Working with threads

My aim was to creat e a program that performs the following:
o Create two threads
o One thread asks the user to enter groups of 5 numbers
o As soon as 5 numbers has been entered, the other thread computes it sum
o This continues for each group until the end of input is reached

I wrote the following code but itsd just not running, I guess I have not been able to codea good logic for them to synchronise please help!!!

Code java:

import java.io.BufferedReader;
import java.io.InputStreamReader;
 
 
public class Thrd1 implements Runnable {
	public static int wakeup()
	{
		return 1;
	}
	static int Numbers []= new int[5];
	int counter=0;
	public void run()
	{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String temp=null;
		try
		{
		System.out.println("Enter 5 numbers:");
		for(int i=0;i<5;i++)
		{
		System.out.println("Enter "+(i+1)+" numner:");
		temp=br.readLine();
		Numbers[i]=Integer.parseInt(temp);
		}
			wakeup();
		}
		catch(Exception e)
		{
			System.out.println("Error:"+e.getMessage());
		}
 
		}
 
	}
 
public class Thrd2 implements Runnable {
	public static int wakeup()
	{
		return 1;
	}
	public void run()
	{
 
		int sum=0;
		System.out.println("The sum of numbers is:");
		for (int i=0;i<5;i++)
		{
			sum+=Thrd1.Numbers[i];
 
		}
		System.out.println("Sum is ="+sum);
		wakeup();
	}
 
 
	}
 
public class MainClass {
 
	public static void main(String[] args) {
		while (true) {
			Thrd1 obj1 = new Thrd1();
			Thread firstthread = new Thread(obj1, "1st Thread");
			Thrd2 obj2 = new Thrd2();
			Thread secondthread = new Thread(obj2, "2nd Thread");
			if (Thrd1.wakeup()==1)
			{
				try {
					firstthread.wait();
					secondthread.start();
				} catch (InterruptedException e) {
					e.printStackTrace();
				}
			}
			if (Thrd2.wakeup()==1)
			{
				try {
					firstthread.start();
					secondthread.wait();
				} catch (InterruptedException e) {
					e.printStackTrace();
				}
			}
		}
 
	}
}