1、开发工具概述
IDEA是一个专门针对Java的集成开发工具(IDE)，由Java语言编写。所以，需要有JRE运行环境并配置好环境变量。它可以极大地提升我们的开发效率。可以自动编译，检查错误。在公司中，使用的就是IDEA进行开发。
2、IDEA 软件安装
2.1、进入官方网下载
地址：https://www.jetbrains.com/idea/
2.2、安装
欢迎界面
选择安装路径
配置安装选项
开始菜单
安装完毕
3、配置
选择不导入任何设置，点击 OK。
选择主题
填写对应版本的激活码（版本2019 2.3）
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4、创建项目
选择 Create New Project
点击 new 按钮，配置安装 JDK 版本
选择 JDK 目录，点击确定
点击Next
不使用模板
为工程起名字 demo1 ，并存储到 E:\IdeaProjects\demo1 目录下，如果E盘没有这个目录，会自动创建。
到这里我们的项目已经创建好了，如果再新建项目，点击 File ->new->Project
5、创建包和类
展开创建的工程，在源代码目录 src 上，鼠标右键，选择 new ->package ，键入包名 com.itheima.demo （表示创建了多级的文件夹），点击确定。
新建java文件
写一段代码，右键运行
完成！