What version of java does codecademy teach?
ECMAScript 2015 ECMAScript 6 (ES6) ES6+ ES7 and beyond
As for Java, that is a question that someone else will have to answer. The two languages are not connected but for the earlier years when Netscape and Sun Microsystems got together. Those days are long since past and ECMA is now the guardian or standard bearer for the ES language. Sun is now Oracle, and if Java is your interest, be sure to make yourself familiar with their online learning resources while you study the language. It is to Java what W3C, ECMA and MDN are to browser APIs.