Java基础(14):网络编程之socket

        socket有两种协议通信方式：分别为tcp和udp。

Tcp协议通信

        tcp协议是一种可靠协议，即使网络暂时阻塞，tcp也能保持通信的可靠性。

        服务端：

public class SocketServerTest {

public void init(){

try {

ServerSocket server=new ServerSocket(1000);

Socket in=server.accept();

InputStream input=in.getInputStream();

OutputStream output=in.getOutputStream();

PrintWriter out=new PrintWriter(output,true);

out.println("hello , client!");

System.out.println(input);

System.out.println("server start");

out.close();

output.close();

in.close();

server.close();

} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}

      客服端：

public class SocketClient {

public void init(){
try {

Socket s=new Socket("127.0.0.1",1000);

InputStream in=s.getInputStream();

BufferedReader br=new BufferedReader(new InputStreamReader(in));

String line=br.readLine();

System.out.println(line);

br.close();

s.close();

} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

}

Udp协议通信

      udp协议相对tcp协议是一种不可靠协议，每次传送的数据大小也有限制。

      服务端：

public class UdpServer {

private int SIZE=4096;
private int PORT=1111;
private byte []buf=new byte[SIZE];
private DatagramPacket packet,out;
public void init() throws IOException{
try {
packet=new DatagramPacket(buf, buf.length);
DatagramSocket socket=new DatagramSocket(PORT);
socket.receive(packet);
System.out.println(new String(buf,0,packet.getLength()));
byte[] data=("server receive").getBytes();
out=new DatagramPacket(data,data.length,packet.getSocketAddress());
socket.send(out);

} catch (SocketException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

}

      客户端
public class UdpClient {

private int SIZE=4096;
private String IP="127.0.0.1";
private int PORT=1111;
private byte []buf=new byte[SIZE];
private DatagramPacket packet,out;
public void init() throws IOException{
try {
DatagramSocket socket=new DatagramSocket();
byte[] outBuf=("client say hello").getBytes();
packet=new DatagramPacket(buf, buf.length,InetAddress.getByName(IP),PORT);
out=new DatagramPacket(outBuf, outBuf.length,InetAddress.getByName(IP),PORT);
socket.send(out);
socket.receive(packet);
System.out.println(new String(buf,0,packet.getLength()));
} catch (SocketException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}
}