B4J Question doubt on ServerSockect and multiple access

[marcick]

I have doubts my code is correct about ServerSocket when multiple connections can occour in the same time.
I think the string SerBuffer is the same for all the connections and I should use a separate buffer for each connection. I'm a bit confused, anybody can help me ?
How can I declare a separate buffer for each connection ?

Sub Class_Globals
    Public Bls1ServerSocket As ServerSocket
    Private SerBuffer, Bls1String As String
    Private Bls1PORT As Int
    Private working As Boolean = True
End Sub

'Initializes the object. You can add parameters to this method if needed.
Public Sub Initialize
    Conf=File.ReadMap(File.DirApp, "config.properties")
    Bls1PORT=Conf.Get("Bls1Port")
    Bls1ServerSocket.Initialize(Bls1PORT, "server")
    ListenForBls1Connections
    Log("Bls1Connector is listening on port: " & Bls1PORT)
End Sub

Private Sub ListenForBls1Connections
    Do While working
        Bls1ServerSocket.Listen
        Wait For Server_NewConnection (Successful As Boolean, NewSocket As Socket)   
        If Successful Then   
            'Log("New connection from " & NewSocket.RemoteAddress)
            Dim astream As AsyncStreams
            astream.Initialize(NewSocket.InputStream,NewSocket.OutputStream,"astream")
            'NewSocket.TimeOut=15000
        End If
    Loop
End Sub

Sub AStream_NewData (Buffer() As Byte)
    Dim astream As AsyncStreams = Sender
    Dim bc As Bls1Client=Main.Bls1ClientMap.Get(astream)
    bc.Time=DateTime.now
    Main.Bls1ClientMap.Put(astream, bc)
    SerBuffer=SerBuffer & BytesToString(Buffer, 0, Buffer.Length, "utf-8")
    If SerBuffer.IndexOf(Chr(13))=-1 Then Return

 

[Erel]

Why not use jServer to create a real server?

Two examples of a low level server supporting multiple clients:
1. MJPEG server: https://www.b4x.com/android/forum/threads/mjpeg-cctv-server.73792/#content
2. FTP server: https://www.b4x.com/android/forum/t...d-with-socket-and-asyncstreams.74320/#content

 

[marcick]

I'll have a look, but at this time I don't want to start from scratch, I would prefer to tune the actual project.
So I'm right that the SerBuffer variable is shared between all the connections ?
Or do I have a separate SerBuffer for each connection that is created ?

 

[marcick]

Ok, I think I have the answer, The Serbuffer is shared between all the connection and this can bring to unexpected behaviours. mad:)
So I have corrected the code using the Map, where each connection has its own buffer
Thank you, I'll have a look to jServer then

Sub AStream_NewData (Buffer() As Byte)
    Dim astream As AsyncStreams = Sender
    Dim bc As Bls1Client=Main.Bls1ClientMap.Get(astream)
    bc.Time=DateTime.now
    bc.SerBuff=bc.SerBuffer & BytesToString(Buffer, 0, Buffer.Length, "utf-8")
    Main.Bls1ClientMap.Put(astream, bc)
    If bc.SerBuffer.IndexOf(Chr(13))=-1 Then Return

 

[KMatle]

Yep. That's the way I'm using it.

 

[Erel]

So I have corrected the code using the Map, where each connection has its own buffer

The simplest way, and I've implemented it in both ways, is to implement the communication code in a class and create a new instance for each client.

 

[marcick]

The code in the first post is a class module, but I have one single instance for all the client, right ?
How should be modified to have a new instance for each client ?

 

[Erel]

but I have one single instance for all the client, right ?

Yes.

How should be modified to have a new instance for each client ?

https://www.b4x.com/android/forum/threads/mjpeg-cctv-server.73792/#content

 

[marcick]

ok, I'll study it, thanks