2 threads, one for array input and other for sum of elements in the array

Hi,

I have two threads, one for an int array input and other for calculating the sum of the elements in the array. I am able to create the first thread which takes an int array but not the second one. Please help

The code is as follows:

import java.util.Scanner; class ArrayInput implements Runnable { int[] a=new int[100]; Scanner sc=new Scanner(System.in); int num; public int getLength() { System.out.println("Enter the number of elements you want in the array = "); int num=sc.nextInt(); return num; } public void run() { ArrayInput ai=new ArrayInput(); int len=ai.getLength(); System.out.println("Enter the elements in the array = "); for(int i=0;i<len;i++) { a[i]=sc.nextInt(); } try { for(int i=0;i<len;i++) { System.out.print (" "+a[i]); Thread.sleep(1000); } } catch(InterruptedException e) { System.out.println("Thread Interrupted"); } } } class ArraySum implements Runnable { ArrayInput ai=new ArrayInput(); int len=ai.getLength(); public void run() { try { int sum=0; for(int i=0;i<len;i++) { sum=sum+ai.a[i]; Thread.sleep(2000); } } catch(InterruptedException e) { System.out.println("Thread Interrupted"); } } } public class ArrayThread { public static void main(String[] args) { ArrayInput ai=new ArrayInput(); Thread t=new Thread(ai); t.start(); ArraySum as=new ArraySum(); Thread t1=new Thread(as); t1.start(); } }

Problem in hand is - you want to transfer information from one thread to another thread

If you want to transfer each number [ array element] of array individually then you can trying using Blocking Queue where your one thread places the array element on blocking queue .. then .. another thread takes that number from blocking queue and perform the summation. Hint - try to apply Producer Consumer thread pattern here [ using wait/notify or blocking queue] . Producer is the thread read number from console. Consumer thread is the thread doing summation.

If you want to transfer whole array at one go from one thread to another thread, probably you do not require any threads. Steps can be done sequentially.

Thank you!

I will give that a try and check.