package concurrentTest;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
/**
* UDP/IP阻塞模式
* */
public class UDPBIO {
/**
* 服务器端和客户端类似
* @param ipStr IP地址
* @param portNum 端口号
* */
public void udpListen(String ipStr, int portNum)
{
try {
//若希望是全双工模式，则启动一个监听端口，承担服务器的职责
//若不能绑定到指定端口，则抛出SocketException
DatagramSocket serverSocket = new DatagramSocket(portNum);
InetAddress server = InetAddress.getByName(ipStr);
byte[] buffer = new byte[65507];
DatagramPacket receivePacket = new DatagramPacket(buffer,buffer.length);
DatagramSocket socket = new DatagramSocket();
DatagramPacket packet = new DatagramPacket(buffer,buffer.length,server,portNum);
//阻塞发送packet到指定的服务器和端口
//网络IO异常，抛出IOExceprion
//连不上IP和端口，抛出PortUnreachableException
socket.send(packet);
//阻塞并同步读取流信息，如接收到的信息流比packet长，则删除更长的信息
serverSocket.receive(receivePacket);
} catch (SocketException e) {
// 若不能绑定到指定端口
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void main(String[] args) {
// TODO Auto-generated method stub
}
}
============================================================================================================================================================================================================================================================================================================================================================================================================
package concurrentTest;
import java.io.IOException;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.MulticastSocket;
import java.net.SocketAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.nio.ByteBuffer;
import java.nio.channels.DatagramChannel;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
/**
* UDP/IP非阻塞模式
* */
public class UDPNIO {
/**
* 服务器端和客户端类似
* @param ipStr IP地址
* @param portNum 端口号
* */
public void udpListen(String ipStr, int portNum)
{
try {
ByteBuffer buffer = ByteBuffer.allocate(1024);
DatagramChannel reveiveChannel = DatagramChannel.open();
reveiveChannel.configureBlocking(false);
DatagramSocket socket = reveiveChannel.socket();
socket.bind(new InetSocketAddress(portNum));
Selector selector = Selector.open();
reveiveChannel.register(selector, SelectionKey.OP_READ);
//之后可采取和TCP/IP NIO中对selector遍历方式进行流信息的读取
DatagramChannel sendChannel = DatagramChannel.open();
sendChannel.configureBlocking(false);
SocketAddress target = new InetSocketAddress(InetAddress.getLocalHost(), portNum);
sendChannel.connect(target);
//阻塞写入流，若发送缓冲区已满，返回0，此时可继续注册OP_WRITE事件
sendChannel.write(buffer);
} catch (SocketException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
/**
* 组播
* */
public void multicaseListen(String ipStr, int portNum)
{
try {
InetAddress groupAddress = InetAddress.getByName(ipStr);
MulticastSocket server = new MulticastSocket(portNum);
//加入组播，若地址为非组播地址，抛出IOException
//若不希望再发送数据到组播地址或者不希望再读取数据，可调用server.leaveGroup(组播地址)
server.joinGroup(groupAddress);
MulticastSocket client = new MulticastSocket();
client.joinGroup(groupAddress);
//
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// 若地址为非组播地址
e.printStackTrace();
}
}
public static void main(String[] args) {
// TODO Auto-generated method stub
}
}
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