jvm虚拟机

1.JVM基础入门
javac命令会把X.java文件转换成X.class文件
ClassLoader（字节解释器） java类库
jvm是一种规范
https://docs.oracle.com/en/java/javase/13/index.html
https://docs.oracle.com/javase/specs/jvms/se15/jvms15.pdf
2.常见的JVM实现
Hotspot oracle
Jrockit BEA
J9 IBM
Microsoft VM
TaobaoVM
LiquidVM
azul zing www.azul.com