Java's a pretty good beginning programming language. Outside of the mystical incantation of `public static void main(String[] args) {` and what the difference between `new ArrayList` and `ArrayList.new()` is (I still don't know but I haven't really touched it since college), it's a good statically typed imperative language that you can throw objects and functional stuff into when it's time, isn't going to give you weird errors about indentation, has just enough pointers for you to learn how to avoid a `NullPointerException`, does things pretty "conventionally" (ie, there's not a lot in Java that doesn't also show up in other languages), and is easy to compile and run (when you're not using 3rd party libraries, which students in something like a Data Structures and Algorithms class aren't going to be using). Ideally you have another class teaching you another language too so you get the double bonus of learning what a language is and what a language isn't, and Python's good for that, but by itself Java's fine