Socket与线程——建立socket服务器

思路很简单就是在 web 服务器开启一个死循环的 socket 线程监听客户端的数据，实现一对多的监听。思路很简单但实现起来并不容易，线程阻塞，线程间通信，主函数向线程传值，实现有控制的向 client 客户端发送消息等等很多问题都不好解决，为了解决这些问题也是费尽心思。

SocketThread

public class SocketThread extends Thread {

    private ServerSocket serverSocket = null;

    public SocketThread(ServerSocket serverScoket) {
        try {
            if (null == serverSocket) {
                this.serverSocket = new ServerSocket(8877);
                System.out.println("socket start");
            }
        } catch (Exception e) {
            System.out.println("SocketThread创建socket服务出错");
            e.printStackTrace();
        }

    }

    @Override
    public void run() {
        while (!this.isInterrupted()) {
            int count = 0;
            while (true) {
                try {
                    Socket socket = serverSocket.accept();
                    
                    if (null != socket && !socket.isClosed()) {
                        count++;
                        System.out.println("当前连接"+count);
                        // 处理接受的数据
                        SocketOperate SocketThread = new SocketOperate(socket);
                        SocketThread.start();
                        SocketThread.setPriority(4);//设置优先级避免卡死
                    }
                    socket.setSoTimeout(3000);

                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
    }

    public void closeSocketServer() {
        try {
            if (null != serverSocket && !serverSocket.isClosed()) {
                serverSocket.close();
            }
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

SocketServiceLoader

public class SocketServiceLoader implements ServletContextListener {
    // socket server 线程
    private SocketThread socketThread;

    @Override
    public void contextDestroyed(ServletContextEvent arg0) {
        if (null != socketThread && !socketThread.isInterrupted()) {
            socketThread.closeSocketServer();
            socketThread.interrupt();
        }
    }

    @Override
    public void contextInitialized(ServletContextEvent arg0) {
        // TODO Auto-generated method stub
        if (null == socketThread) {
            // 新建线程类
            socketThread = new SocketThread(null);
            // 启动线程
            socketThread.start();
        }
    }

}

SocketOperate

public class SocketOperate extends Thread {
    

    
    @Autowired
    private ParkSpaceService SpaceService;
    
    public static String res;
    
    private Socket socket;
    
    public void setFlag(boolean flag){
        System.out.println("set is start");

        SocketOperate.flag = flag;
    }
    
    public void setMessage(String msg){
        SocketOperate.ServiceMessage = msg;
    }
    
    
    
    public String getData(){
        return res;
    }

    public SocketOperate(Socket socket) {
        this.socket = socket;
    }
    
    

    @SuppressWarnings("unused")
    public void run() {

        InputStream is = null;
        InputStreamReader isr = null;
        BufferedReader br = null;
        OutputStream os = null;
        PrintWriter pw = null;

        try {

            is = socket.getInputStream();
            isr = new InputStreamReader(is);
            br = new BufferedReader(isr);
            byte[] temp = new byte[1024];  
            int  length = 0; 
            String data = "";
            while((length = is.read(temp)) != -1) {
                data += new String(temp,0,length);              
            }
            System.out.println("客户端对服务端说   " + data);
            res = data;
            /**
             * 客户端返回车场信息，对数据库进行操作
             */
            if(res!=null&&!res.equals("")){

                service//对数据库操作

            }
            socket.shutdownInput();// 关闭socket输入流
            

                // 获取输出流，向客户端输出
                os = socket.getOutputStream();
                pw = new PrintWriter(os);
                pw.write(SocketOperate.ServiceMessage);//向客户端发送内容
                pw.flush();
        
    
            
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // 关闭资源
            if (pw != null)
                pw.close();
            try {
                if (os != null)
                    os.close();
                if (is != null)
                    is.close();
                if (isr != null)
                    isr.close();
                if (br != null)
                    br.close();
                socket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    

        
    }
    

}

这三个类就是基于 socket 服务器的核心代码，合理运用并配合 SSM 框架就可以实现简单的物联操作了