Java

I just applied for Amazon Technical Academy. It requires learning Java. I know Java, but not very deeply. Here are resources an Amazon cohort shared with me. Books and Blog Posts Head First Java (free version) Practice and Challenges CodingBat Java — Various practice exercises Advent of Code — A series of puzzles for problem solving and coding Online practice tests for Java Certification: http://www.gocertify.com/quizzes/oracle/ocajp-java-quiz-1.html https://www.javatpoint.com/core-java-quiz https://www.examsnet.com/exams/ocjp-certification-practice-online Talks A humorous talk on silly programming language behavior A good talk on data structures, with examples in Java, C#, and Python (3 hours) Dev Resources REPL.It — Online Java Editor/Playground IntelliJ Java IDE (use the community version) JaCoCo Code Coverage