java - Java 中的 BufferedReader 和 BufferedWriter null

Question

客户端.java

try {
    try {
        br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
    } catch (IOException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
    try {
        received = br.readLine();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    System.out.println("In-Cmd = " + received);

} finally {
    try {
        br.close();
    } catch (Exception e) {}
}

服务器.java

BufferedWriter bw = null;
try {
    bw = new BufferedWriter(new OutputStreamWriter(connectionSocket.getOutputStream()));
    System.out.println("Out-Cmd = STOP");
    bw.write("stop");
    bw.newLine();
} finally {
    try {
        bw.close();
    } catch (Exception exp) {}
}

所以，我有这个 GUI，客户端可以将文件从本地硬盘上传到服务器，然后我们将复制文件并将它们存储在服务器中。

我可以将 BufferWriter 从客户端发送到服务器完全没有问题，但是当我想从服务器发送到客户端时，我总是收到null

难道我做错了什么？