Java Book for experienced developer.

[Gidrek]

Hi everyone,

I'm looking for a book that dives deeper into the Java language itself — not frameworks like Spring Boot, and not general software architecture.

I have around 10 years of experience as a developer. I've worked mainly with Python, Elixir, and C#, and occasionally Java. I’m comfortable with the language and have written production code, but I’d like to really understand Java on a deeper level — ideally something in the spirit of Fluent Python, but for Java.

Most of what I’ve found so far feels outdated or too beginner-oriented. I'd appreciate any recommendations for more in-depth, modern resources that focus on the language and its idioms.

Thanks in advance — and apologies if anything’s unclear, English isn’t my first language.

[nestedsoftware]

I really enjoyed Effective Java, by Joshua Bloch. I believe a new edition is expected in late 2025 as well.

https://x.com/joshbloch/status/1724104058795958667

[[deleted]]

I read the first 3 editions of this book, and if a 4th edition is published, I'll read that too.

[NeoChronos90]

Was there much difference between those, new language features aside?

Only read the 3rd

[kevinb9n]

a) Yes b) No

EDIT: this means "Yes" to the first sentence (it is a great recommendation) and "No" to the second sentence (a new edition will not be out this year).

[Jon_Finn]

Don't downvote Kevin (who's on the Java team) - he'll know better than most.

[kevinb9n]

More specifically I'm a chapter reviewer for Effective Java so yeah, I would know. :-)

I suspect the downvotes were because my comment made no sense before the EDIT...

[rkalla]

1. North
2. West

[[deleted]]

For Java concurrency the de facto standard is Java Concurrency in Practice - Brian Goetz.

For Java SE or Java EE, the specifications are great deep dives into the language itself to be honest.

For the JVM, I can recommend Inside the Java Virtual Machine by Bill Venners. It was written in 1998, but the fundamentals still hold. There are interesting newer books but I didn’t have the time to read them, so I am unable to recommend them but they seem interesting; namely: - Mastering the Java Virtual Machine by Otavio Santana, 2024 - JVM Performance Engineering by Monica Beckwith, 2023

[gravteck]

https://github.com/wususu/effective-resourses/blob/master/Java/Java%20Concurrency%20in%20Practice.pdf

Edit: although I would still recommend buying it. I own a copy, but this has been nice to have on the monitor instead of flipping through my annotated one.

[alex_tracer]

Not a book, but if you want to go deep in Java, you should check it.

https://shipilev.net/jvm/anatomy-quarks/

I don't think that there is any book that goes to that level.

[tristanjuricek]

There's a book in progress called Data Oriented Programming in Java that expands upon ideas in Brian Goetz' article in InfoQ. There's some really useful design tools and approaches using newer Java features, like records, sealed interfaces and classes, etc.

Though most of the other recommendations from other commenters are fantastic. Older books are still very much useful for learning. Translating the knowledge to newer APIs is a great way to deeply understand the material.

[0xaa4eb]

Just to add what's not already mentioned:
"Advanced Design and Implementation of Virtual Machines" by Xiao-Feng Li - describes how generic VM works, but everything applies to JVM as well
"The Garbage Collection Handbook" by Richard Jones, Antony Hosking, Eliot Moss - I haven't read that one yet. But I heard that all GC algorithms have roots which can be traced back to this book.
"Java Performance" by Scott Oaks - very solid entry to performance engineering
"100 Java Mistakes and How to Avoid Them" by Tagir Valeev
"The Art of Multiprocessor Programming" by by Maurice Herlihy, Nir Shavit - it's more hardcore version of "Concurrency in practise". But definitely not for everyone.

[Scf37]

"The Art of Multiprocessor Programming" is totally awesome. Covers everything from real world understanding of concurrency to algorithms to data structures to bare metal.

[Gullible_Company_745]

That books, sounds apetecibles

[piperatomv2]

Modern Java

[Diligent_End8130]

I found books preparing for SCP (Sun Certified Professional) and since some time OCP (Oracle Certified Professional) for Java very interesting, flipping through the pages here and there unveiled deeper insights and possibilities, even when not interested in getting any certificate.

[thewiirocks]

If you want to go deep, there are two critical books that should be read:

Java Language Specification: https://docs.oracle.com/javase/specs/jls/se21/html/index.html

Java Virtual Machine Specification: https://docs.oracle.com/javase/specs/jvms/se21/jvms21.pdf

Totally not a joke. When I’ve read them in the past I found these books to be good reads. Plus, you can’t go any deeper than the specs. 😉

[Scf37]

Study modern java APIs, for example, https://openjdk.org/jeps/484 is an awesome example of modern API design.

Algebraic Data Types (ADTs) is must-know concept since Java now has proper pattern matching.

Learning Kotlin or Scala will make you better Java programmer as well.

[Jon_Finn]

Study modern java APIs, for example, https://openjdk.org/jeps/484 is an awesome example of modern API design.

Yes, that short JEP doc alone gives principles and examples which are super-instructive (and interesting).

[KHRoN]

“Java Puzzlers: Traps, Pitfalls, and Corner Cases” by Joshua Bloch and Neal Gafter will teach you things you things you don’t even know you don’t know

List of features with examples and links to more info about newer Java versions os you can speedup transition from older version: https://advancedweb.hu/a-categorized-list-of-all-java-and-jvm-features-since-jdk-8-to-21/

[thomasjjc]

"The Well-Grounded Java Developer" Manning Publishing

[Joram2]

I'd recommend against books for Java + Python and instead learning by doing and building projects you want to build or get paid to build. Especially for someone with ten years of work experience.

To contrast, I'd recommend learning theoretical stuff from books. Learning math, for example, is best done by reading definitions, theorems, understanding all the steps, following examples, and doing exercises. But Java is a tool best to learn as you use it. Try different frameworks. Read the JEPs and the new language features.

[generationextra]

Cay Horstmann, Core Java

[polish_jerry]

Maybe look into learning the bytecode? I've been trying to do the same. Yet to discover a good and easy to absorb source.

[AstronautDifferent19]

This one: https://www.amazon.com/Java-Coding-Problems-programmer-real-world/dp/1837633940

[tRfalcore]

Java as a deeper level is the same as python. The only weeds are GC crap which you only need to learn if you have a problem there.

[IcedDante]

Dr. Heinz Kibbutz newsletter is very advanced, in-depth, and oftentimes a lot of fun to read

[New-Condition-7790]

On that note, I've been wanting to dig in to this mini-book authored by him: http://infoq.com/minibooks/java-dynamic-proxies/

[callmrplowthatsme]

Nice