ArrayList methods in Java

1) You can define ArrayList as re-sizable array. Size of the ArrayList is not fixed. ArrayList can grow and shrink dynamically . 2) Elements can be inserted at or deleted from a particular position.

ArrayList internally uses a dynamic array to store its elements. LinkedList uses Doubly Linked List to store its elements . ArrayList is slow as array manipulation is slower. LinkedList is faster being node based as not much bit shifting required.

Array is a fixed length data structure whereas ArrayList is a variable length Collection class . We cannot change length of array once created in Java but ArrayList can be changed.

Base 1: An array is a basic functionality provided by Java. ArrayList is part of the collection framework in Java. Therefore array members are accessed using [], while ArrayList has a set of methods to access elements and modify them .