Calendar.before(Object when),为什么是Object?

Calendar.before(Object when), why Object?(Calendar.before(Object when),为什么是Object?)
本文介绍了Calendar.before(Object when),为什么是Object?的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着跟版网的小编来一起学习吧!

问题描述

来自Calendar.before(Object when)的javadoc:

From the javadoc of Calendar.before(Object when):

返回此日历是否表示指定对象表示的时间之前的时间.该方法等价于:

Returns whether this Calendar represents a time before the time represented by the specified Object. This method is equivalent to:

compareTo(when) < 0

当且仅当 when 是 Calendar 实例.否则,该方法返回 false.

if and only if when is a Calendar instance. Otherwise, the method returns false.

如果当有人传递不是 Calendar 实例的东西时它返回 false,为什么它会接受 Object?为什么不直接接受 Calendar 实例?这让我在很长一段时间内一直在关注某个功能中的不正确结果.

Why does it accepts an Object if when someone passes something that's not a Calendar instance it returns false? Why not just accepting a Calendar instance? This kept me watching for uncorrect results in a functionality for quite some time.

推荐答案

我认为没有什么特别的原因.java.util.Calendar 有一些设计问题,我们不得不忍受,很遗憾.

I think there is no particular reason for that. java.util.Calendar has some design issues we have have to live with, unfortunately.

这篇关于Calendar.before(Object when),为什么是Object?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持跟版网!

本站部分内容来源互联网,如果有图片或者内容侵犯了您的权益,请联系我们,我们会在确认后第一时间进行删除!

相关文档推荐

Month is not printed from a date - Java DateFormat(月份不是从日期打印的 - Java DateFormat)
java get week of year for given a date(java获取给定日期的一年中的一周)
Get the number of days, weeks, and months, since Epoch in Java(获取自 Java 中的 Epoch 以来的天数、周数和月数)
Is there a good way to get the date of the coming Wednesday?(有什么好方法可以得到即将到来的星期三的日期吗?)
Calendar view for Android GingerBread and before (APIlt;11)(Android GingerBread 及之前的日历视图 (API11))
How to save and retrieve Date in SharedPreferences(如何在 SharedPreferences 中保存和检索日期)