20+ Array-Based Coding Problems for programmers ( list).More Java and Data Structure Interview Questions you may like Programming questions from various Interviews : If you like this article and would like to try out a couple of moreĬhallenging programming exercises, then take a look at the following I have used the Hashtable class as a representative of hash table data structure in Java but you can put HashMap, ConcurrentHashMap or any other Map implementation in place of Hashtable and most of the differences will be valid. That's all about the difference between array and hash table data structure in Java. both provide fast search performance when a search is by key or index. hashtable is internally backed by an arrayģ. Now that we have seen some differences between array and hash table data structure, now let's see some similarities.Ģ. The array is not synchronized and cannot be made synchronized but Hashtable is synchronized in Java. There is a collision in the array but collision is possible in the hash table For example, in Java, we have Hashtable and HashMap classes in java.util package which is our general-purpose hash table data structure requires key objects to implement equals() and hashcode() method. Hash table data structure is also known as dictionary in Python and Map in many other programming languages.Īrray stores just one object but the hash table stores mapping, I mean pair of key and value objects.Īrray doesn't enforce any requirement on storing objects but hash tables usually require the key object to implement some interface so that it can calculate hash values. Most of the differences are also valid for general array vs hash table data structure in computer science programming. Let's now compare array in Java with the Hashtable or HashMap class in Java. In this article, you will learn about both structural and performance differences between array and hashtable in Java. It also uses a linked list and binary tree data structure to deal with collision and maintain acceptable performance. Yes, a Hashtable or HashMap is also backed by an array, but that's not the full story. constant time search operation also known as O(1) search, the fundamental difference between them is that array require an index while hash table requires a key which could be another object.Īctually, the hash table is an extension of the array where the hash function is used to convert the key into an index required by the array, which is further used to locate the element in the internal array. Even though both array and hashtable data structure are intended for fast search i.e. A couple of days back someone asked me about the difference between an array and a hashtable, though this is a generic data structure and programming question, I'll answer it from both a general programming perspective as well on Java perspective where Hashtable is not just a data structure but also a class from Java Collection API.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |