unknown

The Singleton pattern is often implemented incorrectly with thread-safety issues or unnecessary complexity. Common anti-patterns include broken lazy initialization (not thread-safe), eager initialization (slows startup), and over-engineered double-checked locking. The two professional approaches are the Bill Pugh Holder Idiom (lazy, thread-safe, simple) and Enum Singletons (bulletproof against reflection and serialization issues). True seniority means choosing the simplest solution that works, depending on interfaces rather than concrete implementations for testability, and avoiding over-engineering driven by ego.

The Singleton Delusion: Why Your Implementation is Probably Broken

All Java, All the time.

Newcomers to veterans, all are welcome to post and comment about anything Java related. Love it, hate it - all topics are safe here. 

Just Java

Stop using 50MB frameworks to manage one single instance of a Logger.


Most developers think they know how to write a Singleton. They read a blog post a decade ago and haven't checked if that information is still valid for the modern JVM. The result? Production code filled with thread-safety issues, memory leaks, and "Senior" implementations that are actually maintenance liabilities.


We’ve moved from "Singletons everywhere" to "DI frameworks for everything," but we’ve forgotten how to actually use the JVM.


In my latest post, I break down:

- The Reality of Failure: Why "Double-Checked Locking" is often just a sophisticated way to introduce bugs.

- The "Resume-Driven Development" Trap: Why we over-engineer simple patterns just to look smart.

- The 2026 Standard: Why the Enum Singleton remains the only truly bulletproof implementation.

- Testing Myths: Why "Singletons are hard to test" is usually a symptom of poor interface design, not the pattern itself.


Complexity is debt. Every line of extra code is something that can break at 3 AM. If you’re still writing ten lines of synchronized boilerplate for a task that requires one, you're building a liability, not a feature.

Stop using 50MB frameworks to manage one single instance of a Logger.


Most developers think they know how to write a Singleton. They read a blog post a decade ago and haven't checked if that information is still valid for the modern JVM. The result? Production code filled with thread-safety issues, memory leaks, and &quot;Senior&quot; implementations that are actually maintenance liabilities.


We’ve moved from &quot;Singletons everywhere&quot; to &quot;DI frameworks for everything,&quot; but we’ve forgotten how to actually use the JVM.


In my latest post, I break down:

- The Reality of Failure: Why &quot;Double-Checked Locking&quot; is often just a sophisticated way to introduce bugs.

- The &quot;Resume-Driven Development&quot; Trap: Why we over-engineer simple patterns just to look smart.

- The 2026 Standard: Why the Enum Singleton remains the only truly bulletproof implementation.

- Testing Myths: Why &quot;Singletons are hard to test&quot; is usually a symptom of poor interface design, not the pattern itself.


Complexity is debt. Every line of extra code is something that can break at 3 AM. If you’re still writing ten lines of synchronized boilerplate for a task that requires one, you're building a liability, not a feature.

Just don’t do statefull programming and you won’t need them.

Nice, clean, simple and efficently uses the tools that the JVM gives you. 🙂
What else could one want? That Iberian ham looks delicious (reminds me of our trip to Barcelona). Now I’m hungry. 😆

KISS — Keep It Simple and Stupid!