You’re invited to check out out all the different learning resources in the guide: problems and projects, former Google interview questions, online courses, education sites, videos, and more.
Object Oriented Java Programming: Data Structures and Beyond Specialization, University of California San Diego
Take your Java skills to the next level with this intermediate course series that features real-world project contributions by Google. You'll learn to efficiently organize large datasets and assess the quality of your own code. (paywall)Open link