# On Generating Identity Hash Codes

DevFeed: [On Generating Identity Hash Codes](<https://devfeed.tech/articles/on-generating-identity-hash-codes-24843.md>)

Original publisher: [Read original article](<https://alidg.me/blog/2020/7/15/hash-code>)

Author: Alimate

Published: 2020-07-15T00:00:00Z

Content type: tutorial

Language: en

Sources: [Ali Dehghan - Kemikit](<https://devfeed.tech/sources/ali-dehghan-kemikit.md>)

Topics: [Java](<https://devfeed.tech/topics/java.md>), [Randomizer](<https://devfeed.tech/topics/randomizer.md>), [Algorithms, Complexity](<https://devfeed.tech/topics/algorithms-complexity.md>), [Concurrency](<https://devfeed.tech/topics/concurrency.md>), [Benchmark](<https://devfeed.tech/topics/benchmark.md>)

Tags: [algorithm](<https://devfeed.tech/tags/algorithm.md>), [benchmark](<https://devfeed.tech/tags/benchmark.md>), [cas](<https://devfeed.tech/tags/cas.md>), [generate](<https://devfeed.tech/tags/generate.md>), [hash](<https://devfeed.tech/tags/hash.md>), [java](<https://devfeed.tech/tags/java.md>), [jvm](<https://devfeed.tech/tags/jvm.md>), [memory](<https://devfeed.tech/tags/memory.md>), [retry](<https://devfeed.tech/tags/retry.md>), [threads](<https://devfeed.tech/tags/threads.md>)

## AI overview

This tutorial explains how the HotSpot JVM generates identity hash codes in Java. It examines several strategies, including Park-Miller/Lehmer random number generation, memory-address-based values, a constant value, and sequential numbers, while discussing atomic updates and contention.

## Source excerpt

Have you ever wondered how does the HotSpot JVM generate identity hashcodes?