Java Architect Essentials

Jun 10, 2023 · Fundamentals

Why List.contains Is So Slow for Java Deduplication – Benchmark Results

This article benchmarks several Java deduplication techniques—including List.contains, HashSet, double-loop removal, and Stream.distinct—using a 20,000‑element list, analyzes their execution times, explains underlying time complexities, and provides practical recommendations on which method to use.