Java optional工具类的相关内容

JAVA8实战 - Optional工具类

JAVA8实战 - Optional工具类前言没错，这又是一个新的专栏，JAVA8可以说是JAVA划时代的一个版本，几乎是让JAVA焕发了第三春（第二春在JDK5），当然里面的新特性也是十分重要的，虽然Java现在都已经到了10几的版本，但是国内多数使用的版本还是JAVA8，所以这个系列将会围绕J...

JAVA8实战 - Optional工具类

前言没错，这又是一个新的专栏，JAVA8可以说是JAVA划时代的一个版本，几乎是让JAVA焕发了第三春（第二春在JDK5），当然里面的新特性也是十分重要的，虽然Java现在都已经到了10几的版本，但是国内多数使用的版本还是JAVA8，所以这个系列将会围绕Java8的新特...

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JAVA8实战 - Optional工具类（下）

Optional的使用场景从个人角度来说其实使用不是很方便，下面说下Optional的工具使用场景：1. 封装可能为Null的值还是和所说的Map类似，当我们使用下面的操作获取值的时候，就很容易引发null：User user = (User)map.get("user"); 复制代码于是....

java8特性 Optional 工具类

1. 关于Java8工具类Optional的一点使用心得对于Java开发中遇到的npe（空指针问题），其实使用工具类Optional处理效果一般，个人感觉最大的用处就是可以减少一定的if语句，减少一定的非空判断，千万不能将Optional放在if内，会非常多此一举。个人觉得最实用的例子ÿ...

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