List Interface in Java

List Interface in Java

The List interface is found in java.util package and inherits the Collection interface. It is a factory of the ListIterator interface. Through the ListIterator, we can iterate the list in forward and backward directions. The implementation classes of the List interface are ArrayList, LinkedList, Stack, and Vector. ArrayList and LinkedList are widely used in Java programming. The Vector class is deprecated since Java 5....

Declaration of Java List Interface

public interface List extends Collection ;...

Example of Java List

Java // Java program to Demonstrate List Interface    // Importing all utility classes import java.util.*;    // Main class // ListDemo class class GFG {        // Main driver method     public static void main(String[] args)     {            // Creating an object of List interface         // implemented by the ArrayList class         List l1 = new ArrayList();            // Adding elements to object of List interface         // Custom inputs            l1.add(0, 1);         l1.add(1, 2);            // Print the elements inside the object         System.out.println(l1);            // Now creating another object of the List         // interface implemented ArrayList class         // Declaring object of integer type         List l2 = new ArrayList();            // Again adding elements to object of List interface         // Custom inputs         l2.add(1);         l2.add(2);         l2.add(3);            // Will add list l2 from 1 index         l1.addAll(1, l2);            System.out.println(l1);            // Removes element from index 1         l1.remove(1);            // Printing the updated List 1         System.out.println(l1);            // Prints element at index 3 in list 1         // using get() method         System.out.println(l1.get(3));            // Replace 0th element with 5         // in List 1         l1.set(0, 5);            // Again printing the updated List 1         System.out.println(l1);     } }...

Operations in a Java List Interface

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Complexity of List Interface in Java

Since List is an interface, it can be used only with a class that implements this interface. Now, let’s see how to perform a few frequently used operations on the List....

Iterating over List Interface in Java

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Methods of the List Interface

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Java List vs Set

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