- Effective Java - Third Edition
- Effective Java - Second Edition
- Java Concurrency In Practice
- Java SE 8 For the Really Impatient
- https://github.com/EbookFoundation/free-programming-books/blob/master/free-programming-books.md#java
- Java Video Tutorial
- Learn Java Programming with examples
- Java Tutorial for Complete Beginners
- Java for Complete Beginners (registration required but free)
- Complete Java Masterclass (highly recommended)
- Java Essential Programming