Java

Everything in Java

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  09/26/2026

  Java sealed interfaces and record patterns in a switch

  A switch over a sealed interface lets javac prove every case is handled. Record patterns, when guards, and why adding default quietly turns that off.

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  09/02/2026

  Grouping and summarizing a list in modern Java

  Collectors.groupingBy with a downstream collector replaces most of the loop-and-map code people still write - plus records, which remove the class that loop needed.