Java Memory Model (JMM)

Java Memory Model (JMM)

From Programmers by Software Engineering

January 22, 2026 · 29 min

About this episode

This episode explores the concept of Happens-Before in the Java Memory Model and its implications for multi-threaded programming.

RexIDE - https://rex.mindmeld360.com We explore the fundamental concept of Happens-Before (HB) —not a measure of time, but a formal mathematical relationship that provides the only real guarantee of visibility and ordering in a multi-threaded world. Without an HB edge, your threads are effectively living in different realities, where one thread might see an object has been published but observe its internal fields as stale or uninitialized zeros.

Topics covered

  • Java Memory Model
  • Happens-Before
  • multi-threading
  • visibility
  • ordering

Mentioned in this episode

Products: RexIDE

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