Java 21, set to be released on September 19, 2023, introduces record patterns in switch blocks and expressions, marking a significant step towards supporting functional programming patterns in Java. This release, along with previous versions that introduced features like lambda expressions and sealed classes, allows Java to express algebraic data types and provides idiomatic ways of using them. The article also delves into type theory concepts such as the bottom type, top type, unit type, and boolean type. Additionally, it explains how Java’s record classes solve the issue of handling data types in a more efficient and structured manner, and introduces pattern matching as a feature that simplifies code for processing data based on its type.
https://wscp.dev/posts/tech/java-pattern-matching/