Question about Methods

Question

I was wondering why i was not getting the right output. The program should give me..
Storing : 0
Checking Queue...
Printing: 0
Storing: 1
Checking Queue...
Printing:1
etc...
but instead all I get is...
Storing :0
Checking Queue..
Storing:1
Checking Queue...
etc..
Here is my Code:
import java.util.ArrayList;
public class Problem {
     public Storage storeMe = new Storage();
     public static void main(String[] args) {
          (new Thread(new Counter())).start();
          (new Thread(new Printer())).start();
class Storage {
     ArrayList<Integer> queue = new ArrayList<Integer>();
     public int value;
     public int getValue() {
          if (queue.size() > 0)
               return queue.remove(0);
          else
               return -1;
     public void storeValue(int newvalue) {
          value = newvalue;
          queue.add(value);
class Counter extends Problem implements Runnable {
     public void run() {
          int counter = 0;
          while (true) {
               synchronized (this) {
                    try {
                         this.wait(1000L);
                    } catch (Exception e) {
               System.out.println("Storing : " + counter );
               storeMe.storeValue(counter);
               counter++;
class Printer extends Problem implements Runnable {
     public void run() {
          while (true) {
               synchronized (this) {
                    try {
                         this.wait(1000L);
                    } catch (Exception e) {
               System.out.println("Checking Queue ...");
               int num = storeMe.getValue();
               if (num != -1)
                    System.out.println("Printing : " + num);
}I think the problem with my code is that in the Printer class, the storeMe.getValue() method is not updated. Or more accurately, the queue is not updated.
Can anyone shed some light on this matter?
thanks in advance..

Answer 1

thanks for that info.
this program worked fine using static variables and methods. But now I'm trying to do it without using static modifier with the exception of the main().
I tried checking if there was an update on queue in the Printer class by changing the code to this:
class Printer extends Problem implements Runnable {
     public void run() {
          while (true) {
               synchronized (this) {
                    try {
                         this.wait(1000L);
                    } catch (Exception e) {
               System.out.println("Checking Queue ...");
               int num = storeMe.queue.size();
                    System.out.println("Queue size: " + num);
}and I got this output:
Storing : 0
Checking Queue ...
Queue size: 0
Checking Queue ...
Queue size: 0
Storing : 1
So basically, when the Printer Class runs and tries the to get the value from the storage class, it can't because the value read was 0, there was no queue. Does this mean that I have created a wrong object of the Storage class? or is there another way to call that method without using the static modifier?
Specifically, How do I Try to call an instance of a method with its values still intact? Let's say I want My Printer Class to access the values inputted by the Counter Class in the Storage Class.