package test;

import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;

import sun.applet.Main;

public class ServerSocketTest {
    public static List<Socket> clientSocket = new ArrayList<Socket>();
    
    public ServerSocketTest() throws IOException{
        ServerSocket ss = new ServerSocket(30000);
        System.out.println("服务器启动等待客户端连接");
        while(true){
            Socket s =ss.accept();//等待客户端连接
            clientSocket.add(s);
            System.out.println("客户端总人数"+clientSocket.size());
            //为新用户启动线程
            new UserSocket(s).start();
        }
    }
    public static void main(String[] args) throws IOException {
        new ServerSocketTest();
    }
    
    
    
}

package test;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
import java.net.SocketException;
import java.security.MessageDigest;
import java.util.Iterator;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import sun.misc.BASE64Encoder;

public class UserSocket extends Thread{
    private Socket socket;
    
    public UserSocket(Socket socke){
        this.socket = socke;
    }
    @Override
    public void run() {
        try {
            InputStream is = socket.getInputStream();//获取用户输入流
            OutputStream ops = socket.getOutputStream();//获取用户输出流
            byte[] buff = new byte[1024];//字节
            String red = ""; //用了存放客户端请求过来的内容（客户端信息）
            // 读取数据，此时建立与wabSocket的握手
            int count = is.read(buff);//读取客户端请求内容的长度
            if(count > 0){
                //客户端请求数据转化字符串
                red = new String(buff,0,count);
                //获取WebSocket的值
                String seckey = getSecWebSocketKey(red);
                String response = "HTTP/1.1 101 Switching Protocols\r\nUpgrade: "
                    + "websocket\r\nConnection: Upgrade\r\nSec-WebSocket-Accept: "
                    + getSecWebSocketAccept(seckey) + "\r\n\r\n";
                //推送向客户端
                ops.write(response.getBytes("utf-8"));
            int hasRedad = 0;
            // 不断读取WebSocket发送过来的数据
            System.out.println("while循环前，等待前端推送数据。。。。。。。。。。。。");
            while((hasRedad = is.read(buff))>0){//判断循环读取
                System.out.println("后台接收到值，进入While循环处理");
                /*
                 * 因为WebSocket发送过来的数据遁寻了一定的协议格式， 其中第3~6个字节是数据掩码，
                 * 从第七个字节开始才是真正的有效数据。 因此程序使用第3~6个字节对后面的数据进行了处理
                 */
                for (int i = 0; i < hasRedad - 6; i++) {
                    buff[i + 6] = (byte) (buff[i % 4 + 2] ^ buff[i + 6]);
                }
                //获得从浏览器发送过来的数据
                String pushMsg = new String(buff,6,hasRedad - 6, "utf-8");//第一个值要读取的字节，从第几个开始读取，字符串的总长度，字符集
                //便利Socket集合，向每个Socket对象发送信息
                for (Iterator<Socket> it = ServerSocketTest.clientSocket.iterator();it.hasNext(); ) {
                    try {
                        Socket s = it.next();
                        byte[] pushHead = new byte[2];
                        pushHead[0] = buff[0];
                        pushHead[1] = (byte) pushMsg.getBytes("utf-8").length;
                        //发送前两个字节
                        s.getOutputStream().write(pushHead);
                        //发送有效数据
                        s.getOutputStream().write(pushMsg.getBytes("utf-8"));
                        
                    } catch (SocketException e) {
                        //如果捕获到异常将其从集合中删除
                        // 如果捕捉到异常，表明该Socket已经关闭
                        it.remove();
                    }
                }
                
            }
                
                
                
                
                
            }
            
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }finally{
            try {
                socket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        
        
    }
    
    // 获取WebSocket请求的Seckey
    private String getSecWebSocketKey(String req) {
        // 构建正则表达式，获取Sec-WebSocket-Key:后面的内容
        Pattern p = Pattern.compile("^(Sec-WebSocket-Key:).+",
                Pattern.CASE_INSENSITIVE | Pattern.MULTILINE);
        Matcher m = p.matcher(req);
        if (m.find()) {
            // 提取Sec-WebSocket-Key
            String foundstring = m.group();
            return foundstring.split(":")[1].trim();
        } else {
            return null;
        }
    }

    // 根据WebSocket请求的Seckey计算SecAccept
    private String getSecWebSocketAccept(String key) throws Exception {
        String guid = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
        key += guid;
        MessageDigest md = MessageDigest.getInstance("SHA-1");
        md.update(key.getBytes("ISO-8859-1"), 0, key.length());
        byte[] shalHash = md.digest();
        BASE64Encoder encoder = new BASE64Encoder();
        return encoder.encode(shalHash);
    }
    
    
}