BluetoothServerSocket
class BluetoothServerSocket : Closeable
| kotlin.Any | |
| ↳ | android.bluetooth.BluetoothServerSocket |
A listening Bluetooth socket.
The interface for Bluetooth Sockets is similar to that of TCP sockets: java.net.Socket and java.net.ServerSocket. On the server side, use a BluetoothServerSocket to create a listening server socket. When a connection is accepted by the BluetoothServerSocket, it will return a new BluetoothSocket to manage the connection. On the client side, use a single BluetoothSocket to both initiate an outgoing connection and to manage the connection.
For Bluetooth BR/EDR, the most common type of socket is RFCOMM, which is the type supported by the Android APIs. RFCOMM is a connection-oriented, streaming transport over Bluetooth BR/EDR. It is also known as the Serial Port Profile (SPP). To create a listening BluetoothServerSocket that's ready for incoming Bluetooth BR/EDR connections, use BluetoothAdapter.listenUsingRfcommWithServiceRecord().
For Bluetooth LE, the socket uses LE Connection-oriented Channel (CoC). LE CoC is a connection-oriented, streaming transport over Bluetooth LE and has a credit-based flow control. Correspondingly, use BluetoothAdapter.listenUsingL2capChannel() to create a listening BluetoothServerSocket that's ready for incoming Bluetooth LE CoC connections. For LE CoC, you can use getPsm() to get the protocol/service multiplexer (PSM) value that the peer needs to use to connect to your socket.
After the listening BluetoothServerSocket is created, call accept() to listen for incoming connection requests. This call will block until a connection is established, at which point, it will return a BluetoothSocket to manage the connection. Once the BluetoothSocket is acquired, it's a good idea to call #close() on the BluetoothServerSocket when it's no longer needed for accepting connections. Closing the BluetoothServerSocket will not close the returned BluetoothSocket.
BluetoothServerSocket is thread safe. In particular, #close will always immediately abort ongoing operations and close the server socket.
Summary
| Public methods | |
|---|---|
| BluetoothSocket! |
accept()Block until a connection is established. |
| BluetoothSocket! |
Block until a connection is established, with timeout. |
| Unit |
close()Immediately close this socket, and release all associated resources. |
| Int |
getPsm()Returns the assigned dynamic protocol/service multiplexer (PSM) value for the listening L2CAP Connection-oriented Channel (CoC) server socket. |
| String |
toString() |
Public methods
accept
fun accept(): BluetoothSocket!
Block until a connection is established.
Returns a connected BluetoothSocket on successful connection.
Once this call returns, it can be called again to accept subsequent incoming connections.
close can be used to abort this call from another thread.
| Return | |
|---|---|
BluetoothSocket! |
a connected BluetoothSocket |
| Exceptions | |
|---|---|
java.io.IOException |
on error, for example this call was aborted, or timeout |
accept
fun accept(timeout: Int): BluetoothSocket!
Block until a connection is established, with timeout.
Returns a connected BluetoothSocket on successful connection.
Once this call returns, it can be called again to accept subsequent incoming connections.
close can be used to abort this call from another thread.
| Return | |
|---|---|
BluetoothSocket! |
a connected BluetoothSocket |
| Exceptions | |
|---|---|
java.io.IOException |
on error, for example this call was aborted, or timeout |
close
fun close(): Unit
Immediately close this socket, and release all associated resources.
Causes blocked calls on this socket in other threads to immediately throw an IOException.
Closing the BluetoothServerSocket will not close any BluetoothSocket received from accept().
| Exceptions | |
|---|---|
java.lang.Exception |
if this resource cannot be closed |
java.io.IOException |
if an I/O error occurs |
getPsm
fun getPsm(): Int
Returns the assigned dynamic protocol/service multiplexer (PSM) value for the listening L2CAP Connection-oriented Channel (CoC) server socket. This server socket must be returned by the BluetoothAdapter#listenUsingL2capChannel() or android.bluetooth.BluetoothAdapter#listenUsingInsecureL2capChannel(). The returned value is undefined if this method is called on non-L2CAP server sockets.
| Return | |
|---|---|
Int |
the assigned PSM or LE_PSM value depending on transport |
toString
fun toString(): String
| Return | |
|---|---|
String |
a string representation of the object. |