--- a/src/wifibroadcast/WifiBroadcast.java	Sun Jul 29 12:10:17 2012 +0900
+++ b/src/wifibroadcast/WifiBroadcast.java	Sun Jul 29 14:37:12 2012 +0900
@@ -61,7 +61,7 @@
 		return InetAddress.getByName("192.168.100.66");
 	}
 
-	public InetAddress getBroadcast() throws SocketException {
+	public static InetAddress getBroadcast() throws SocketException {
 		Enumeration<NetworkInterface> interfaces =
 				NetworkInterface.getNetworkInterfaces();
 		while (interfaces.hasMoreElements()) {

--- a/src/wifibroadcast/WifiBroadcastTest.java	Sun Jul 29 12:10:17 2012 +0900
+++ b/src/wifibroadcast/WifiBroadcastTest.java	Sun Jul 29 14:37:12 2012 +0900
@@ -18,6 +18,7 @@
 	int sender_count = 1;
 	WifiReceiver wbr[] = new WifiReceiver[receiver_count];
 	WifiReceiver wbs[] = new WifiReceiver[sender_count];
+	private boolean bchannel;
 
 	public static void main(String args[]) {
 		new WifiBroadcastTest().test(args);
@@ -33,7 +34,11 @@
 			} else if (mchannel) {
 				for(int i=0;i<wbr.length;i++) wbr[i] = new WifiMulticastChannel(i,MCASTADDR,port,WifiReceiver.SocketType.Receiver);
 				Thread.sleep(timeout/4);
-				for(int i=0;i<wbs.length;i++) wbs[i] = new WifiMulticastChannel(i,MCASTADDR,port,WifiReceiver.SocketType.Sender);
+				for(int i=0;i<wbs.length;i++) wbs[i] = new WifiMulticastChannel(i,MCASTADDR,port,WifiReceiver.SocketType.Sender);			
+			} else if (bchannel) {
+				for(int i=0;i<wbr.length;i++) wbr[i] = new WifiBroadcastChannel(i,port,WifiReceiver.SocketType.Receiver);
+				Thread.sleep(timeout/4);
+				for(int i=0;i<wbs.length;i++) wbs[i] = new WifiBroadcastChannel(i,port,WifiReceiver.SocketType.Sender);
 			} else {
 				for(int i=0;i<wbr.length;i++) wbr[i] = new WifiBroadcast(i,port,WifiReceiver.SocketType.Receiver);
 				Thread.sleep(timeout/4);
@@ -50,14 +55,34 @@
 
 	public void options(String[] args) {
 		for(int i=0;i<args.length;i++) {
-			if (args[i].equals("-m")) multicast = true;
-			else if (args[i].equals("-channel")) mchannel = true;
-			else if (args[i].equals("-r"))  { i++; receiver_count = getOptInt(args, count, i); wbr = new WifiReceiver[receiver_count]; }
-			else if (args[i].equals("-s"))  { i++; sender_count = getOptInt(args, count, i); wbs = new WifiReceiver[sender_count]; }
-			else if (args[i].equals("-c")) { i++; count = getOptInt(args, count, i);}
-			else if (args[i].equals("-t")) { i++; timeout = getOptInt(args, count, i);}
-			else if (args[i].equals("-T")) { i++; testSize = getOptInt(args, count, i);}
-			else if (args[i].equals("-p")) { i++; port = getOptInt(args, count, i);}
+			switch(args[i]) {
+			case "-m": multicast = true; break;
+			case "-channel": mchannel = true; break;
+			case "-bchannel": bchannel = true; break;
+			case "-r":  i++; receiver_count = getOptInt(args, receiver_count, i); wbr = new WifiReceiver[receiver_count];  break;
+			case "-s":  i++; sender_count = getOptInt(args, sender_count, i); wbs = new WifiReceiver[sender_count];  break;
+			case "-c":  i++; count = getOptInt(args, count, i); break;
+			case "-t":  i++; timeout = getOptInt(args, (int) timeout, i); break;
+			case "-T":  i++; testSize = getOptInt(args, testSize, i); break;
+			case "-p":  i++; port = getOptInt(args, port, i); break;
+			case "-a":  i++; MCASTADDR = getOptString(args, MCASTADDR, i); break;
+      default: i++;
+         System.out.println(
+           "(default)  Broadcast DatagramSocket\n"+
+           "-m         Multicast DatagramSocket\n"+
+           "-cahnnel   Multicast with DatagramChannel\n"+
+           "-bcahnnel  Broadcase with DatagramChannel\n"+
+           "-r  N      create N receivers\n"+
+           "-s  N      create N senders\n"+
+           "-c  N      send count packet\n"+
+           "-t  N      timeout N msec\n"+
+           "-T  N      send N byte packet\n"+
+           "-p  N      broadcast/multicast port\n"+
+           "-a  S      broadcast/multicast address\n"+
+           "-h          print this\n"+
+           ""
+         );
+      }
 		}
 	}
 
@@ -96,7 +121,10 @@
 		return count;
 	}
 
-
+	public String getOptString(String[] args, String str, int i) {
+		if (i<args.length) { str = args[i]; }
+		return str;
+	}
 
 	public Thread sender(final WifiReceiver wbs, final int count) {
 		Runnable sender = new Runnable() {

--- a/src/wifibroadcast/WifiMulticast.java	Sun Jul 29 12:10:17 2012 +0900
+++ b/src/wifibroadcast/WifiMulticast.java	Sun Jul 29 14:37:12 2012 +0900
@@ -2,7 +2,6 @@
 
 import java.io.IOException;
 import java.nio.ByteBuffer;
-
 import java.net.DatagramPacket;
 import java.net.InetAddress;
 import java.net.MulticastSocket;

--- a/src/wifibroadcast/WifiMulticastChannel.java	Sun Jul 29 12:10:17 2012 +0900
+++ b/src/wifibroadcast/WifiMulticastChannel.java	Sun Jul 29 14:37:12 2012 +0900
@@ -14,12 +14,14 @@
 import java.nio.channels.spi.SelectorProvider;
 
 public class WifiMulticastChannel implements WifiReceiver {
-	private InetAddress mAddr;
-	private DatagramChannel dc;
-	private SocketAddress sAddr;
+	protected InetAddress mAddr;
+	protected DatagramChannel dc;
+	protected SocketAddress sAddr;
 	// select on DatagramChannel does not work now
-	private Selector selector;
-	private boolean selectMode = false; 
+	protected Selector selector;
+	protected boolean selectMode = false; 
+	
+	public WifiMulticastChannel() {}
 
 	public WifiMulticastChannel(int id, String mCASTADDR, int port, SocketType sender) throws IOException {
 		// join multicast group on this interface, and also use this
@@ -39,7 +41,6 @@
 		dc = DatagramChannel.open(StandardProtocolFamily.INET)
 				.setOption(StandardSocketOptions.SO_REUSEADDR, true)
 				.setOption(StandardSocketOptions.IP_MULTICAST_IF, ni);
-
 		mAddr = InetAddress.getByName(mCASTADDR);
 		sAddr = new InetSocketAddress(mAddr,port);
 		dc.join(mAddr, ni);