JAva 8 LocalDateとLocalDateTime時間クラスの簡単な応用


くだらないことは言わないで、直接コードの実例を貼ります
@Test
	public void testTime() {
		//       
		LocalDate now = LocalDate.now();
		System.out.println(now);//  :2018-09-13
		
		//    ,  4     
		LocalDate withMonth = LocalDate.now().withMonth(4);
		System.out.println(withMonth);//2018-04-13
		//    
		LocalDate withYear = LocalDate.now().withYear(2017);
		System.out.println(withYear);//2017-09-13
		
		//        
		LocalDate withDayOfMonth = LocalDate.now().withDayOfMonth(30);
		System.out.println(withDayOfMonth);//2017-09-30
		
		//        
		LocalDate withDayOfMonth2 = LocalDate.now().withMonth(10).withDayOfMonth(1);
		System.out.println(withDayOfMonth2);//2018-10-01
		
		//         
		LocalDate withDayOfMonth3 = LocalDate.now().withMonth(10);
		int lengthOfMonth = withDayOfMonth3.lengthOfMonth();
		LocalDate withDayOfMonth4 = withDayOfMonth3.withDayOfMonth(lengthOfMonth);
		System.out.println(withDayOfMonth4);//2018-10-31
		
		//     
		String format = LocalDate.now().format(DateTimeFormatter.ofPattern("yyyy MM "));
		System.out.println(format);//2018 09 
		
		//       
		LocalDate plusMonths = LocalDate.now().plusMonths(2);
		System.out.println(plusMonths);//2018-11-13
		
		//   
		LocalDate plusYears = LocalDate.now().plusYears(5);
		System.out.println(plusYears);//2023-09-13
		
		
		
		//       
		LocalDateTime atStartOfDay = LocalDateTime.now();
		System.out.println(atStartOfDay);//  :2018-09-13T15:33:32.653
		
		/*
		 * LocalDateTime   LocalDate         ,        ,             
             
		 */
		
	}

LocalDateTimeはLocalDateの多くの方法とほぼ一致しています.ここでは一つ一つプレゼンテーションをしません.興味のある友达は自分で探求することができます.