Top books on r/java

Effective Java (2nd Edition)

Clean Code

Head First Java, 2nd Edition

Java Concurrency in Practice

Java: A Beginner's Guide, Sixth Edition

Head First Design Patterns: A Brain-Friendly Guide

Growing Object-Oriented Software, Guided by Tests

Effective Java (3rd Edition)

Working Effectively with Legacy Code

Java Puzzlers: Traps, Pitfalls, and Corner Cases

Patterns of Enterprise Application Architecture

Java Performance

Code Complete

OCA: Oracle Certified Associate Java SE 8 Programmer I Study...

Java Performance

Design Patterns

Java: The Complete Reference, Ninth Edition

OCA/OCP Java SE 7 Programmer I & II Study Guide

Thinking in Java (4th Edition)

Core Java Volume I--Fundamentals

The Pragmatic Programmer

Domain-Driven Design

1: Core Java Volume I--Fundamentals

Java: How to Program, 9th Edition (Deitel)

Agile Principles, Patterns, and Practices in C#

Java Generics and Collections

Data Structures and Algorithms in Java