record-patterns.yaml

---
id: 7
slug: "record-patterns"
title: "Record patterns (destructuring)"
category: "language"
difficulty: "intermediate"
jdkVersion: "21"
oldLabel: "Java 8"
modernLabel: "Java 21+"
oldApproach: "Manual Access"
modernApproach: "Destructuring"
oldCode: |-
  if (obj instanceof Point) {
      Point p = (Point) obj;
      int x = p.getX();
      int y = p.getY();
      System.out.println(x + y);
  }
modernCode: |-
  if (obj instanceof Point(int x, int y)) {
      IO.println(x + y);
  }
summary: "Destructure records directly in patterns — extract fields in one step."
explanation: "Record patterns let you decompose a record's components directly in\
  \ instanceof and switch. Nested patterns are supported too, enabling deep matching\
  \ without intermediate variables."
whyModernWins:
- icon: "🎯"
  title: "Direct extraction"
  desc: "Access record components without calling accessors manually."
- icon: "🪆"
  title: "Nestable"
  desc: "Patterns can nest — match inner records in a single expression."
- icon: "📏"
  title: "Compact code"
  desc: "Five lines become two — less ceremony, same clarity."
support:
  state: "available"
  description: "Widely available since JDK 21 LTS (Sept 2023)"
prev: "language/sealed-classes"
next: "language/unnamed-variables"
related:
- "language/diamond-operator"
- "language/records-for-data-classes"
- "language/unnamed-variables"
docs:
- title: "Record Patterns (JEP 440)"
  href: "https://openjdk.org/jeps/440"