97 Things Every Java Programmer Should Know , edited by Kevlin Henney and Trisha Gee, is a collection of brief, expert essays that cover technical and professional wisdom specific to the Java ecosystem. Amazon.com Key Themes and Insights
You can find the PDF on GitHub by searching for community-maintained repositories that host technical book collections. However, note that the book is copyrighted by O'Reilly Media (edited by Kevlin Henney and Trisha Gee). 97 things every java programmer should know pdf github