Android Question Http communication in B4x Pages

Private Sub InviaDatiAlDisplay(Testo As String)
    If ipDisplay = "" Then Return
    
    Dim url As String = "http://" & ipDisplay & ":" & portaDisplay & "/update"
    Dim Su As StringUtils
    
    If Testo = "" Then
        Testo = "§" & Main.M.GP_RemoteDisplayDefaultMessage
    End If
    
    Dim datiPost As String = "testo=" & Su.EncodeUrl(Testo, "UTF8")
    
    Try
        ' Impacchettiamo i parametri di questo specifico invio
        Dim parametri() As Object = Array(url, datiPost, ipDisplay, portaDisplay)
        
        ' Li inseriamo nella coda globale (Thread-Safe per la lettura immediata)
        CodaInviiDisplay.Add(parametri)
        
        Dim joContext As JavaObject
        joContext.InitializeContext
        
        ' Creiamo il runnable a vuoto (i parametri li leggeremo dalla coda)
        Dim runnable As Object = joContext.CreateEventFromUI("java.lang.Runnable", "DisplayThread", Null)
        
        Dim joThread As JavaObject
        joThread = joThread.InitializeNewInstance("java.lang.Thread", Array(runnable))
        joThread.RunMethod("start", Null)
        
    Catch
        Log("Errore avvio Thread Display: " & LastException.Message)
    End Try
End Sub

Private Sub DisplayThread_Event (MethodName As String, Args() As Object) As Object
    Try
        ' Preleviamo i primi parametri disponibili nella coda
        If CodaInviiDisplay.Size = 0 Then Return Null
        
        Dim parametri() As Object = CodaInviiDisplay.Get(0)
        CodaInviiDisplay.RemoveAt(0) ' Rimuoviamo subito per i prossimi thread
        
        Dim LocaleUrl As String   = parametri(0)
        Dim LocaleDati As String  = parametri(1)
        Dim LocaleIp As String    = parametri(2)
        Dim LocalePorta As String = parametri(3)
        
        ' --- APERTURA CONNESSIONE NATIVA HTTP IN BACKGROUND ---
        Dim jUrl As JavaObject
        jUrl = jUrl.InitializeNewInstance("java.net.URL", Array(LocaleUrl))
        
        Dim conn As JavaObject = jUrl.RunMethod("openConnection", Null)
        
        conn.RunMethod("setConnectTimeout", Array(1000))
        conn.RunMethod("setReadTimeout", Array(1000))
        conn.RunMethod("setUseCaches", Array(False))
        conn.RunMethod("setDoOutput", Array(True))
        conn.RunMethod("setDoInput", Array(True))
        conn.RunMethod("setRequestMethod", Array("POST"))
        
        Dim hostSpecifico As String = LocaleIp & ":" & LocalePorta
        conn.RunMethod("setRequestProperty", Array("Host", hostSpecifico))
        conn.RunMethod("setRequestProperty", Array("Content-Type", "application/x-www-form-urlencoded"))
        conn.RunMethod("setRequestProperty", Array("Connection", "keep-alive"))
        
        Dim bytes() As Byte = LocaleDati.GetBytes("UTF8")
        conn.RunMethod("setFixedLengthStreamingMode", Array(bytes.Length))
        
        Dim outStream As JavaObject = conn.RunMethod("getOutputStream", Null)
        outStream.RunMethod("write", Array(bytes))
        outStream.RunMethod("flush", Null)
        outStream.RunMethod("close", