"Happy birthday, Tobias! Hope it’s a great one."
Codetown
Codetown ::: a software developer's community
Codetown is a software developer's community. It's a technical networking and educational group focused on software development.
Videos
Photos
JavaSpecialists
Issue 331 - Virtual Thread States
No major feature has been adopted as quickly into production systems as virtual threads. Not generics. Not streams. But there are some catches. Original Java threads have six states. Virtual threads have 20 states, which Java maps onto the original six states. However, sometimes it can be useful to know what the virtual threads state is. In this newsletter we use deep reflection to learn how that works.Issue 330 - Looking Back on 25 Years
Today marks our 25th newsletter anniversary, when I sent out an email to 80 colleagues and friends. To celebrate, we are looking at some of the most popular newsletters over the years. Thanks for being part of this adventure.Issue 329 - Filtering Exceptions via try
One of the ways of figuring out the type of an exception is with instanceof. Another is to re-throw it, and to use the catch mechanism to sort things out. In this newsletter we look at different options, including switch with pattern matching.Issue 328 - Negative size() in LinkedBlockingDeque
The LinkedBlockingDeque has an interesting feature in addAll(), where they first build up the linked nodes and then add them all to the tail. However, a bug allowed us to overflow the size, resulting in a negative count. In this newsletter we look at this bug, and also how it was fixed in Java 26.Issue 327 - ShuffleGatherer
Instead of shuffling our stream at the end in the collect() method, we can also shuffle it in stages using the new stream gatherers. This allows us to shuffle sections at a time and even support infinite streams.Birthdays
Birthdays Today
Birthdays Tomorrow
Badge
Who Reads Codetown?
Events
Blog Posts
New Java features
Posted by Michael Levin on August 29, 2025 at 5:32pm 0 Comments 0 Likes
August 28 2025, Newsletter no. 297 (this newsletter is available in html format at http://www.javaperformancetuning.com/news/news297.shtml )
As usual before a Java release, I'm listing all the new…
Free Eclipse book, recently published
Posted by Michael Levin on August 24, 2025 at 11:59am 0 Comments 0 Likes
ContinueHi Everyone,My publisher is running a free Amazon Kindle book promotion through Monday, August 25th, 2025. The book, “Eclipse Collections Categorically: Level up your programming game” can be obtained for $0 on Kindle on Amazon through the August 25th.…
What is vibe coding?
Posted by Michael Levin on June 9, 2025 at 9:37am 0 Comments 0 Likes
Vibe coding isn’t a formal technical term, but it’s become a slang or colloquial expression among programmers and tech communities—especially on social media and in creative coding circles.
What “vibe coding” usually means:
- Coding based on intuition or feel
Instead of rigidly planning everything out, you’re:- Freestyling as you…
You can now download the source code that sparked the AI boom
Posted by Michael Levin on March 25, 2025 at 4:30am 0 Comments 0 Likes
Learning about artificial intelligence? You may find this interesting.
https://arstechnica.com/ai/2025/03/you-can-now-download-the-source-code-that-sparked-the-ai-boom/
Groups
-
Kotlin Town
6 members
-
Computational Linguistic…
15 members
-
Jobs
75 members
-
Contest Town
9 members
-
Community Corral
23 members
-
Scala
5 members
-
Freelance Village
11 members
-
iPhone Development
40 members
-
Ruby Town
14 members
-
Clojure
8 members
-
Groovy and Grails
25 members
-
Other Languages on the J…
9 members
-
Java SE Town
14 members
Forum
Java books for any library 5 Replies
What books should be on the bookshelf of EVERY Java programmer, no matter what specific technologies they are working on?The two that come to my mind areThinking in JavaJava Concurrency in PracticeWhat else am I missing?Continue
Started by David Moskowitz in Java. Last reply by sneha gulati Feb 8, 2019.
Error trying to use Fragment
I am new to Android. I have been working thru some examples in a book called Head First Android Development. I entered a small program using fragments and get a Casting Error.cannot cast andoid.app.fragment to…Continue
Tags: Fragment
Started by Robert Sobol in Java Oct 10, 2017.
Fragment Syntax Problem
My name is Rob Sobol.I have been working through a book called Head First Android Development.I hit a syntax error in a simple exercise that uses one fragment. I have been trying to figure out the error for days. I am hoping some in the forum can…Continue
Tags: Fragments
Started by Robert Sobol in Java Oct 10, 2017.
Hadoop getting old?
An article just came out in InfoWorld about trends, which is always an interesting subject. Funny, they said Hadoop wasn't hot. Spark is. It's a good read. …Continue
Tags: codetown, infoworld, programming, hadoop, trends
Started by Michael Levin in Trends Apr 10, 2017.
What's functional programming, anyway?
Can you believe people are still trying to come up with a good definition or explanation of what functional programming is? Paul Krill is a journalist with InfoWorld. Here's an article he just wrote: …Continue
Tags: functions., codetown, lambdas, clojure, programming
Started by Michael Levin in Functional Programming Feb 21, 2016.
