import java.util.concurrent.ForkJoinPool;
import java.util.concurrent.RecursiveAction;

public class ForkJoin {

    public static void main(String[] args) {
        byte a[] = new byte[256];
        byte b[] = new byte[256];

        // a, b代入

        ForkJoinPool pool = new ForkJoinPool();
        pool.invoke(new MyAction(a, b, 0, a.length - 1));
    }

    private static class MyAction extends RecursiveAction {
        private static final long serialVersionUID = 1L;

        private final byte a[];
        private final byte b[];
        private final int start;
        private final int end;

        MyAction(byte a[], byte b[], int start, int end) {
            this.a = a;
            this.b = b;
            this.start = start;
            this.end = end;
        }

        @Override
        protected void compute() {
            if (end - start == 0) {
                a[start] &= b[start];
            } else {
                invokeAll(new MyAction(a, b, start, start + (end - start) / 2),
                        new MyAction(a, b, start + (end - start) / 2 + 1, end));
            }
        }
    }
}