LocalTime 时java8 中用于表示时间的类.

package org.zongf.learn.java8.date;

import org.junit.Test;

import java.time.Duration;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.format.DateTimeFormatter;
import java.time.temporal.ChronoField;
import java.time.temporal.ChronoUnit;

/** * @Description: 测试LocalTime 类 * @author: zongf * @date: 2018-06-29 15:22 */
public class TestLocalTime {

    // 构造方法
    @Test
    public void test_constructor(){

        // 获取当前时间,默认格式: HH:mm:ss.SSS
        System.out.println(LocalTime.now());

        // 通过时分创建时间
        System.out.println(LocalTime.of(10, 30));

        // 通过时分秒创建时间
        System.out.println(LocalTime.of(10, 30, 50));

        // 通过时分秒毫秒创建时间
        System.out.println(LocalTime.of(10, 30, 50, 459));

        // 获取当天第1000 秒的时间
        System.out.println(LocalTime.ofSecondOfDay(1000));

        // 获取当天第 1000 纳秒的时间
        System.out.println(LocalTime.ofNanoOfDay(1000000000));

        // 通过字符串解析时间
        System.out.println(LocalTime.parse("10:30"));
        System.out.println(LocalTime.parse("10:30:50"));
        System.out.println(LocalTime.parse("10:30:50.361"));

        // 通过自定义格式解析时间
        System.out.println(LocalTime.parse("10:30:50.459", DateTimeFormatter.ofPattern("HH:mm:ss.SSS")));

    }

    // 测试get 方法
    @Test
    public void test_get(){

        LocalTime now = LocalTime.now();

        System.out.println("当前时间:" + now);
        System.out.println("时:" + now.getHour());
        System.out.println("分:" + now.getMinute());
        System.out.println("秒:" + now.getSecond());
        System.out.println("毫秒:" + now.getNano());
        System.out.println("当天第几秒:" + now.toSecondOfDay());
        System.out.println("当天第几毫秒:" + now.toNanoOfDay());

        System.out.println("时:" + now.get(ChronoField.HOUR_OF_DAY));
        System.out.println("分:" + now.get(ChronoField.MINUTE_OF_HOUR));
        System.out.println("秒:" + now.get(ChronoField.SECOND_OF_MINUTE));
        System.out.println("毫秒:" + now.get(ChronoField.MILLI_OF_SECOND));
        System.out.println("微妙:" + now.getLong(ChronoField.MICRO_OF_SECOND));
        System.out.println("纳秒:" + now.get(ChronoField.NANO_OF_SECOND));
        System.out.println("当天第几分钟:" + now.get(ChronoField.MINUTE_OF_DAY));
        System.out.println("当天第几秒:" + now.get(ChronoField.SECOND_OF_DAY));
        System.out.println("当天第几毫秒:" + now.get(ChronoField.MILLI_OF_DAY));
        System.out.println("当天第几微妙:" + now.getLong(ChronoField.MICRO_OF_DAY));
        System.out.println("当天第几纳秒:" + now.getLong(ChronoField.NANO_OF_DAY));
        System.out.println("12小时制,取值范围[0,11],时:" + now.get(ChronoField.HOUR_OF_AMPM));
        System.out.println("12小时制,取值范围[1,12],时:" + now.get(ChronoField.CLOCK_HOUR_OF_AMPM));
        System.out.println("24小时制,取值范围[1,24],时:" + now.get(ChronoField.CLOCK_HOUR_OF_DAY));
    }

    // 测试时间运算方法
    @Test
    public void test_plus(){
        LocalTime lt = LocalTime.of(13,30,40, 100_000_000);

        System.out.println("当前时间:" + lt);
        System.out.println();

        System.out.println("3小时后:" + lt.plusHours(3));
        System.out.println("20分钟后:" + lt.plusMinutes(20));
        System.out.println("10秒后:" + lt.plusSeconds(10));
        System.out.println("2_000_000纳秒后:" + lt.plusNanos(2_000_000));
        System.out.println("3小时前:" + lt.minusHours(3));
        System.out.println("20分钟前:" + lt.minusMinutes(20));
        System.out.println("10秒钟前:" + lt.minusSeconds(10));
        System.out.println("2_000_000秒钟前:" + lt.minusNanos(2_000_000));
        System.out.println();

