概述
关于网络的基础知识，请自行google，这里通过socket（tcp）来实现一个简单的对话。
Tcp协议的Socket
服务端四步走：
1.创建服务端socket并绑定端口号
2.开始监听
3.读取客户端信息
4.向客户端发送信息
package tcp;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.ServerSocket;
import java.net.Socket;
public class Server {
public static void main(String[] args) {
ServerSocket serverSocket = null;
try {
// 1.创建服务端socket并绑定端口号
serverSocket = new ServerSocket(8888);// 系统占用的端口号0-1024
// 2.开始监听
System.out.println("******************开始监听****************");
while (true) {// 死循环，持续监听
Socket socket = serverSocket.accept();// 进入阻塞状态，等待客户端连接
HandleThread handleThread = new HandleThread(socket);// 有客户端连接则新启一个线程来处理
handleThread.start();
}
} catch (IOException e) {
e.printStackTrace();
} finally {
//关闭资源
try {
if (serverSocket != null) {
serverSocket.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* 处理客户端连接的线程
*
* @author xiao
*
*/
static class HandleThread extends Thread {
private BufferedReader br;
private InputStreamReader isr;
private InputStream is;
private OutputStream os;
private OutputStreamWriter osw;
private BufferedWriter bw;
private Socket mSocket;
public HandleThread(Socket socket) {
mSocket = socket;
}
@Override
public void run() {
// 3.读取客户端信息
try {
is = mSocket.getInputStream();
isr = new InputStreamReader(is);
br = new BufferedReader(isr);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = br.readLine()) != null) {
sb.append(line);
}
System.out.println("客户端说：" + sb);
// 4.向客户端发送信息
os = mSocket.getOutputStream();
osw = new OutputStreamWriter(os);
bw = new BufferedWriter(osw);
bw.write("hello,我是服务端");
bw.flush();
mSocket.shutdownOutput();
} catch (IOException e) {
e.printStackTrace();
} finally {
// 释放资源
try {
if (bw != null) {
bw.close();
}
if (osw != null) {
osw.close();
}
if (os != null) {
os.close();
}
if (br != null) {
br.close();
}
if (isr != null) {
isr.close();
}
if (is != null) {
is.close();
}
if (mSocket!=null) {
mSocket.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
客户端三步走：
1.创建socket连接
2.向服务端发送消息
3.读取服务端消息
package tcp;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.Socket;
public class Client {
public static void main(String[] args) {
OutputStream os= null;
OutputStreamWriter osw= null;
BufferedWriter bw= null;
InputStream is= null;
InputStreamReader isr = null;
BufferedReader br = null;
Socket socket= null;
try {
// 1.创建socket连接 地址-->localhost:8888
socket = new Socket("localhost", 8888);
System.out.println("******************客户端连接服务端***********************");
// 2.向服务端发送消息
os = socket.getOutputStream();
osw = new OutputStreamWriter(os);
bw = new BufferedWriter(osw);
bw.write("hello,我是客户端"+(int)(Math.random()*100));//用随机数模拟不同客户端请求服务器
bw.flush();
socket.shutdownOutput();
// 3.读取服务端消息
is = socket.getInputStream();
isr = new InputStreamReader(is);
br = new BufferedReader(isr);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = br.readLine()) != null) {
sb.append(line);
}
System.out.println("服务端说：" + sb);
} catch (IOException e) {
e.printStackTrace();
} finally {
//关闭资源
try {
if (br != null) {
br.close();
}
if (isr != null) {
isr.close();
}
if (is != null) {
is.close();
}
if (bw != null) {
bw.close();
}
if (osw != null) {
osw.close();
}
if (os != null) {
os.close();
}
if (socket != null) {
socket.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
测试一下
先启动服务端，再启动客户端（多次启动，模拟多用户访问服务器）
服务端打印：
image.png
客户端打印
image.png
