The Illusion of Simultaneity
We teach programming as a strictly linear sequence — one statement after another, one truth at a time — and then hand students machines with a dozen cores and programs with hundreds of threads. This page is the bridge…
Concurrency
Threads, shared state, and the modern toolbelt — the capstone after imperative and object-oriented programming.
The Shared Mutability Disaster
Concurrency bugs have a reputation for being mystical. They are not — they are the entirely predictable consequence of one combination: state that is shared between threads and state that mutates . Either alone is safe.…
The Concurrent Toolbelt
Raw new Thread(...) is concurrency's goto : legal, occasionally necessary, and almost never the right first move. Modern platforms provide a toolbelt of higher abstractions that manage the dangerous parts for you. This…
Concurrency Gaps: Lessons from Building a Real Language
The rest of this section teaches concurrency through Java's standard toolbelt. This page is a companion from the other direction: what actually goes wrong when a language's concurrency support is incomplete, drawn from…