Java特性类的相关内容

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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Java8特性第三讲：如何使用Optional类优雅解决业务npe问题

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...

[帮助文档] 如何快速为当前Java类补充所需要的注解

本文介绍如何快速为当前Java类或当前目录下所有Java类补充所需要的注解，例如：@Field、@Method、@Param等注解。对于注解的name与desc，如果在存在JavaDoc的情况下，IDEA会从JavaDoc进行读取，如果不存在，将会以FieldName/MethodName作为注解的...

java8新特性：Optional类

总结于尚硅谷学习视频视频链接https://www.bilibili.com/video/BV1Kb411W75N?p=685代码OptionalTest类package com.day0330_1; import org.junit.jupiter.api.Test; import java.ut...

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，...

Java8特性-Optional类深度解析下

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、Ceylon...

Java 8 新特性 Optional 类学习，理解并应用。NullPointerException空值检测

Optional 类JDK1.8开始引入的特性，Optional 类主要解决空指针异常（NullPointerException）问题。Optional类是一个可能包含或不包含非空值（可以为null）的容器对象。如果一个值存在，调用 isPresent()方法将返回true、get()方法将返回该...

Java8新特性——Optional容器类的简单应用

1.Optional容器类Optional<T>类(java.util.Optional) 是一个容器类，代表一个值存在或不存在，原来用 null 表示一个值不存在，现在 Optional 可以更好的表达这个概念。并且可以避免空指针异常。常用方法：· ...

Java8新特性之Optional类

前言文本已收录至我的GitHub仓库，欢迎Star：github.com/bin39232820…种一棵树最好的时间是十年前，其次是现在絮叨今天开始写Java8新特性系列，怎么说呢，主要有几个新东西Lambda表达式函数式接口方法引用Stream流Optional类default关键字这个四个的主...

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