先运行服务端，如果不先连接服务端，就不监听，那客户端不知道连接谁
服务端
import java.io.*;
import java.net.*;
import java.util.ArrayList;
public class QLFWD{
public static ServerSocket server_socket;
public static ArrayList<Socket> socketList=new ArrayList<Socket>();
public static void main(String []args){
try{
server_socket = new ServerSocket(5000);
while(true){
Socket socket = server_socket.accept();
socketList.add(socket); //把sock对象加入sock集合
ServerBO_Thread st=new ServerBO_Thread(socket,socketList); //初始化多线程
st.start();//启动多线程
}
}catch(Exception ex){
ex.printStackTrace();
}finally{
try{
if(server_socket!=null){
server_socket.close();
}
}catch(Exception ex){
ex.printStackTrace();
}
}
}
public void encryptWrite(String src,DataOutputStream output)throws IOException{
//将一个字符串转化为字符数组
//System.out.println(src);
char[] char_arr = src.toCharArray();
//加密操作
for(int i = 0;i<char_arr.length;i++){
output.writeChar(char_arr[i]+13);
}
//用作结束标志符
output.writeChar(2333);
output.flush();
}
//读取并解密
public String readDecrypt(DataInputStream input)throws IOException{
String rtn="";
while(true){
int char_src =input.readChar();
if(char_src!=2333){
rtn=rtn+(char)(char_src-13);
}else{
break;
}
}
return rtn;
}
}
class ServerBO_Thread extends Thread{
Socket client = null;
ArrayList<Socket> clients;
ServerBO_Thread(Socket s,ArrayList<Socket> ss){//初始化
client=s;
clients=ss;
}
public void run(){
DataInputStream input = null;
DataOutputStream output =null;
try{
input = new DataInputStream(client.getInputStream());
QLFWD bo = new QLFWD();
String receive=null;
String send=null;
while(true){//监视当前客户端有没有发来消息
if(!client.isClosed()){
receive=bo.readDecrypt(input);
clients.trimToSize();
String[] param = receive.split("&");
if(")start".equals(param[1])){ //分析客户端发来的内容
send = param[0]+"进入聊天室";
}else{
send = param[0]+"说: "+param[1];
}
if(!("3333".equals(param[1]))){//3333为退出聊天室信号
for(Socket socket:clients){ //遍历socke集合
//把读取到的消息发送给各个客户端
if(!socket.isClosed()){
output = new DataOutputStream(socket.getOutputStream());
bo.encryptWrite(send,output);
}
}
}else{//如果有客户端退出
for(Socket socket:clients){ //遍历socke集合
if(socket!=client){//告诉其他人此人退出聊天室
if(!(socket.isClosed())){
output = new DataOutputStream(socket.getOutputStream());
bo.encryptWrite(param[0]+"已退出聊天室",output);
}
}
}
output = new DataOutputStream(client.getOutputStream());
bo.encryptWrite("3333",output);//返回信号给要退出的客户端，然后关闭线程
client.close();
input.close();
output.close();
}
}else{
break;
}
}
}catch(Exception ex){
ex.printStackTrace();
}
}
}客户端
import java.io.IOException;
import java.util.Scanner;
import java.net.*;
import java.io.*;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.BufferedWriter;
import java.io.BufferedReader;
import java.io.DataOutputStream;
public class QLKHD{
//服务端ip
public String ip = "127.0.0.1";
//服务端端口
public int port = 5000;
public DataOutputStream output = null;
public Socket socket = null;
public DataInputStream input = null;
public Scanner sc =new Scanner (System.in);
public String send ;
public String receive;
public String name;
public String sd = null;
public static void main(String[]aa){
QLKHD po = new QLKHD();
po.start();
}
public void start(){
try{
System.out.println("*******欢迎使用匿名聊天室！**********");
System.out.println("请输入你将要使用的昵称：");
name=sc.nextLine();//获取昵称
socket = new Socket(ip,port);
output=new DataOutputStream(socket.getOutputStream());
input = new DataInputStream(socket.getInputStream());
send = name+"&)start";//把昵称发送到server 告诉所有人有新成员加入聊天室
System.out.println("(如果要退出聊天室请输入“3333”！)");
System.out.println("*******成功进入匿名聊天室！**********");
System.out.println("");
encryptWrite(send,output);
Out out=new Out(output,name,input,socket);
out.start();//启动发送聊天内容的多线程
while(true){
String receive = readDecrypt(input);
if("3333".equals(receive)){//如果收到“3333”则退出聊天室
System.out.println("*******成功退出匿名聊天室！**********");
input.close();
output.close();
socket.close();
System.exit(0);
}
System.out.println(receive);
}
}catch(Exception ex){
ex.printStackTrace();
}finally{
try{
if(socket!=null) socket.close();
input.close();
output.close();
}catch(Exception ex){
ex.printStackTrace();
}
}
}
public void encryptWrite(String src,DataOutputStream output)throws IOException{
//将一个字符串转化为字符数组
char[] char_arr = src.toCharArray();
//加密操作
for(int i = 0;i<char_arr.length;i++){
output.writeChar(char_arr[i]+13);
}
//用作结束标志符
output.writeChar(2333);
output.flush();
}
//读取并解密
public String readDecrypt(DataInputStream input)throws IOException{
String rtn="";
while(true){
int char_src =input.readChar();
if(char_src!=2333){
rtn=rtn+(char)(char_src-13);
}else{
break;
}
}
return rtn;
}
}
class Out extends Thread {
public DataOutputStream output;
public DataInputStream input;
public static String name;
public Socket socket;
public Scanner sc =new Scanner (System.in);
Out(DataOutputStream ot,String n,DataInputStream it,Socket socket){
output=ot;
input=it;
name=n;
}
public void run(){
QLKHD po = new QLKHD();
try{
while(true){
String send=sc.nextLine();//获取用户输入
String send2=name+"&"+send;//把聊天内容打包成约定形式
po.encryptWrite(send2,output);
}
}catch(Exception ex){
ex.printStackTrace();
}finally{
System.out.println("sfef");
}
}
}多次运行客户端增加用户
结果：
