Difference between ArrayList and HashMap in Java
One of the most critical difference between HashMap and ArrayList class is that former is the implementation of the hash table while later is a dynamic array which can resize itself. The HashMap and ArrayList are two of the most popular classes from Java Collection framework. Though both are used to store objects but they are completely different on their implementation, working and usage. The main difference between ArrayList and HashMap is that ArrayList is index based data-structure backed by an array while HashMap is map data structure which works on hashing to retrieve stored values. This is also one of the frequently asked Java Collection interview questions, which is often asked Java developers of 1 to 3 years of experience. Apart from this fundamental difference between ArrayList and HashMap, there are many other differences, which we will see in this Java tutorial. But before that let's see some similarity between ArrayList and HashMap in Java.
One of the most critical difference between HashMap and ArrayList class is that former is the implementation of the hash table while later is a dynamic array which can resize itself. The HashMap and ArrayList are two of the most popular classes from Java Collection framework. Though both are used to store objects but they are completely different on their implementation, working and usage. The main difference between ArrayList and HashMap is that ArrayList is index based data-structure backed by an array while HashMap is map data structure which works on hashing to retrieve stored values. This is also one of the frequently asked Java Collection interview questions, which is often asked Java developers of 1 to 3 years of experience. Apart from this fundamental difference between ArrayList and HashMap, there are many other differences, which we will see in this Java tutorial. But before that let's see some similarity between ArrayList and HashMap in Java.
