[网络协议]TCP网络编程传输文本类文件时保存文件为空白的问题

使用TCP网络编程进行客户端向服务器端传输文件，代码如下：
客户端：
@Test
public void client(){
Socket socket = null;
OutputStream outputStream = null;

    BufferedInputStream bufferedInputStream = null;
    try {
        // 根据地址获取服务端IP对象
        InetAddress byName = InetAddress.getByName("127.0.0.1");
        // 获取socket套接字
        // IP地址 + 端口号
        socket = new Socket(byName,8898);
        // 获取socket的输出流
        outputStream = socket.getOutputStream();

        bufferedInputStream = new BufferedInputStream(new FileInputStream(new File("C:\\Users\\86133\\Desktop\\test.txt")));

        int len;
        byte[] bytes  = new byte[1024];
        while ((len = bufferedInputStream.read(bytes)) != -1) {
            outputStream.write(bytes,0,len);
        }
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        try {
            socket.close();
            outputStream.close();
            bufferedInputStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

服务器端：
@Test
public void server(){
ServerSocket serverSocket = null;
Socket socket = null;
InputStream inputStream = null;
BufferedOutputStream bufferedOutputStream = null;
try {
// 这个端口号是自己创建的server端口号，
// client端正是根据这个端口号发送信息的
serverSocket = new ServerSocket(8898);
socket = serverSocket.accept();
inputStream = socket.getInputStream();

        bufferedOutputStream = new BufferedOutputStream(new FileOutputStream(new File("C:\\Users\\86133\\Desktop\\test2.txt")));
        int len;
        byte[] bytes = new byte[1024];
        while ((len = inputStream.read(bytes)) != -1){
            String s = String.valueOf(bytes);
            bufferedOutputStream.write(bytes,0,len);
        }
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        try {
            serverSocket.close();
            socket.close();
            inputStream.close();
            
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

结果：
test2.txt文件夹中没有任何信息：

对服务器端进行debug，发现一直到文件输出流写入文件部分都没有问题，写入的byte数组是有值的：

只有可能是文件关闭部分出现问题，发现输出缓冲流bufferedOutputStream未关闭！这会导致文件写入失败！！！

修改后的服务器端：
@Test
public void server(){
ServerSocket serverSocket = null;
Socket socket = null;
InputStream inputStream = null;
BufferedOutputStream bufferedOutputStream = null;
try {
// 这个端口号是自己创建的server端口号，
// client端正是根据这个端口号发送信息的
serverSocket = new ServerSocket(8898);
socket = serverSocket.accept();
inputStream = socket.getInputStream();

        bufferedOutputStream = new BufferedOutputStream(new FileOutputStream(new File("C:\\Users\\86133\\Desktop\\test2.txt")));
        int len;
        byte[] bytes = new byte[1024];
        while ((len = inputStream.read(bytes)) != -1){
            String s = String.valueOf(bytes);
            bufferedOutputStream.write(bytes,0,len);
        }
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        try {
            serverSocket.close();
            socket.close();
            inputStream.close();
            bufferedOutputStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}

结果：test2.txt文件成果写入。