java 通信 协议_Java——通信协议

一、基于socket通信——TCP

客户端输入一个hello，服务端进行输出

这个传输过程就是先建立一个会话，然后有一个流，基于TCP的套接字完成

//基于socket通信的服务端

public class ServerSocket_Server {

public static void main(String[] args) throws IOException {

//

ServerSocket serverSocket=null;

//

BufferedReader bufferedReader=null;

try {

//打开一个服务 8080端口

serverSocket=new ServerSocket(8080);

//接收一个客户端连接，等的客户端连接

//socket中基于流作为传输

Socket socket=serverSocket.accept();

//获得输入流

bufferedReader=new BufferedReader(new InputStreamReader(socket.getInputStream()));

System.out.println(bufferedReader.readLine());//输出

}catch (IOException e){

e.printStackTrace();

}finally {

if(bufferedReader!=null){

bufferedReader.close();

}

if(serverSocket!=null){

serverSocket.close();

}

}

}

}

//客户端

public class ServerSocket_Client {

public static void main(String[] args) throws IOException {

Socket socket=null;

try {

//用socket建立连接

socket=new Socket("127.0.0.1",8080);

//传输

PrintWriter out=new PrintWriter(socket.getOutputStream(),true);

out.println("hello");

}catch (Exception e){

e.printStackTrace();

}finally {

if(socket!=null){

socket.close();

}

}

}

}

二、基于DatagramSocket的通信——UDP

public class UDPServerDemo {

public static void main(String[] args) throws IOException {

DatagramSocket datagramSocket=null;

try {

//创建服务，并且接收一个数据包

datagramSocket=new DatagramSocket(8080);

byte[] receiveData=new byte[1024];

//接收数据的数据包

DatagramPacket receivePacket=new DatagramPacket(receiveData,receiveData.length);

datagramSocket.receive(receivePacket);

//收到数据之后输出来

System.out.println(new String(receiveData,0,receivePacket.getLength()));

}finally {

if(datagramSocket!=null){

datagramSocket.close();

}

}

}

}

public class UDPClientDemo {

public static void main(String[] args) throws IOException {

DatagramSocket datagramSocket=new DatagramSocket();

try {

//获得地址信息

InetAddress address=InetAddress.getByName("localhost");

byte[] sendData="Hello,whm".getBytes();

//要发送的数据包

DatagramPacket sendPacket=new DatagramPacket(sendData,sendData.length,address,8080);

//发送

datagramSocket.send(sendPacket);

}catch (IOException e){

e.printStackTrace();

}finally {

if(datagramSocket!=null){

datagramSocket.close();

}

}

}

}

三、双向通信——全双工

public class DoubleSocketServer {

public static void main(String[] args) throws IOException {

ServerSocket serverSocket=null;

try {

serverSocket=new ServerSocket(8080);//监听端口号

//等待客户端连接

Socket socket=serverSocket.accept();

//通过BufferedReader拿到客户端输入流

BufferedReader is=new BufferedReader(new InputStreamReader(socket.getInputStream()));

//输出流

PrintWriter os=new PrintWriter(socket.getOutputStream());

//通过控制台信息作为坐蓐

BufferedReader sin=new BufferedReader(new InputStreamReader(System.in));

//拿到客户端信息

System.out.println("Client:"+is.readLine());

String line=sin.readLine();

while (!line.equals("bye")){

os.println(line);//输出数据

os.flush();//清空缓存

System.out.println("Server:"+line);

System.out.println("Client:"+is.readLine());

line=sin.readLine();

}

os.close();

is.close();

socket.close();

}catch (IOException e){

e.printStackTrace();

}finally {

if(serverSocket!=null){

serverSocket.close();

}

}

}

}

//客户端基于socket建立通信

public class DoubleSocketClient {

public static void main(String[] args) throws IOException {

Socket socket=new Socket("127.0.0.1",8080);

try {

//拿到输入流

BufferedReader sin=new BufferedReader(new InputStreamReader(System.in));

PrintWriter os=new PrintWriter(socket.getOutputStream());

BufferedReader is=new BufferedReader(new InputStreamReader(socket.getInputStream()));

String line=sin.readLine();

while (!line.equals("bye")){

os.println(line);

os.flush();//清空

System.out.println("Client:"+line);

System.out.println("Server:"+is.readLine());

line=sin.readLine();

}

}finally {

socket.close();

}

}

}