jdk8_dateApi

Posted 2022-12-03 sico

package com.zhangwl.pg0924;

import org.junit.Test;

import javax.swing.text.DateFormatter;
import java.text.DateFormat;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.Month;
import java.time.format.DateTimeFormatter;

/**
 * @ClassName DateApiDemo
 * @Description
 * @Author zhangwl
 * @Date 2019/9/24 22:43
 * @Version 1.0
 **/
public class DateApiDemo 

    /*日期*/
    @Test
    public void test_local_date() 
        LocalDate nowDate = LocalDate.now();
        System.out.println("今天的日期：" + nowDate);
        int year = nowDate.getYear();
        System.out.println("年：" + year);
        int month = nowDate.getMonthValue();
        System.out.println("月：" + month);
        int day = nowDate.getDayOfMonth();
        System.out.println("日：" + day);
    

    /*时间*/
    @Test
    public void test_local_time() 
        LocalTime nowTime = LocalTime.now();
        System.out.println("现在的时间：" + nowTime);
        int hour = nowTime.getHour();
        System.out.println("时：" + hour);
        int minute = nowTime.getMinute();
        System.out.println("分：" + minute);
        int second = nowTime.getSecond();
        System.out.println("秒：" + second);
        int nano = nowTime.getNano();
        System.out.println("毫秒：" + nano);
    

    /*日期时间*/
    @Test
    public void test_local_date_time() 
        LocalDateTime nowDateTime = LocalDateTime.now();
        System.out.println("今天日期时间：" + nowDateTime);
        System.out.println("年：" + nowDateTime.getYear());
        System.out.println("月：" + nowDateTime.getMonthValue());
        System.out.println("日：" + nowDateTime.getDayOfMonth());
        System.out.println("**********************************");
        System.out.println("时：" + nowDateTime.getHour());
        System.out.println("分：" + nowDateTime.getMinute());
        System.out.println("秒：" + nowDateTime.getSecond());
        System.out.println("毫秒：" + nowDateTime.getNano());
    

    /*获取指定日期的日期*/
    @Test
    public void test_cust_local_date() 
        LocalDate localDate = LocalDate.of(1991, 10, 12);
        System.out.println(LocalDate.ofYearDay(1991, localDate.getDayOfYear()));
        System.out.println(LocalDate.ofEpochDay(localDate.toEpochDay()));//参数为距离1970-01-01的天数
        System.out.println("*******************************************");
        System.out.println(LocalDate.parse("1991-10-12"));
        System.out.println(LocalDate.parse("19911012", DateTimeFormatter.ofPattern("yyyyMMdd")));
    

    @Test
    public void test_cust_local_time() 
        System.out.println(LocalTime.of(8, 20));
        System.out.println(LocalTime.of(8, 20, 30));
        System.out.println(LocalTime.of(8, 20, 30, 40));
        System.out.println("*************************************************************");
        LocalTime tTime = LocalTime.of(8, 20, 30, 40);
        System.out.println(LocalTime.ofSecondOfDay(tTime.toSecondOfDay()));//参数为距离当天零时的秒数
        System.out.println(LocalTime.ofNanoOfDay(tTime.toNanoOfDay()));
        System.out.println("*************************************************************");
        System.out.println(LocalTime.parse("08:20:30"));
        System.out.println(LocalTime.parse("082030", DateTimeFormatter.ofPattern("HHmmss")));
    

    @Test
    public void test_cust_local_date_time() 
        System.out.println(LocalDateTime.of(1991, 10, 12, 8, 20, 30));
        System.out.println(LocalDateTime.of(1991, Month.OCTOBER, 8, 20, 30, 150));
        System.out.println(LocalDateTime.parse("1991-10-12 08:20:30", DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
    

    /*日期的比较*/
    @Test
    public void test_comp_local_date() 
        LocalDate myDate = LocalDate.of(1991, 10, 12);
        LocalDate nowDate = LocalDate.now();
        /*比较两个日期*/
        System.out.println("今天是1991-10-12吗?" + nowDate.equals(myDate));