0

I have a program that uses two threads, one that adds some numbers and the other takes the sum and finds the average. I used a blocking queue to pass the sum to the other string. I have no problem queue.put() to put the total in the queue and then using queue.take() to take it out and print it. What I need to do though is when taking the total out of the queue is to save it to a variable so I can calculate the average with it. Can someone tell me if I am able to do this with queue.take() or if i have to use some other way. When attempt to save it to the sum variable which is an int I get the error

incompatible types
int sum = queue.take();
^

required: int
found: Object.

My code is below

import java.util.concurrent.*;
import java.util.*;
import java.util.Scanner;
class Producer implements Runnable{

    protected BlockingQueue queue = null;

    public Producer(BlockingQueue queue) {
        this.queue = queue;
    }

    public void run() {
        try {
		    Scanner input = new Scanner(System.in);
			int total = 0;
			int grade;
			int average;
			int counter = 0;
			
			while (counter < 5){
			    System.out.println("Enter number: ");
				grade = input.nextInt();
				total = total + grade;
				counter++;
			}
			
			queue.put(total);
            Thread.sleep(1000);
           
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
} 

class Consumer implements Runnable{

    protected BlockingQueue queue = null;

    public Consumer(BlockingQueue queue) {
        this.queue = queue;
    }

    public void run() {
        try {
		    
			//System.out.println(queue.take());
			int sum = queue.take();
			System.out.println("The sum is "+sum);
            
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

public class apples {

    public static void main(String[] args) throws Exception {

       // BlockingQueue queue = new ArrayBlockingQueue<string>(1024);
		BlockingQueue queue = new ArrayBlockingQueue(1024);

        Producer producer = new Producer(queue);
        Consumer consumer = new Consumer(queue);

        new Thread(producer).start();
        new Thread(consumer).start();

        Thread.sleep(4000);
    }
}
2
Contributors
1
Reply
2
Views
6 Years
Discussion Span
Last Post by JamesCherrill
0

You define a BlockingQueue without specifying what kind of Objects can go in the Queue, so it defaults to any Object. You add an int, and the compiler kindly converts that to an Integer for you. But when you try to take things from the queue all that Java knows is that the queue can contain any kind of Object, so it says it can't convert that to int (quite rightly).
If you replace every BlockingQueue with a BlockingQueue<Integer> then the compiler will know that only Integer values can go into the queue, so Integers came come out, the compiler will know how to deal with those, and all will be fine.

This topic has been dead for over six months. Start a new discussion instead.
Have something to contribute to this discussion? Please be thoughtful, detailed and courteous, and be sure to adhere to our posting rules.