java BIO编程

BIO简介

BIO是阻塞的I/O,所有的文件操作都是阻塞的。程序在调用读写操作的时候，在数据返回前会一直等待，直到数据包被复制到应用进程的缓冲区或者发生异常的时候才返回。

下面以Socket编程演示java BIO

Socket

服务端开启监听，处理客户端发来的请求。

public static void main(String[] args) {
    //创建ServerSocket并绑定端口
    ServerSocket serverSocket = null;
    try {
        serverSocket = new ServerSocket(10100);
        //监听连接，方法会阻塞直到建立连接

        while (true) {
            Socket socket = serverSocket.accept();

            BIOServerHandle handle = new BIOServerHandle(socket);
            Thread thread = new Thread(handle);
            thread.start();

        }
    } catch (IOException e) {

    } finally {
        if (serverSocket != null) {
            try {
                serverSocket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }


}

BIOServerHandler处理请求

public class BIOServerHandle implements Runnable {

    private Socket socket;

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

    @Override
    public void run() {
        InputStream inputStream = null;
        OutputStream outputStream = null;
        try {
            //读取客户端的数据
            inputStream = socket.getInputStream();
            byte[] buffer = new byte[inputStream.available()];

            inputStream.read(buffer);

            String msg = new String(buffer, "UTF-8");

            System.out.println("服务器接收到客户端的消息：" + msg);


        } catch (Exception e) {

        } finally {
            if (inputStream != null) {
                try {
                    inputStream.close();
                } catch (IOException ex) {
                    ex.printStackTrace();
                }
            }
            if (outputStream != null) {
                try {
                    outputStream.close();
                } catch (IOException ex) {
                    ex.printStackTrace();
                }
            }
            if (socket != null) {
                try {
                    socket.close();
                } catch (IOException ex) {
                    ex.printStackTrace();
                }
            }
        }
    }
}

客户端发起请求

public static void main(String[] args) {
    Socket socket = null;
    OutputStream outputStream = null;
    InputStream inputStream = null;
    try {
        //建立连接
        socket = new Socket("127.0.0.1", 10100);
        outputStream = socket.getOutputStream();

        String msg = "hello--------------";
        System.out.println("向服务器发送消息："+msg);

        //向服务器发送数据
        outputStream.write(msg.getBytes());

    } catch (IOException e) {
        //
    } finally {
        if (inputStream != null) {
            try {
                inputStream.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
        if (outputStream != null) {
            try {
                outputStream.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
        if (socket != null) {
            try {
                socket.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
    }


}

演示结果