“Cannot instantiate the type…”

Question

When I try to run this code:

import java.io.*;
import java.util.*;

public class TwoColor
{
    public static void main(String[] args) 
    {
         Queue&         


        

Answer 1

Queue is an Interface so you can not initiate it directly. Initiate it by one of its implementing classes.

From the docs all known implementing classes:

• AbstractQueue
• ArrayBlockingQueue
• ArrayDeque
• ConcurrentLinkedQueue
• DelayQueue
• LinkedBlockingDeque
• LinkedBlockingQueue
• LinkedList
• PriorityBlockingQueue
• PriorityQueue
• SynchronousQueue

You can use any of above based on your requirement to initiate a Queue object.