A practical guide to correctly implementing Java's hashCode method. Covers the hashCode contract, why it must be overridden whenever equals is overridden, and how to choose the right fields. Discusses trade-offs between performance and collision avoidance, warns against using mutable fields, and recommends using Objects.hash() or a prime-multiplication algorithm. Includes tips on avoiding common pitfalls like always returning 0 or including collection fields unnecessarily.
Table of contents
▚ Equality and Hash Code▚ Thoughts on Hashing▚ The hashCode Contract▚ Implementing hashCode▚ SummarySort: