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JavaSpecialists

Issue 332 - ForkJoinPool.asyncCommonPool()

The common ForkJoinPool refuses to tell us its exact parallelism, in order to spare us embarrassing division by zero errors. The effect is that the rest of the concurrency framework has had to create dangerous workarounds to counteract a possibly zero sized pool. Since Java 25, the ForkJoinPool will silently create a couple of threads to make CompletableFuture (and others) safer to use. In addition, ForkJoinPool has become a ScheduledExecutorService, thus we can use the common ForkJoinPool as a global timer.

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.


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New Java features

Posted by Michael Levin on August 29, 2025 at 5:32pm 0 Comments

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…

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Free Eclipse book, recently published

Posted by Michael Levin on August 24, 2025 at 11:59am 0 Comments

Hi 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.…
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What is vibe coding?

Posted by Michael Levin on June 9, 2025 at 9:37am 0 Comments

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:

  1. Coding based on intuition or feel

    Instead of rigidly planning everything out, you’re:

    • Freestyling as you…
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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.

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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…
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InfoQ Reading List

Presentation: Beyond the Warehouse: Why BigQuery Alone Won’t Solve Your Data Problems

Sarah Usher discusses the architectural "breaking point" where warehouses like BigQuery struggle with latency and cost. She explains the necessity of a conceptual data lifecycle (Raw, Curated, Use Case) to regain control over lineage and innovation. She shares practical strategies to design a single source of truth that empowers both ML teams and analytics without bottlenecking scale.

By Sarah Usher

Java Explores Carrier Classes to Extend Data-Oriented Programming Beyond Records

The OpenJDK Amber project has published a new design note proposing “carrier classes” and “carrier interfaces” to extend record-style data modeling to more Java types. The proposal preserves concise state descriptions, derived methods, and pattern matching, while relaxing structural constraints that limit records.

By A N M Bazlur Rahman

Vercel Introduces Skills.sh, an Open Ecosystem for Agent Commands

Vercel has released Skills.sh, an open-source tool designed to provide AI agents with a standardized way to execute reusable actions, or skills, through the command line.

By Daniel Dominguez

Agent Trace: Cursor Proposes an Open Specification for AI Code Attribution

Cursor has published Agent Trace, a draft open specification aimed at standardizing how AI-generated code is attributed in software projects. Released as a Request for Comments (RFC), the proposal defines a vendor-neutral format for recording AI contributions alongside human authorship in version-controlled codebases.

By Robert Krzaczyński

Article: From Alert Fatigue to Agent-Assisted Intelligent Observability

As systems grow, observability becomes harder to maintain and incidents harder to diagnose. Agentic observability layers AI on existing tools, starting in read-only mode to detect anomalies and summarize issues. Over time, agents add context, correlate signals, and automate low-risk tasks. This approach frees engineers to focus on analysis and judgment.

By Rohit Dhawan

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