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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.


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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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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…
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Created by Michael Levin Dec 18, 2008 at 6:56pm. Last updated by Michael Levin May 4, 2018.

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InfoQ Reading List

Inside the Development Workflow of Claude Code's Creator

Claude Code's creator Boris Cherny described how he uses it at Anthropic, highlighting practices such as running parallel instances, sharing learnings, automating prompting, and rigorously verifying results to compound productivity over time.

By Sergio De Simone

NVIDIA Releases Open Models, Datasets, and Tools Across AI, Robotics, and Autonomous Driving

NVIDIA has released a set of open models, datasets, and development tools covering language, agentic systems, robotics, autonomous driving, and biomedical research. The update expands several existing NVIDIA model families and makes accompanying training data and reference implementations available through GitHub, Hugging Face, and NVIDIA’s developer platforms.

By Robert Krzaczyński

MongoBleed Vulnerability Allows Attackers to Read Data From MongoDB's Heap Memory

MongoDB recently patched CVE-2025-14847, a vulnerability affecting multiple supported and legacy MongoDB Server versions. According to the disclosure, the flaw can be exploited remotely by unauthenticated attackers with low complexity, potentially leading to the exfiltration of sensitive data and credentials.

By Renato Losio

Presentation: Fast Eventual Consistency: Inside Corrosion, the Distributed System Powering Fly.io

Somtochi Onyekwere explains the architecture of Corrosion, a distributed system designed for low-latency state replication. She shares how Fly.io transitioned from Consul to a gossip-based SQLite solution to handle global machine data. By discussing CRDTs, the SWIM protocol, and QUIC, she shares how to build resilient systems that prioritize speed while managing the complexities of CAP theorem.

By Somtochi Onyekwere

Mini book: The InfoQ Trends Reports 2025 eMag

This special edition of The InfoQ eMag, contains a comprehensive collection of our popular InfoQ Trends Reports from 2025, a year with both evolution and revolution within the landscapes of technology, software development trends. This collection does not just reflect the past year's technological trends. We aspire to use it as a guide for future exploration and innovation.

By InfoQ

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