Cannot connect to socket via bluetooth - JVM exception occurred: read failed, socket might closed or timeout, read ret: -1

[simon2x]

• Python: 3.5.2
• OS: Android 7.1.2

Description

I am trying to connect to bluetooth module HC-06 from android device. The code below will successfully detect paired devices but will not connect - raising "JVM exception occurred: read failed, socket might closed or timeout, read ret: -1".

Code and Logs

12-11 12:57:36.876 26500 26535 I python  :    File "main.py", line 57, in build
12-11 12:57:36.877 26500 26535 I python  :      self.recv_stream, self.send_stream = get_socket_stream('HC-06')
12-11 12:57:36.877 26500 26535 I python  :    File "main.py", line 46, in get_socket_stream
12-11 12:57:36.879 26500 26535 I python  :      socket.connect()
12-11 12:57:36.879 26500 26535 I python  :    File "jnius_export_class.pxi", line 638, in jnius.JavaMethod.__call__ (jnius/jnius.c:22410)
12-11 12:57:36.880 26500 26535 I python  :    File "jnius_export_class.pxi", line 732, in jnius.JavaMethod.call_method (jnius/jnius.c:23494)
12-11 12:57:36.881 26500 26535 I python  :    File "jnius_utils.pxi", line 93, in jnius.check_exception (jnius/jnius.c:3741)
12-11 12:57:36.882 26500 26535 I python  :  jnius.JavaException: JVM exception occurred: read failed, socket might closed or timeout, read ret: -1
12-11 12:57:36.986 26500 26535 I python  : Python for android ended.

Permissions

android.permissions = INTERNET,BLUETOOTH,BLUETOOTH_ADMIN,BLUETOOTH_PRIVILEGED,ACCESS_WIFI_STATE,ACCESS_NETWORK_STATE

Here is example function taking name of bluetooth device as arg.

def get_socket_stream(name):
    paired_devices = BluetoothAdapter.getDefaultAdapter().getBondedDevices().toArray()
    print("PAIRED: ", paired_devices)
    socket = None
    for device in paired_devices:#
        print(device.getName())
        if device.getName() == name:
            print(device.getName())
            
            # socket = device.createInsecureRfcommSocketToServiceRecord(
                # UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"))
            socket = device.createRfcommSocketToServiceRecord(
                UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"))
            recv_stream = socket.getInputStream()
            send_stream = socket.getOutputStream()
            break
            
    socket.connect()
    return recv_stream, send_stream

[cheath2013]

I am having the same issue using similar code. Has any solution been found?

[Ruud14]

I am facing the same error too, has any of you found a solution yet?

[Ruud14]

For me the issue was that I didn't use '00001101-0000-1000-8000-00805F9B34FB'

[KeyWeeUsr]

This is not a PyJNIus bug, it's a normal Java error. However, take a look at this answer and you might find the solution.

[Giammi77]

Can't understan how to fix the problem in kivy please help me thank you
Gianmaria

[soficshift]

Me too. Could somebody help?

[Hmerman6006]

The problem is that when you use UUID to create a createRfcommSocketToServiceRecord socket on Android post 4.2 the socket may not be acceptable i.e. -1. So if you are still struggling to get an answer (which took me 5 hrs to grasp) try one of the following:
1] After creating the socket check if the port is less than one and assign a new port number > 0 -

if socket.port <= 0:
            socket = device.createRfcommSocket(1)
            if not socket.connected:
                socket.connect()

2] Use java class createInsecureRfcommSocketToServiceRecord(UUID) instead (have not tried this one)
[https://stackoverflow.com/questions/18657427/ioexception-read-failed-socket-might-closed-bluetooth-on-android-4-3](Link to insecure rfcomm comments)

Hope this helps, because when I originally clicked on this link, the drips and drabs of linked answers was quite political.

[Enkumicahel]

Hello guys,
Has anyone been able to figure a solution for this one?

[ps2229]

AttributeError: 'android.bluetooth.BluetoothSocket' object has no attribute 'port'
I am getting this error after using the above solution does anyone know how to solve this?

[alexmosc]

AttributeError: 'android.bluetooth.BluetoothSocket' object has no attribute 'port' I am getting this error after using the above solution does anyone know how to solve this?

I also has had this error following the solution by @Hmerman6006

Maybe in three years the API in Python changed?

[Sahil-pixel]

Is there any solution i ma facing same problem !

request_permissions([Permission.BLUETOOTH_CONNECT,\
                Permission.BLUETOOTH_SCAN,Permission.BLUETOOTH,\
                Permission.BLUETOOTH_ADMIN,], callback)
def get_socket_stream(name):
    paired_devices = BluetoothAdapter.getDefaultAdapter().getBondedDevices().toArray()
    socket = None
    for device in paired_devices:
        print("#"*20)
        print(device.getName(),device.getAddress())
        if device.getName() == name:
            print("name matched")
            show_toast("Name match!!!!!!!!!!")
           

            #int_class = IntegerClass.TYPE

            uuid=UUID.fromString("00001101-0000-1000-8000-00805F9B34FB")
            socket = device.createInsecureRfcommSocketToServiceRecord(uuid)
            BluetoothAdapter.getDefaultAdapter().cancelDiscovery()
            #createRfcommSocketToServiceRecord(uuid)
            #c=AndroidString("createRfcommSocket")
            #create_rfcomm_socket_method = device.getClass().getMethod(c, [int_class])
            # Invoke the method with the required argument
            #socket = create_rfcomm_socket_method.invoke(device, 1)

            print(socket)
            
            socket.connect()

i got same error
read failed, socket might closed or timeout, read ret: -1
flutter community facing similar issue
edufolly/flutter_bluetooth_serial#154 (comment)