ZoekGetal.java

package hfdst4;
import java.util.*;

class ZoekGetal extends Thread {
    protected int startpositie;
    protected int eindpositie;
    protected int getal;
    protected int[] rij;
    protected ArrayList<Integer> resultaten;

    public ZoekGetal(int startpositie, int eindpositie, int getal, int[] rij, ArrayList<Integer> resultaten) {
        this.startpositie = startpositie;
        this.eindpositie = eindpositie;
        this.getal = getal;
        this.rij = rij;
        this.resultaten = resultaten;
    }

    public void run() {
        for(int i = this.startpositie; i < this.eindpositie; i++) {
            if(rij[i] == this.getal) {
                this.resultaten.add(i);
            }
            try {
                Thread.sleep(10);
            } catch(InterruptedException e) {}
        }
    }
}

class TestZoekGetal {
    public static void main(String[] args) {
        int aantalThreads = 8;
        int N = 1000;
        int m = 10;
        ZoekGetal[] z = new ZoekGetal[aantalThreads];
        ArrayList[] r = new ArrayList[aantalThreads];
        int[] a = maakRij(N, m);
        // added
        int interval = N/aantalThreads;
        //
        for(int i=0;i<z.length;i++) {
            r[i] = new ArrayList();
            // z[i] = new ZoekGetal(0, N, 3, a, r[i]);
            z[i] = new ZoekGetal(i*interval, (i+1)*interval, 3, a, r[i]); // added
        }
        for(int i=0;i<z.length;i++) {
            z[i].start();
        }
        // added
        /*
        boolean done = false;
        while(!done) {
            done = true;
            for (int i = 0; i < z.length; i++) {
                if (z[i].isAlive()) {
                    done = false;
                    break;
                }
            }
        }
        */
        // or
        for (ZoekGetal zoek : z) {
            try {
                zoek.join();
            } catch(InterruptedException e) {
                e.printStackTrace();
            }
        }
        //
        for(int i=0;i<z.length;i++){
            System.out.println(""+i+":"+r[i]);
        }
   }
   public static int[] maakRij(int n, int m){
       int[] r = new int[n];
       for(int i=0;i<r.length;i++){
           r[i] = (int)(m*Math.random());
       }
       return r;
   }
}