Writing a “Hello World” program is often a rite of passage for a software engineer when learning a new language.

If you’re a Java developer,  you might even remember the first time you typed public static void main(String[] args) in your editor of choice. But did you ever wonder what’s inside that “.class” file that the compiler spits out? Let’s look at how we can write a JVM “Hello World” by creating a class file programmatically.

We’ll work through creating a class file for the following simple Java Hello World application.