Technology Sharing

한어Русский языкEnglishFrançaisIndonesianSanskrit日本語DeutschPortuguêsΕλληνικάespañolItalianoSuomalainenLatina

1. Improved Background

Java 8 has made comprehensive improvements to time processing, redesigning all date, time, calendar, and time zone related APIs, and placing them all in the java.time package and subpackages.

Java 5 shortcomings：

1. Not thread safe：java.util.Date It is not thread-safe, and you must handle multi-threaded concurrency issues yourself when using this class.
2. Poor design : Dates and date formatting are spread across multiple packages.java.util.Date The default date is from1900Start, the month from 1 Start from 0 In the beginning, there was no unity. And Date The class also lacks methods for directly manipulating dates.
3. Difficulty handling time zones: Due to poor design, you have to write a lot of code to handle time zone issues.

Java 8 Improvements：

1. Thread Safety: New date and timeAPIIs thread-safe not onlysettermethod, and any changes to the instance will return a new instance while ensuring that the original instance remains unchanged.
2. Date Modified: The new date and time API provides a large number of methods for modifying various parts of the date and time and returning a new instance.
3. area: In terms of time zones, the new date and time API introduces the concept of domains.
4. Combination and Splitting: The original complex API was reorganized and split into several classes.

2. Local date and time

1. LocalDate: Used to represent a date without a time zone, for example: 2024-07-06.

   import java.time.LocalDate;
   import java.time.Month;
   
   public class LocalDateExample {
       public static void main(String[] args) {
           // 获取当前日期
           LocalDate today = LocalDate.now();
           System.out.println("当前日期: "   today);
   
           // 创建指定日期
           LocalDate specificDate = LocalDate.of(2024, Month.JULY, 6);
           System.out.println("指定日期: "   specificDate);
   
           // 日期操作示例
           LocalDate tomorrow = today.plusDays(1);
           System.out.println("明天的日期: "   tomorrow);
       }
   }
   
   // 输出
   当前日期: 2024-07-06
   指定日期: 2024-07-06
   明天的日期: 2024-07-07
   
                       上一篇
                       下一篇