Java : Thread / callable example : to find out the max integer

FindMaxTask.java

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package neo.util;

import java.util.concurrent.Callable;

/**
 *
 * @author neojou
 */
class FindMaxTask implements Callable<Integer> {
    
    private int data[];
    private int start;
    private int end;
    
    FindMaxTask(int data[], int start, int end) {
        this.data = data;
        this.start = start;
        this.end = end;
    }
    
    public Integer call() {
        int max = Integer.MIN_VALUE;
        
        for (int i=start; i<end; i++) {
            if (data[i]>max) max = data[i];
        }
        return max;
    }
    
}

MultiThreadMaxFinder.java

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package neo.util;

import java.util.concurrent.*;



/**
 *
 * @author neojou
 */
public class MultiThreadMaxFinder {

    public static int max(int[] data) throws InterruptedException, ExecutionException {
        if ( data.length == 1 ) return data[0];
        else if ( data.length == 0 ) throw new IllegalArgumentException();
        
        FindMaxTask task1 = new FindMaxTask(data, 0, data.length/2);
        FindMaxTask task2 = new FindMaxTask(data, data.length/2, data.length);
        
        ExecutorService service = Executors.newFixedThreadPool(2);
        
        Future<Integer> future1 = service.submit(task1);
        Future<Integer> future2 = service.submit(task2);
        
        return Math.max(future1.get(), future2.get());
        
    }
    
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        int[] a = { 1, 10, 2, 3, 5, 8, 4, 6, 9 };
        
        for (int i=0; i<a.length; i++)
            System.out.println(a[i]);
        
        System.out.print("Max number:");
        try { 
            System.out.println(MultiThreadMaxFinder.max(a));
        } catch ( Exception e) {
            e.printStackTrace();
        }
        
    }
    
}