个人对socket的理解还不是很深刻，正在学习。
先上传下自己写好的服务端和客户端连接、相应、断开连接的方式。
服务器端
package socket;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
public class SocketService {
static ServerSocket server=null;
static Socket socket =null;
static BufferedReader br; //控制台输入
static BufferedReader in; //读取服务端信息输入流
static PrintWriter writer; //发送给服务端信息的输出流
class Accepter extends Thread{
@Override
public void run() {
String message="";
int i=1;
try {
do{
message = in.readLine();
System.out.println("服务端接收信息第"+i+"次接收到信息为:"+message);
i++;
}while (!"exit".equals(message));
//当客户端输入exit退出后，关闭socket输入流
//in.close(); //这种关闭流的方法会导致socket关闭
socket.shutdownInput();
System.out.println("服务端已停止接收数据");
} catch (IOException e) {
e.printStackTrace();
}
}
}
class Sender extends Thread{
@Override
public void run() {
int i= 1;
String readLine = "";
try {
do{
readLine = br.readLine();
if(null != readLine){
writer.println(readLine);
writer.flush();
}
System.out.println("服务端第"+i+"次发送信息为:"+readLine);
i++;
}while (!"exit".equals(readLine));
br.close();
//writer.close(); //采用流关闭方式会导致socket关闭
socket.shutdownOutput();
System.out.println("服务端停止发送数据");
} catch (IOException e) {
e.printStackTrace();
}
}
}
//搭建服务器端
public static void main(String[] args) throws IOException{
SocketService socketService = new SocketService();
//1、a)创建一个服务器端Socket，即SocketService
socketService.oneServer(socketService);
}
public void oneServer(SocketService socketService){
try{
try{
server=new ServerSocket(5209);
//b)指定绑定的端口，并监听此端口。
System.out.println("服务器启动成功");
//创建一个ServerSocket在端口5209监听客户请求
}catch(Exception e) {
System.out.println("没有启动监听："+e);
//出错，打印出错信息
}
try{
socket=server.accept();
//2、调用accept()方法开始监听，等待客户端的连接
//使用accept()阻塞等待客户请求，有客户
//请求到来则产生一个Socket对象，并继续执行
}catch(Exception e) {
System.out.println("Error."+e);
//出错，打印出错信息
}
Sender sender = socketService.new Sender();
Accepter accepter = socketService.new Accepter();
br = new BufferedReader(new InputStreamReader(System.in));
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
writer = new PrintWriter(socket.getOutputStream());
sender.start();
accepter.start();
}catch(Exception e) {//出错，打印出错信息
System.out.println("Error."+e);
}
}
}
客户端
import java.io.*;
import java.net.Socket;
public class SocketClient {
static Socket socket;
static BufferedReader br; //控制台输入
static BufferedReader in; //读取服务端信息输入流
static PrintWriter writer; //发送给服务端信息的输出流
class Accepter extends Thread{
@Override
public void run() {
int i= 1;
String readLine="";
try {
do{
readLine = in.readLine();
if(null != readLine){
System.out.println(readLine);
}
System.out.println("客户端第"+i+"次接收信息为:"+readLine);
i++;
}while(!"exit".equals(readLine));
//关闭socket输入流
//in.close(); 采用关闭流的方式会导致socket被关闭
socket.shutdownInput();
System.out.println("客户端停止接收数据");
} catch (IOException e) {
e.printStackTrace();
}
}
}
class Sender extends Thread{
@Override
public void run() {
int i= 1;
String readLine ="";
try {
do{
readLine = br.readLine();
if(null != readLine){
writer.println(readLine);
writer.flush();
System.out.println("客户端第"+i+"次发送信息为:"+readLine);
i++;
}
}while (!"exit".equals(readLine));
//当客户端输入exit后关闭socket输出流
br.close();
//writer.close(); 采用流的关闭方式会导致socket关闭
socket.shutdownOutput();
System.out.println("客户端停止发送数据");
} catch (IOException e) {
e.printStackTrace();
}
}
}
// 搭建客户端
public static void main(String[] args) throws IOException {
try {
// 1、创建客户端Socket，指定服务器地址和端口
socket = new Socket("127.0.0.1",5209);
System.out.println("客户端启动成功");
SocketClient socketClient = new SocketClient();
Sender sender = socketClient.new Sender();
Accepter accepter = socketClient.new Accepter();
br = new BufferedReader(new InputStreamReader(System.in));
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
writer = new PrintWriter(socket.getOutputStream());
sender.start();
accepter.start();
} catch (Exception e) {
System.out.println("can not listen to:" + e);// 出错，打印出错信息
}
}
}
说明：运行时必须先启动服务端，否则会报连接异常。
总结：1.关闭socket流会导致socket也被关闭,如果只是想关闭输入或者输出流应该使用socket.shutdownInput()或则socket.shutdownOutput()方法去关闭对于的输入输出流。
2.当socket输入输出流都被关闭后，socket就会自动被关闭。
缺点：只能满足单一的客户端和服务端交互，原因在于服务器端只产生了一个socket,用于接收一个客户端的连接。
