
Date now = new Date();
// 先将转换为ZonedDateTime
Instant instant = now.toInstant();
ZoneId zoneId = ZoneId.systemDefault();
ZonedDateTime zonedDateTime = instant.atZone(zoneId);
// 使用它的toLocalDate()方法从ZonedDateTime获取LocalDate。
LocalDate localDate = zonedDateTime.toLocalDate();
// Wed Oct 16 15:26:41 CST 2019
System.out.println(now);
// 2019-10-16
System.out.println(localDate);
// LocalDate 转 Date
ZoneId id = ZoneId.systemDefault();
LocalDate now1 = LocalDate.now();
ZonedDateTime dateTime = now1.atStartOfDay(id);
Date date1 = Date.from(dateTime.toInstant());
System.out.println(date1);
}
}