Difference Between ArrayList and LinkedList
ArrayList and LinkedList both implement the List interface and maintain insertion order. Both are non-synchronized classes.
However, there are many differences between the ArrayList and LinkedList classes that are given below.
ArrayListLinkedList
1) ArrayList internally uses a
dynamic array
to store the elements.LinkedList internally uses a
doubly linked list
to store the elements.
2) Manipulation with ArrayList is
slow
because it internally uses an array. If any element is removed from the array, all the other elements are shifted in memory.Manipulation with LinkedList is
faster
than ArrayList because it uses a doubly linked list, so no bit shifting is required in memory.
3) An ArrayList class can
act as a list
only because it implements List only.LinkedList class can
act as a list and queue
both because it implements List and Deque interfaces.
4) ArrayList is
better for storing and accessing
data.LinkedList is
better for manipulating
data.
5) The memory location for the elements of an ArrayList is contiguous.The location for the elements of a linked list is not contagious.
6) Generally, when an ArrayList is initialized, a default capacity of 10 is assigned to the ArrayList.There is no case of default capacity in a LinkedList. In LinkedList, an empty list is created when a LinkedList is initialized.
7) To be precise, an ArrayList is a resizable array.LinkedList implements the doubly linked list of the list interface.
Example of ArrayList and LinkedList in Java
Let's see a simple example where we are using ArrayList and LinkedList both.
FileName:
TestArrayLinked.java
import java.util.*;
class TestArrayLinked{
public static void main(String args[]){
List
al=new ArrayList
();//creating arraylist
al.add("Ravi");//adding object in arraylist
al.add("Vijay");
al.add("Ravi");
al.add("Ajay");
List
al2=new LinkedList
();//creating linkedlist
al2.add("James");//adding object in linkedlist
al2.add("Serena");
al2.add("Swati");
al2.add("Junaid");
System.out.println("arraylist: "+al);
System.out.println("linkedlist: "+al2);
Test it Now
Output:
arraylist: [Ravi,Vijay,Ravi,Ajay]
linkedlist: [James,Serena,Swati,Junaid]
Points to Remember
The following are some important points to remember regarding an ArrayList and LinkedList.
When the rate of addition or removal rate is more than the read scenarios, then go for the LinkedList. On the other hand, when the frequency of the read scenarios is more than the addition or removal rate, then ArrayList takes precedence over LinkedList.
Since the elements of an ArrayList are stored more compact as compared to a LinkedList; therefore, the ArrayList is more cache-friendly as compared to the LinkedList. Thus, chances for the cache miss are less in an ArrayList as compared to a LinkedList. Generally, it is considered that a LinkedList is poor in cache-locality.
Memory overhead in the LinkedList is more as compared to the ArrayList. It is because, in a LinkedList, we have two extra links (next and previous) as it is required to store the address of the previous and the next nodes, and these links consume extra space. Such links are not present in an ArrayList.
Next TopicListIterator in Java Collection
← prev
next →
