It does its job and it does it well. It's fast, battle-hardened, and has a huge ecosystem.

But there are a few really clunky things about it. My biggest problem is that everything I write feels like a second-class citizen. There is no operator overloading. There is no way to replicate the behavior of primitives. The primitives and operators set in stone.

This wouldn't be such a huge problem except that Java's selection of primitives and operators is awfully limiting. There are no unsigned integers at all. There's no long double or long long int.

This means that some simple tasks are cumbersome and filled with boilerplate. If you want to compute (a + b) < c using unsigned 128-bit integers, you'll have to write something like (a.add(b).compareTo(c) < 0). It works fine. It isn't a real problem for big enterprise projects. It's just ugly as sin.

Try out Java's BigInteger class. Then try a language like Python or Haskell or Scala for comparison and you'll see the difference.

If you're taking AP CS, it's especially bad for you. You should be using something simple and clean like Python, not a clunky workhorse like Java.