Runtime
The Cost of Optional
Identical source, five call sites, one JDK 26 run - nothing allocated at the first and twelve bytes at three others. The wrapper is not what decides.
Topic
java
Articles on “java”
Diagnostics
Reading a Thread Dump Without Guessing
A thread dump answers precise questions if you ask them precisely. What each state really means, and the traps that produce confident wrong diagnoses.
Concurrency
Virtual Threads and the Pinning Problem
Virtual threads scale until something nails one to its carrier. Here is what still pins on modern JDKs, and how to see it happen.