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JavaSpecialists

Issue 337 - Module Imports

Module imports are a new feature in Java 25 and are like a wildcard import for *all* the types in a module. If you hate wildcard imports, you'll despise this even more. But if, like me, you don't really care whether someone uses a wildcard or single-type import, this is for you.

Issue 336 - CopyOnWriteArrayList.subList() ConcurrentModificationException

Java's CopyOnWriteArrayList gives us a snapshot iterator for fast reading. However, its subList() is not snapshot, and will break if the list is changed. In this newsletter we look at a way to make a safe subList() copy, using the iterator and an AbstractList.

Issue 335 - ZGC Mysteries

In our previous newsletter we posted a puzzle about ArrayList creation in ZGC. Lots of Java programmers sent in their ideas, and we are still looking for the perfect answer. Here are some more thoughts on the idea, whilst we wait for The Z Garbage Collector Book to arrive.

Issue 334 - ArrayList vs LinkedList Puzzle

Every schoolboy knows that arrays are faster than linked structures, no matter the language. In this newsletter we present a puzzle where we find LinkedList outperforming ArrayList for ZGC. Let's see who comes up with the most thorough explanation why.

Issue 333 - Surprising += Cast (Rerun)

Surprisingly, the compound arithmetic expression contains a cast that can produce some interesting side effects. In this newsletter we explore this and other edge cases in the Java Language Specification.


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Blog Posts

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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JavaFX and SteelSeries gauges using FXML

Posted by Jim Clarke on June 25, 2012 at 9:30pm 0 Comments

Gerrit Grunwald, aka @hansolo_ on twitter, has just ported his Swing based gauges and meters framework known as SteelSeries to JavaFX as part of the JFXtras-lab project. I can't tell you how many times since Java AWT first came out, that I have had to use meters…

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Ceylon OJUG & GatorJUG Talk - Please Yo me!

Posted by Michael Levin on June 27, 2014 at 11:15am 4 Comments

Dear Codetown JUGGIES:

We have a chance for a special Ceylon talk on either Mon 10/13, Fri 10/17, Mon 10/20, or Fri 10/24 in Orlando at OrlandoJUG and/or Gainesville at GatorJUG. 

As you all know, OJUG meets 4th Th and GatorJUG meets 2nd Wed and these are Mondays and Fridays, so I need your…

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What's bit.ly?

Posted by Michael Levin on March 22, 2009 at 12:00pm 0 Comments

On the surface, bit.ly appears to be a tinyurl.com clone. But, bit.ly has a powerful API so you can use it in your websites. It also has semantic capability and uses Amazon S3 to store your data. It's GeoSpatially enabled, which raises all sorts of possibilities. Think iPhone apps - especially with iPhone 3G's GPS capability. Here's a good… Continue

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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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I recently read an article describing how to pair an Apple Watch with an iPhone. Looks great. You can leave your iPhone someplace and then use your Apple Watch as a phone. I don’t know anything about Apple watches, but they have them at Costco and of course at the Apple Store. What’s the latest, best one to get And Ann what do you know about this idea?…See More
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Apple Watch paired with iPhone

I recently read an article describing how to pair an Apple Watch with an iPhone. Looks great. You can leave your iPhone someplace and then use your Apple Watch as a phone. I don’t know anything about Apple watches, but they have them at Costco and of course at the Apple Store. What’s the latest, best one to get And Ann what do you know about this idea?…See More
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#devwithserdar With hardware prices spiraling, AI vendors ramping up token costs, and models becoming drastically slimmer and more economical, running AI mod...
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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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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

Backstage 1.55 Adds Scaffolder Task Recovery and Removes Deprecated Catalog APIs

Backstage 1.55 adds opt-in recovery for Software Template tasks, resuming crashed or timed-out runs from the last completed step. The release also carries breaking changes to the catalog, search and TechDocs, so teams should review their configuration before upgrading to the current 1.55.3 patch.

By Mark Silvester

ZCS Command Injection via SNMP Handlers Enables Unauthenticated Remote Code Execution

A critical remote command execution vulnerability in the Zimbra Collaboration Suite, identified as CVE-2026-73570, poses risks by allowing unauthorized access to mailbox data and credentials. This flaw, stemming from improper input sanitization, has been actively exploited. Organizations are advised to upgrade to version 10.1.20 or disable susceptible SNMP services to mitigate risks.

By Olimpiu Pop

AWS Reworks EventBridge Custom Buses for Enterprise-Scale Event-Driven Architectures

AWS has introduced an enhanced Custom Event Bus for Amazon EventBridge, targeting a problem that often emerges when event-driven architectures move beyond a single team or AWS account: the event infrastructure itself becomes fragmented.

By Craig Risi

Production Patterns for Agents, Evals, and LLM Costs: QCon AI New York 2026

Once AI is in production, code arrives faster than it can be reviewed, token costs rise, evals have to be good enough to act on, and agents need permissions and guardrails. QCon AI New York 2026 (December 15-16) has confirmed sessions from engineers sharing how they handle these constraints.

By Artenisa Chatziou

Presentation: How Eve Online Leverages Head Based Sampling to Observe "Fun"

Nicholas Herring shares how EVE Online tackles distributed tracing and observability across a 20-year-old MMO architecture. He discusses leveraging head-based, dynamic exponential moving average (EMA), and deterministic sampling techniques to maintain high system fidelity, control telemetry costs, and avoid performance degradation under high-throughput real-time game simulations.

By Nicholas Herring

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