www.pudn.com > exercise.rar > UDPSend2.java
import java.net.*;
import java.io.*;
class UDPSend2
{
public static void main(String[] args)
{
int argc=args.length;
if (args.length!=1)
{
System. out. println("hostname: ");
return;
}
String hostname=args[0];
try{
DatagramSocket socket = new DatagramSocket(2001);
//socket 绑定到一个本地的可用端口,等待接收客户端的请求。
System. out. println("Bound to local port: "+socket.getLocalPort());
InputStream Input=new FileInputStream("f1.txt");
ByteArrayOutputStream bout= new ByteArrayOutputStream();
int data = Input.read();
while(data != -1)
{
bout.write(data);
data= Input.read();
}
Input.close();
byte[] barry=bout.toByteArray();
DatagramPacket packet = new DatagramPacket(barry, barry.length);
System. out. println("looking up hostname "+hostname);
InetAddress remote_addr=InetAddress.getByName(hostname);
packet.setAddress(remote_addr);
packet.setPort(2000);
socket.send(packet);
System. out. println("Packet is sent.");
socket.close();
}catch(java.net.UnknownHostException uhe) {
System. out. println("UnknownHostException");}
catch(java.net.SocketException se) {
System. out. println("SocketException"+se);}
catch(IOException ioe) {
System. out. println("IOException");}
}
}