Android与Linux PC通过TCP+ADB反向转发IPC连接成功但收空数据

问题概述 #

尝试通过TCP+ADB反向转发实现Android手机与Linux PC的进程间通信，Android端作为客户端发送字符串laneInfoStr，PC端Python进程作为服务端接收。当前服务端可正常接受连接，但始终收到空字符串。

实现细节 #

ADB端口反向转发命令 #

adb reverse tcp:8888 tcp:8888

Android客户端核心发送代码 #

每次发送会启动新线程执行sendMessage方法：

// 线程启动代码
new Thread(new Runnable() {
    @Override
    public void run() {
        sendMessage();
    }
}).start();

// 消息发送方法
public void sendMessage() {
    Log.d("wlx", String.format("sending: %s", laneInfoStr));
    try (
         Socket socket = new Socket("localhost", 8888)) {
        boolean connected = socket.isConnected(); 
        if (connected) {
            Log.d("wlx", "connected successfully");
        } else {
            Log.e("wlx", "failed to connect");
        }

        OutputStream out = socket.getOutputStream();
        PrintWriter output = new PrintWriter(out);
        output.println(laneInfoStr);
        output.flush();
        output.close();
        Log.d("wlx", "message sent successfully!");
    } catch (IOException e) {
        Log.e("wlx", "failed to send message!");
        Log.e("wlx", e.getMessage());
    }
}

Python服务端代码 #

import socket
import threading

def handle_client(client_socket):
    try:
        request = client_socket.recv(1024)
        print(f"received client's message: {request}")
        client_socket.send("hi from server".encode())
    except IOError:
        print("failed to read client socket or send message")
        client_socket.close()
    finally:
        client_socket.close()

if __name__ == "__main__":
    bind_ip = "0.0.0.0" 
    bind_port = 8888  

    server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    server.bind((bind_ip, bind_port))
    print("[*] Listening on %s:%d" % (bind_ip, bind_port))
    server.listen(5)
    
    while True:
        client, addr = server.accept()
        print("accepted connection from %s:%d" % (addr[0], addr[1]))
        client_handler = threading.Thread(target=handle_client, args=(client,))
        client_handler.start()

已执行操作与日志 #

操作顺序：先启动Python服务端，再启动Android客户端发送消息。

Android客户端日志 #

sending: 00,40
connected successfully
message sent successfully!

Python服务端日志 #

[*] Listening on 0.0.0.0:8888
accepted connection from 127.0.0.1:43823
received client's message: b''

客户端日志显示laneInfoStr非空，且无发送异常，但服务端始终接收空数据。

预期结果 #

服务端应接收到消息，日志输出：

received client's message: b'00,40\n'

实际结果 #

服务端接收空字符串，日志输出：

received client's message: b''

内容的提问来源于stack exchange，提问作者David Yang