The production of a simple virtual machine is easy stuff. It is just a giant switch statement which calls easy to write functions to execute the decoded instruction. If you have the Backus-Naur for the language a top-down, recursive descent compiler is also trivial to write. You can type in the code for it almost as fast as you can read the grammar. The production of the initial libraries was also pretty straight-forward. There was a ton of C code around that could be referred to and translated into Java. The whole job took about two weeks to deliver. Hey presto: Java was born and made freely available for download on Sun's website. Java 1.0 was tiny.

Now, here is the spooky bit. I typed in a grammar that more or less exactly matched the Java programming language into a terminal in the computer science lab at university thirty years ago. The terminal was a Sun box and connected to the Internet. Two weeks later after I had done this Java appeared on Sun's web site. Od that, strange that, huh?