Santafe College 2 Replies
Santafe just added a new BAS bachelor's program of study. 5651 ProgrammingContinue
Started by Dan Lackey in Dynamic Languages. Last reply by Michael Levin Feb 15, 2016.
Using SQL with Node,.js 1 Reply
All the tutorials and books for node.js seem to use Mongo as the database. I am not sold on 'document' databases and would like to know how difficult it is to use any version for plain old tried-and-true SQL with Node.js.Does anybody have any…Continue
Tags: 'document, databases', SQL, node, node.js
Started by Kevin Neelands in Dynamic Languages. Last reply by Lou Caudell Nov 10, 2015.
The advantages of a RESTfull web-based API 5 Replies
I need to get a better handle on the advantages of a RESTful web-based API. People tell me they scale better than other methods, but I don't see how they reduce database access or have any other feature that helps handle large amounts of traffic.…Continue
Tags: API', 'web-based, RESTful
Started by Kevin Neelands in Dynamic Languages. Last reply by Kevin Neelands Oct 25, 2015.
Want a Job? 1 Reply
Hi, Not sure if this is the appropriate place to post this sort of things (forgive me if its not). My company (really nice company btw) is looking to hire two junior and two senior Java Developers. Please forward me your resume to slaassel@gmail.com…Continue
Started by Saad Laassel in Java. Last reply by Theresa Wizorek-MacIntyre Oct 15, 2014.
Storing Sensitive Data ( like SSNs ) 1 Reply
We might have to store Social Security Numbers. We REALLY don't want to do this in our own database, we'd like some external 'vault' service that stores them encrypted and getting to them is difficult. Does anyone have any ideas along these lines?Continue
Started by Kevin Neelands in Java. Last reply by Michael Levin May 7, 2014.
Latest Activity
Ever wondered how companies gauge customer interest? Discover the surprising tactics from Expedia...
In an intriguing throwback, key insights from the life of Dara Khosrowshahi unveil how seemingly ineffective strategies, like implementing a non-functioning ...
Happy 10th year, JCertif!
Notes
Welcome to Codetown!
Codetown is a social network. It's got blogs, forums, groups, personal pages and more! You might think of Codetown as a funky camper van with lots of compartments for your stuff and a great multimedia system, too! Best of all, Codetown has room for all of your friends.
When you create a profile for yourself you get a personal page automatically. That's where you can be creative and do your own thing. People who want to get to know you will click on your name or picture and…
ContinueCreated by Michael Levin Dec 18, 2008 at 6:56pm. Last updated by Michael Levin May 4, 2018.
Looking for Jobs or Staff?
Check out the Codetown Jobs group.
InfoQ Reading List
Java News Roundup: Oracle Critical Patch Update, Grizzly 5, Payara Platform, GraalVM, Liberica JDK
This week's Java roundup for January 19th, 2026, features news highlighting: JEP 527, Post-Quantum Hybrid Key Exchange for TLS 1.3, targeted for JDK 27; GlassFish Grizzly 5.0; the quarterly release of the Oracle Critical Patch Update (CPU) Advisory; the January 2026 edition of the Payara Platform; and maintenance releases of Liberica JDK, GraalVM, OpenXava and Ktor.
By Michael RedlichOpenAI and Anthropic Introduce Healthcare-Focused AI Platforms
OpenAI and Anthropic have announced new healthcare-oriented AI offerings that extend their models beyond general conversational use and into regulated clinical and life sciences environments. Both releases emphasize technical integration, interoperability, and governance, reflecting a shift toward AI systems designed to operate directly within existing healthcare infrastructure.
By Robert KrzaczyńskiArticle: The Friction Fix: Change What Matters
Friction is the invisible current that sinks every transformation. Friction isn’t one thing, – it’s systemic. Relationships produce friction: between the people, teams and technology. The fix isn’t Kubernetes, the Cloud or AI. The fix is changing our patterns of thinking, communicating, and organizing.
By Cat Morris, Diana MontalionCedar Joins CNCF as a Sandbox Project
Cedar, an open-source policy language architected by AWS, has joined the CNCF as a Sandbox project. Designed for fine-grained application permissions, it decouples access control from code using a verifiable, high-performance policy engine. Cedar supports RBAC, ABAC, and ReBAC, offering a secure, analyzable alternative to general-purpose tools like OPA.
By Mark SilvesterPresentation: Theme Systems at Scale: How To Build Highly Customizable Software
Guilherme Carreiro discusses the architecture behind Shopify’s theme system, focusing on balancing extreme customizability with platform stability. He explains how they leverage Liquid as a safe DSL, optimize performance via native extensions (Rust/C), and use JSON schemas to bridge the gap between developers and merchants.
By Guilherme Carreiro
© 2026 Created by Michael Levin.
Powered by
