Util.java

package arcane.util;

import javax.swing.*;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.util.Collections;
import java.util.Enumeration;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

/**
 * <p>Util class.</p>
 *
 * @author Forge
 * @version $Id: Util.java 10739 2011-07-14 06:39:05Z jendave.hudson@gmail.com $
 */
public class Util {
    /** Constant <code>isMac=System.getProperty("os.name").toLowerCase().indexOf("mac") != -1</code> */
    static public final boolean isMac = System.getProperty("os.name").toLowerCase().indexOf("mac") != -1;
    /** Constant <code>isWindows=System.getProperty("os.name").toLowerCase().indexOf("windows") == -1</code> */
    static public final boolean isWindows = System.getProperty("os.name").toLowerCase().indexOf("windows") == -1;

    /** Constant <code>threadPool</code> */
    static public ThreadPoolExecutor threadPool;
    /** Constant <code>threadCount</code> */
    static private int threadCount;

    static {
        threadPool = new ThreadPoolExecutor(4, 4, 0L, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<Runnable>(), new ThreadFactory() {
            public Thread newThread(Runnable runnable) {
                threadCount++;
                Thread thread = new Thread(runnable, "Util" + threadCount);
                thread.setDaemon(true);
                return thread;
            }
        });
        threadPool.prestartAllCoreThreads();
    }

    /**
     * <p>broadcast.</p>
     *
     * @param data an array of byte.
     * @param port a int.
     * @throws java.io.IOException if any.
     */
    public static void broadcast(byte[] data, int port) throws IOException {
        DatagramSocket socket = new DatagramSocket();
        broadcast(socket, data, port, NetworkInterface.getNetworkInterfaces());
        socket.close();
    }

    /**
     * <p>broadcast.</p>
     *
     * @param socket a {@link java.net.DatagramSocket} object.
     * @param data an array of byte.
     * @param port a int.
     * @param ifaces a {@link java.util.Enumeration} object.
     * @throws java.io.IOException if any.
     */
    private static void broadcast(DatagramSocket socket, byte[] data, int port, Enumeration<NetworkInterface> ifaces)
            throws IOException {
        for (NetworkInterface iface : Collections.list(ifaces)) {
            for (InetAddress address : Collections.list(iface.getInetAddresses())) {
                if (!address.isSiteLocalAddress()) continue;
                // Java 1.5 doesn't support getting the subnet mask, so try the two most common.
                byte[] ip = address.getAddress();
                ip[3] = -1; // 255.255.255.0
                socket.send(new DatagramPacket(data, data.length, InetAddress.getByAddress(ip), port));
                ip[2] = -1; // 255.255.0.0
                socket.send(new DatagramPacket(data, data.length, InetAddress.getByAddress(ip), port));
            }
        }
    }

    /**
     * <p>invokeAndWait.</p>
     *
     * @param runnable a {@link java.lang.Runnable} object.
     * @throws java.lang.Exception if any.
     */
    public static void invokeAndWait(Runnable runnable) throws Exception {
        try {
            SwingUtilities.invokeAndWait(runnable);
        } catch (Exception ex) {
            throw new Exception("Error invoking runnable in UI thread.", ex);
        }
    }
}