The source of learning is learning from others.

Magazines.

Recommended magazines:

• Java Magazin (german)
• Objekt Spektrum (german)
• Informatik-Spektrum (german)
• c’t (german)

Books

Highlights of books:

• Code Complete: A Practical Handbook of Software Construction
• Effective Java: A Programming Language Guide
• Java Concurrency in Practice
• The Pragmatic Programmer. From Journeyman to Master
• Refactoring: Improving the Design of Existing Code
• Refactoring to Patterns
• Refactorings in grossen Softwareprojekten
• xUnit Test Patterns: Refactoring Test Code
• Continuous Integration: Improving Software Quality and Reducing Risk
• GoF Design Patterns
• Head First Design Patterns
• Patterns of Enterprise Application Architecture
• Enterprise Integration Patterns
• REST und HTTP
• Domain-Driven Design
• Why Programs Fail: A Guide to Systematic Debugging
• Software-Wartung: Grundlagen, Management und Wartungstechniken
• The Mythical Man Month: Essays on Software Engineering
• Adrenaline Junkies and Template Zombies: Understanding Patterns of Project Behavior
• Software Teamwork: Taking Ownership for Success
• Pragmatic Thinking and Learning: Refactor Your Wetware (Pragmatic Programmers)
• Coders at Work
• Soft Skills für Software-Entwickler
• Release It!: Design and Deploy Production-Ready Software
• The Power of Less: The Fine Art of Limiting Yourself to the Essential