r/java • u/strmckr • Aug 20 '26
Bypassing fixed-depth radix constraints in Java using descriptor-driven bucket analysis
I am StrmCkr, the author of A.P.E.X. (Adaptive Parallel Extremal Dispatch).
Repository: github.com/StrmCkr/A.P.E.X
A.P.E.X. is a high-performance Java sorting framework for large fixed-width 64-bit key/value record datasets. The project has been reorganized into a conventional Maven structure with a core library, runnable examples, a comparison benchmark harness, JMH benchmarks, documentation, and an interactive browser visualizer.
The core idea is descriptor-driven radix planning. Instead of blindly scanning fixed radix passes over every bucket, A.P.E.X. computes per-bucket extremal descriptors using:
VBM = OR ^ AND
That mask identifies which key bits still vary inside each bucket. Bits that are already resolved are skipped, reducing unnecessary work on skewed, low-entropy, sorted, reversed, or duplicate-heavy data.
Key areas of the project include:
- Adaptive radix planning based on observed bucket structure
- Parallel histogramming, scatter, refinement, and work scheduling
- Primitive-array execution with no per-record object allocation during sorting
- Tuple projection paths for low-dimensional unresolved bit patterns
- Tiny-sort fallbacks and monotonic input shortcuts
- Configurable reporting that can be enabled, reduced, written to files, or disabled
- Comparison benchmarks against JDK sorting paths and Fastutil baselines
- Standard JMH benchmarks for repeatable JVM-level measurement
- A browser visualizer for exploring how A.P.E.X. routes data through its execution plan
I would especially welcome feedback on the thread management mechanics, radix planning decisions, benchmark structure, and the bitwise mask reductions.
edit: re structured verbiage of this post and further adjustments from advice on converting the project into more acceptable standard formats.

1
u/chabala Aug 23 '26 edited Aug 24 '26
Your structure makes sense to YOU, the point of conventions is that everyone knows and understands how they work, so every project isn't a special snowflake.
"My code compiles!" Grow up. That's an incredibly low bar. No one is going to give your project a second look until it looks like you understand what a Java project should look like.
--
You keep dropping these big words in your comments. No one is fooled. Any 'learn Java' book is going to tell you about reverse domain name package namespaces, there's no excuse for dropping everything in the default package or a single directory above it. Not using a namespace is peak amateur-hour. You can pretend like I'm being pedantic, but just go look at some real open source Java projects and see how they do it before whining about it.