        System.out.println("3小时后:" + lt.plus(Duration.ofHours(3)));
        System.out.println("20分钟后:" + lt.plus(Duration.ofMinutes(20)));
        System.out.println("10秒钟后:" + lt.plus(Duration.ofSeconds(10)));
        System.out.println("2000毫秒后:" + lt.plus(Duration.ofMillis(200)));
        System.out.println("2_000_000纳秒后:" + lt.plus(Duration.ofNanos(2_000_000)));
        System.out.println();

        System.out.println("3小时前:" + lt.minus(Duration.ofHours(3)));
        System.out.println("20分钟前:" + lt.minus(Duration.ofMinutes(20)));
        System.out.println("10秒钟前:" + lt.minus(Duration.ofSeconds(10)));
        System.out.println("2000毫秒前:" + lt.minus(Duration.ofMillis(200)));
        System.out.println("2_000_000纳秒前:" + lt.minus(Duration.ofNanos(2_000_000)));
        System.out.println();

    }

    // 测试比较方法
    @Test
    public void compare(){

        LocalTime lt1 = LocalTime.of(10, 30, 50, 100_000_000);
        LocalTime lt2 = LocalTime.of(16, 20, 30, 200_000_000);

        System.out.println(lt1.isBefore(lt2));
        System.out.println(lt1.isAfter(lt2));
        System.out.println(lt1.compareTo(lt2));
        System.out.println(lt2.compareTo(lt1));
    }

    // 测试修改方法
    @Test
    public void with(){
        LocalTime lt = LocalTime.of(10, 30, 50, 100_000_000);

        System.out.println(lt);
        System.out.println("替换小时为15: " + lt.withHour(15));
        System.out.println("替换分钟为35: " + lt.withMinute(35));
        System.out.println("替换秒为55: " + lt.withSecond(55));
        System.out.println("替换纳秒为300_000_000: " + lt.withNano(300_000_000));

    }

    // 测试时间间隔方法
    @Test
    public void test_until(){
        // 计算两个时间之间的差
        LocalTime ldt1 = LocalTime.of(18, 10, 20, 100_000);
        LocalTime ldt2 = LocalTime.of(8, 30, 40, 200_000);

        System.out.println("时间间隔-总小时数:" + ldt1.until(ldt2, ChronoUnit.HOURS));
        System.out.println("时间间隔-总分钟数:" + ldt1.until(ldt2, ChronoUnit.MINUTES));
        System.out.println("时间间隔-总秒数:" + ldt1.until(ldt2, ChronoUnit.SECONDS));
        System.out.println("时间间隔-总毫秒数:" + ldt1.until(ldt2, ChronoUnit.MILLIS));
        System.out.println("时间间隔-总微秒数:" + ldt1.until(ldt2, ChronoUnit.MICROS));
        System.out.println("时间间隔-总纳秒数:" + ldt1.until(ldt2, ChronoUnit.NANOS));
        System.out.println("时间间隔-总半天数(多少个12小时):" + ldt1.until(ldt2, ChronoUnit.HALF_DAYS));
    }

    // 计算时间间隔
    @Test
    public void test_between(){

        LocalTime lt1 = LocalTime.of(12, 30, 50, 100_000_000);
        LocalTime lt2 = LocalTime.of(15, 50, 30, 200_000_000);

        Duration duration = Duration.between(lt1, lt2);
        System.out.println("时间间隔-总小时数:" + duration.toHours());
        System.out.println("时间间隔-总分钟数:" + duration.toMinutes());
        System.out.println("时间间隔-总秒数:" + duration.toMillis());
        System.out.println("时间间隔-总毫秒数:" + duration.toNanos());
        System.out.println("时间间隔-总纳秒数:" + duration.toString());

        System.out.println("日期间隔是否是负数:" + duration.isNegative());
        System.out.println("日期间隔是否是0:" + duration.isZero());

    }

    // 测试转换为LocalDateTime 方法
    @Test
    public void test_converter(){

        LocalTime lt = LocalTime.now();

        LocalDateTime ldt = lt.atDate(LocalDate.now());
        System.out.println(ldt);

    }

}