On-the-fly java compiler in javascript

Question

I am trying to create an online java editor. I need functionality that allows me to report compilation errors to the user when I click the submit button, if any. I am curious to find out if there are javascript libraries there that I could use from a shelf to do this.

Answer 1

Take the text and call javac on it on the server side, send the results in some structured form and show on the client side