On the fly java compiler in javascript

Question

I'm trying to build an online java editor. I need the functionality that enables me to report the compilation errors to the user on clicking submit if there are any. I'm curious to know if there are any javascript libraries out there that I could use off the shelf to do this.

Answer 1

Take the text and call javac on it on the server side, send back the results in some structured way and display on the client side