arthas打印的 main class 失效，在新版本jdk里获取失败 #2990
Description
wiki https://arthas.aliyun.com/doc
tutorials https://arthas.aliyun.com/doc/arthas-tutorials.html
version 4.0.4
main_class
pid 5188
之前是从 env 里获取，需要改为 System.getProperty("sun.java.command", "");。