Reading about features only goes so far. You learn the most by building something start to finish. Here are project ideas that combine what you already know with topics from this section.
To-do list app. Store tasks in a file using File I/O. Use an ArrayList to manage items in memory.
Student grade tracker. Read scores from a CSV. Use streams to calculate averages and filter students below a threshold.
Quiz game. Define categories with enums. Track scores per category in a HashMap.
Simple REST API. Use Spring Boot to serve a list of items with create, read, update, and delete endpoints.
Pick one and start coding. Solving problems along the way teaches more than any tutorial.