got java,jdk,bytecode?

In computer science, an instruction set architecture (ISA), also called computer architecture, is an abstract model of a computer. A device that executes instructions described by that ISA, such as a central processing unit (CPU), is called an implementation.

An intermediate representation (IR) is the data structure or code used internally by a compiler or virtual machine to represent source code. An IR is designed to be conducive for further processing, such as optimization and translation.[1] A "good" IR must be accurate – capable of representing the source code without loss of information[2] – and independent of any particular source or target language.[1] An IR may take one of several forms: an in-memory data structure, or a special tuple- or stack-based code readable by the program.[3] In the latter case it is also called an intermediate language.

1. https://en.wikipedia.org/wiki/Intermediate_representation
2. https://github.com/heidsoft/jdk
3. http://openjdk.java.net/
4. https://www.csie.ntu.edu.tw/~comp2/2001/byteCode/byteCode.html#A%20Little%20Big
5. https://stackoverflow.com/questions/14434320/javap-in-a-programmable-way
6. https://wiki.openjdk.java.net/display/loom/Main
7. https://tech.meituan.com/2019/09/05/java-bytecode-enhancement.html