a Java Class which scans ports in an IP

I had to run port scanner software for security check reason, before deliver the product. I tried to get one utilillity from internet. but, the Websites were blocked in my company to download. so, I just made a Java Class which can do the port scanning. it takes around 20 min to run throught all the ports. If I increase Thread size and shorten the timeout, it will take less then 5 min.

Fornow, I have a little problem. When I let it run quickly, Firewall or security software get activated and deny to response if the port is opened. So, I had to let it run slowly to find all the opened port.

package com.devtrigger;

import java.net.InetSocketAddress;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;

class PortScanner {

    public static void main(final String... args) throws InterruptedException, ExecutionException {
        final ExecutorService es = Executors.newFixedThreadPool(15);

        final String ip = "127.0.0.1";

        final int timeout = 200;
        final List<Future<ScanResult>> futures = new ArrayList<>();
        for (int port = 1; port <= 65535; port++) {
            futures.add(portIsOpen(es, ip, port, timeout));
        }
        es.awaitTermination(200L, TimeUnit.MILLISECONDS);
        int openPorts = 0;
        for (final Future<ScanResult> f : futures) {
            if (f.get().isOpen()) {
                openPorts++;
                System.out.println(f.get().getPort());
            }
        }
        System.out.println("There are " + openPorts + " open ports on host " + ip + " (probed with a timeout of "
                + timeout + "ms)");
    }

    public static Future<ScanResult> portIsOpen(final ExecutorService es, final String ip, final int port,
            final int timeout) {
        return es.submit(new Callable<ScanResult>() {
            @Override
            public ScanResult call() {
                try {
                    Socket socket = new Socket();
                    socket.connect(new InetSocketAddress(ip, port), timeout);
                    socket.close();
                    return new ScanResult(port, true);
                } catch (Exception ex) {
                    return new ScanResult(port, false);
                }
            }
        });
    }

    public static class ScanResult {
        private int port;

        private boolean isOpen;

        public ScanResult(int port, boolean isOpen) {
            super();
            this.port = port;
            this.isOpen = isOpen;
        }

        public int getPort() {
            return port;
        }

        public void setPort(int port) {
            this.port = port;
        }

        public boolean isOpen() {
            return isOpen;
        }

        public void setOpen(boolean isOpen) {
            this.isOpen = isOpen;
        }

    }
}