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1.简介 Java 8引入了一个重要的新特性，即Optional类。Optional类是为了解决空指针异常而设计的。在Java中，当我们尝试访问一个空对象的属性或调用其方法时，很容易抛出NullPointerException。这种异常可能会导致程序崩溃或产生意外结果。 Optional类的目的是...

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Java8新特性 Optional类

Optional类到目前为止，臭名昭著的空指针异常是导致Java应用程序失败的最常见原因。以前，为了解决空指针异常，Google公司著名的Guava项目引入了Optional类，Guava通过使用检查空值的方式来防止代码污染，它鼓励程序员写更干净的代码。受到Google Guava的启发，Opt...

java 8 新特性讲解Optional类--Fork/Join 框架--新时间日期API--以及接口的新特性和注解

Optional类到目前为止，臭名昭著的空指针异常是导致Java应用程序失败的最常见原因。以前，为了解决空指针异常，Google公司著名的Guava项目引入了Optional类，Guava通过使用检查空值的方式来防止代码污染，它鼓励程序员写更干净的代码。受到Google Guava的启发，Optio...

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1、背景身为一名Java程序员，大家可能都有这样的经历: 调用一个方法得到了返回值却不能直接将返回值作为参数去调用别的方法。我们首先要判断这个返回值是否为null，只有在非空的前提下才能将其作为其他方法的参数。这正是一些类似Guava的外部API试图解决的问题。一些JVM编程语言比如Scala、Ce...

java8新特性：Optional类

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Java 8 特性之Optional用法详解

前言 NPE（NullPointerException）一直是Java程序员最深恶痛绝的异常，冗长的非空校验使代码的可读性和优雅性都大大降低。那么本篇文章，笔者将详细介绍一下Java 8 引入的特性--Optional类，看看它是如何避免空指针异常的。什么是Optional？ Optional是一...

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本篇Blog继续学习和实践Java8中的新特性，主要分为两大部分：语言新特性和库函数新特性，重点落在工作中经常会用到的几个重大特性：语言新特性：Lambda表达式，方法引用，接口的默认方法和静态方法，重复注解库函数新特性：Optional，Streams&#...

Java8新特性之Optional类

引言在文章的开头，先说下NPE问题，NPE问题就是，我们在开发中经常碰到的NullPointerException，NPE是十亿美元的错误，任何编程语言70%以上的异常都是NPE，假设我们有两个类，他们的UML类图如下图所示：目的：为了避免一系列的if判空，...

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