zoukankan      html  css  js  c++  java
  • java 获取当前系统时间

    Java的Date获取时间函数都是deprecated 

    可以使用:

    https://stackoverflow.com/questions/5175728/how-to-get-the-current-date-time-in-java

    所说方法

    It depends on what form of date / time you want:

    • If you want the date / time as a single numeric value, then System.currentTimeMillis() gives you that, expressed as the number of milliseconds after the UNIX epoch (as a Java long). This value is a delta from a UTC time-point, and is independent of the local time-zone ... assuming that the system clock has been set correctly.

    • If you want the date / time in a form that allows you to access the components (year, month, etc) numerically, you could use one of the following:

      • new Date() gives you a Date object initialized with the current date / time. The problem is that the Date API methods are mostly flawed ... and deprecated.

      • Calendar.getInstance() gives you a Calendar object initialized with the current date / time, using the default Locale and TimeZone. Other overloads allow you to use a specific Locale and/or TimeZone. Calendar works ... but the APIs are still cumbersome.

      • new org.joda.time.DateTime() gives you a Joda-time object initialized with the current date / time, using the default time zone and chronology. There are lots of other Joda alternatives ... too many to describe here.

      • in Java 8, calling LocalDateTime.now() and ZonedDateTime.now() will give you representations for the current date / time.

    Prior to Java 8, most people who know about these things recommended Joda-time as having (by far) the best Java APIs for doing things involving time point and duration calculations. With Java 8, this is no longer true. However, if you are already using Joda time in your codebase, there is no strong reason to migrate.

    date和datetime转换

    https://stackoverflow.com/questions/19431234/converting-between-java-time-localdatetime-and-java-util-date

    Date in = new Date();
    LocalDateTime ldt = LocalDateTime.ofInstant(in.toInstant(), ZoneId.systemDefault());
    Date out = Date.from(ldt.atZone(ZoneId.systemDefault()).toInstant());
    

     

  • 相关阅读:
    docker
    iOS开发之抓取花瓣网json数据
    iOS与Android工程项目的简单对比
    Android与iOS的比较
    Jenkins时间和centos时间相差八小时解决方法
    MYSQL中索引里面的基数是什么意思
    使用Java写一个minio的客户端上传下载文件
    Java 使用AOP实现打印日志
    macOS使用brew安装mysql8.x
    MacOS安装homebrew报错:curl: (7) Failed to connect to raw.githubusercontent.com port 443: Connection refused
  • 原文地址:https://www.cnblogs.com/hong2016/p/7447220.html
Copyright © 2011-2022 走看看