网络通信，现在随处可见，任何东西不涉及网络的话，就感觉少了条手臂，断了个腿一样，今天就来聊聊网络通信；
Paste_Image.png
Paste_Image.png
下面来看看socket的原理：
Paste_Image.png
- 基于TCP的Socket编程
Paste_Image.png
下面来看看例子：
Server
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;
//服务器类
public class Server {
public static void main(String[] args) throws Exception {
// 实例化一个list,用于保存所有的User
List list = new ArrayList();
// 创建绑定到特定端口的服务器套接字
@SuppressWarnings("resource")
ServerSocket serverSocket = new ServerSocket(9999);
System.out.println("服务端正在开始~");
// 循环监听客户端连接
while (true) {
Socket socket = serverSocket.accept();
// 每接受一个线程，就随机生成一个一个新用户
User user = new User("user" + Math.round(Math.random() * 100),socket);
System.out.println(user.getName() + "正在登录。。。");
list.add(user);
// 创建一个新的线程，接收信息并转发
ServerThread thread = new ServerThread(user, list);
thread.start();
}
}
}
ServerThread
import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;
/*
* 服务器线程的作用主要是:
* 1.接收来自客户端的信息
* 2.将接收到的信息解析，并转发给目标客户端
* */
public class ServerThread extends Thread {
private User user;
private List list;
public ServerThread(User user, List list) {
this.user = user;
this.list = list;
}
public void run() {
try {
while (true) {
// 信息的格式：(login||logout||say),发送人,收发人,信息体
//不断地读取客户端发过来的信息
String msg= user.getBr().readLine();
System.out.println(msg);
String[] str = msg.split(",");
switch (str[0]) {
case "logout":
remove(user);// 移除用户
break;
case "say":
sendToClient(str[1], msg); // 转发信息给特定的用户
break;
default:
break;
}
}
} catch (Exception e) {
System.out.println("异常");
} finally {
try {
user.getBr().close();
user.getSocket().close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
private void sendToClient(String username, String msg) {
for (User user : list) {
if (user.getName().equals(username)) {
try {
PrintWriter pw =user.getPw();
pw.println(msg);
pw.flush();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
private void remove(User user2) {
list.remove(user2);
}
}
Client
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
/*
* client线程主要是负责：
* 1.发送信息
* 2.一直接收信息，并解析
* */
public class Client {
public static void main(String[] args) {
try {
Socket socket = new Socket("localhost", 9999);
//开启一个线程接收信息，并解析
ClientThread thread=new ClientThread(socket);
thread.setName("Client1");
thread.start();
//主线程用来发送信息
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
PrintWriter out=new PrintWriter(socket.getOutputStream());
while(true)
{
String s=br.readLine();
out.println(s);
//out.write(s+"\n");
out.flush();
}
}catch(Exception e){
System.out.println("服务器异常");
}
}
}
ClientThread
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.Socket;
/**
* 作用：一直接收服务端转发过来的信息
* */
public class ClientThread extends Thread {
private Socket socket;
public ClientThread(Socket socket) {
this.socket = socket;
}
public void run() {
try {
InputStream inputStream = socket.getInputStream();
InputStreamReader inputStreamReader = new InputStreamReader(
inputStream);
BufferedReader br = new BufferedReader(inputStreamReader);
try {
// 信息的格式：(login||logout||say),发送人,收发人,信息体
while (true) {
String msg=br.readLine();
System.out.println(msg);
String[] str = msg.split(",");
switch (str[0]) {
case "say":
System.out.println(str[2] + " 对 " + str[1] + " say: "
+ str[3]);
break;
default:
break;
}
}
} catch (Exception e) {
e.printStackTrace();
}
} catch (IOException e1) {
e1.printStackTrace();
}
}
}
User
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
public class User {
private String name;
private String account;
private Socket socket;
private BufferedReader br;
private PrintWriter pw;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAccount() {
return account;
}
public void setAccount(String account) {
this.account = account;
}
public Socket getSocket() {
return socket;
}
public void setSocket(final Socket socket) {
this.socket = socket;
}
public BufferedReader getBr() {
return br;
}
public void setBr(BufferedReader br) {
this.br = br;
}
public PrintWriter getPw() {
return pw;
}
public void setPw(PrintWriter pw) {
this.pw = pw;
}
public User(String name, final Socket socket) throws IOException {
this.name = name;
this.socket = socket;
this.br = new BufferedReader(new InputStreamReader(
socket.getInputStream()));
this.pw = new PrintWriter(socket.getOutputStream());
}
@Override
public String toString() {
return "User [name=" + name + ", account=" + account + ", socket="
+ socket + "]";
}
}
结果
result.gif