The CodingBat website contains dozens of lessons in both Java and Python, allowing the user to learn at their own pace. Most of the website consists of coding exercises automatically checked by the server, giving the student immediate feedback and stats on their coding. There are also videos, links to relevant internal and external sites, and the ability to save progress with optional account creation. The website mostly focuses on logical rearrangement of data abstractly.
Learn Java by typing code solutions to posed problems. Practice-It is the University of Washington’s partially-open access (with an account that must be created before first use) practice system for Java. It contains introductory and advanced lessons that come from the textbook used for the courses offered there. The user attempts to solve coding problems by typing their solutions which are then checked to see if they produce the correct result.