Search icon CANCEL
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
Concurrent Patterns and Best Practices

You're reading from   Concurrent Patterns and Best Practices Build scalable apps in Java with multithreading, synchronization and functional programming patterns

Arrow left icon
Product type Paperback
Published in Sep 2018
Publisher Packt
ISBN-13 9781788627900
Length 264 pages
Edition 1st Edition
Languages
Concepts
Arrow right icon
Author (1):
Arrow left icon
Atul S. Khot Atul S. Khot
Author Profile Icon Atul S. Khot
Atul S. Khot
Arrow right icon
View More author details
Toc

Concurrent hashing

 A hash table is typically implemented as an array. Each array entry is a list of one or more items. A hash function maps values to indices in this array. Each Java object has a hashCode() method that gives an integer for an object. This number's modulo to the array length gives us an index into this array.

For any operation to add, remove, or check whether the set contains an item, we first index into the array (or table), and then perform the rest of the processing.

The basic idea is that, given a table and a hash function, we provide the contains(key), add(key, value), and remove(key) methods, with a constant average time.  

The following diagram shows how a typical hash table works:

The key is run through a hash function (f()). The resulting modulo of the hash function...

lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at $19.99/month. Cancel anytime