JAVA代码审计若干问题（一）

作业：
1、配置多版本jdk环境并实现通过cmd进行临时切换
将java1.8与java11置于同一文件夹，创建run文件夹，创建java11.bat脚本打开系统环境变量，path中添加run文件夹打开cmd命令行模式键入java -version再键入java11,java -version，发现切换成功！
2、安装和启动tomcat，并部署简单的web项目，访问后输出helloworld
https://tomcat.apache.org下载tomcat8.5下载完成后解压，打开bin文件夹点击启动startup.bat返回上级目录，打开webapp文件夹，创建test目录，打开它，创建index.html用vscode别写如下代码在浏览器中打开
3、安装并破解idea，使用idea创建一个helloworld工程，运行之后输出三次helloworld，并打包该项目
下载安装包后，点击下一步选择要安装的路径勾选以下选项
下一步，点击安装勾选复选框，点击完成退出程序，下面开始破解
下载jetbra.rar，解压缩后进⼊到⽂件夹 /jetbra ，⽬录如下：进入点击破解补丁点击确定出现Done，表示激活成功重新打开IDE，在IDE激活码中复制以下激活码

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激活成功！点击创建新项目新建java类打印三遍helloworld,点击构建工件旁边生成out文件夹，下面进行打包成jar文件，点击设置里的项目结构点击添加工件件点击应用点确定点击构建工件发现已打包成jar文件
4、使用idea进行远程调试，调试的对象是第三步生成的jar包
点击编辑配置
添加JVM远程调试重命名，点击应用确定
打开项目结构选择sdk为1.8版本
选择helloworld重新进行编译输入以下命令可以看到远程执行成功下面，把n改为y,idea里点击调试，可以看到，执行到断点位置
5、系统复习javase基础知识

预习：java web

预习资料：
https://www.liaoxuefeng.com/wiki/1252599548343744/1255945497738400