Java take() Method of LinkedBlockingQueue is stuck, even if the Queue should not be empty

Question

I'm writing Code for a Network Application. Therefor I'm using a LinkedBlockingQueue to store incoming messaged until they are consumed. The following code runs in it's own Thread and fills up the Queue:

while(true) {
    String msg = in.readLine();
    if(msg == null) continue;
    recieveQueue.offer(msg);
    System.out.println("recieveQueue.offer() called at: " + System.currentTimeMillis() + "    hash:" + recieveQueue.hashCode());
    System.out.println("Server recieved: " + msg.replace("\n", ""));
    break;
}

Next I wrote a Method, which runs in the same "Main-Thread" (No extra Thread is created for this Method). It's only called when the stored Elements have to be consumed. It looks like the following:

public String recieveMessage() {
    try {
        System.out.println("recieveQueue.take() called at: " + System.currentTimeMillis() + "    hash:" + recieveQueue.hashCode());
        return recieveQueue.take();
    }catch(InterruptedException e) {
        e.printStackTrace();
        return null;
    }
}

When running this Code I get the following output:

recieveQueue.offer() called at: 1594558123030    hash:2091496189
Server recieved: CONFIRMED
recieveQueue.take() called at: 1594558123031    hash:2091496189

The hash verifies that I'm working on the same Queue, and as seen by the Time, recieveQueue.offer(msg) is definitely called before take() and so the Queue should contain a message. But the Program stops at the take() call. No Exceptions were thrown and there is no other point in the code where take() gets called. I waited for like 10 minutes but the take() call never finishes

Answer 1

Made few changes in your program.

Note: Please check in your code Consumer in while loop.

import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.BlockingQueue;

public class Main
{
    public static void main(String[] args) {
    BlockingQueue recieveQueue = new LinkedBlockingQueue<String>(10);
    
    new Thread(){
       public void run(){
       int count=0;
          while(true) {
                    count++;
                    String msg = "AAA:"+count;
                    if(msg == null) continue;
                    recieveQueue.offer(msg);
                    System.out.println("recieveQueue.offer() called at: " + System.currentTimeMillis() + "    hash:" + recieveQueue.hashCode());
                    System.out.println("Server recieved: " + msg.replace("\n", ""));
          }
       } 
    }.start();
    
    while(true){
        try {
            System.out.println("recieveQueue.take() called at: " + System.currentTimeMillis() + "    hash:" + recieveQueue.hashCode());
            System.out.println("recieveQueue.take() : "+recieveQueue.take());
        }catch(InterruptedException e) {
            e.printStackTrace();
        }
    }
    
    
 }
}