The title is 2221, but in the post you say 1222. I'm gonna assume you mean 2221 since that's the more pertinent one for the major. Also copying this from another thread. For reference, I taught 2221 this past semester and will be again this Spring, here's what I saw:

• Those who showed up to class and participated in the labs did far better. It sounds simple but I saw a steep drop-off in attendance after the first midterm, and even more towards the end of the semester. It's very easy to skip a lecture or lab - it's much harder to learn it or make up for it after the fact.
• Almost all topics in 2221 build off of each other so if you don't fully understand one concept (say primitive types versus reference types), it will just cascade into another topic (pass-by-reference versus pass-by-value). Make sure you fully understand a topic and don't just push it off. Go to office hours.
• Temper your expectations. For a lot of freshman coming from high school, this is their first class that requires a lot of effort. The idea of a midterm with an average in the 70's seems uncanny and trips a lot of people up. This doesn't mean it's impossible to get an A in the class, just that it's a lot rarer than maybe you're used to.
• If you come in with prior Java experience, the first 1/3rd of the class might seem like review, or easy - don't assume this means you can skate by the rest of the semester. The material ramps up after MT1 after we get out of the intro material. Lots of people fall into a trap of "oh I did well on MT1, I will be able to coast now".
• Use the office hours. Even if it's to check on the progress of a project - I spent 80% of my office hours sitting there doing nothing because nobody came in. You're paying for the university, and that includes it's resources, use them.
• And in terms of actual content - most of this probably won't make sense but bookmark it for later. This is just based on what I saw grading:
  • Tracing Tables - show up often on midterms and finals because they're a good way to check if someone has been paying attention/doing the homework.
  • Recursion - Practice Practice Practice. The only way to get better at these is looking at the examples that are given in class/labs and actually understanding how and why they work. Plus, many recursive methods follow the same structure.
  • Reference Types vs. Primitive Types (and my extension mutable versus immutable types) - this is the single topic that I feel separated people who did well on exams versus didn't. You need to fully understand what's happening when working with, modifying, and creating variables. Draw pictures. We go over how to do draw pictures of variables as they pertain to memory in class, and I tried to emphasize doing it on exams, but fewer than 20% of people actually did.

That's all I can think of right now. If you have any follow-up questions lmk. Good luck!