怎样将java的class文件生成jar包

1.如Java文件

2.进入.class的目录最外层org的界面

3.打开命令窗口输入如下指令：jar -cvf hello_agent.jar org

4.运行 java -javaagent:hello_agent.jar=xunche org/xunche/app/HelloWorld

5.解决 Failed to find Premain-Class manifest attribute in hello_agent.jar 问题

Manifest-Version: 1.0
Created-By: 1.8.0_191 (Oracle Corporation)
Main-Class: norepeat.NoRepeatApp
Premain-Class: org.xunche.agent.HelloAgent
Can-Redefine-Classes: true
Can-Retransform-Classes: true
Agent-Class: org.xunche.agent.HelloAgent

6.再次运行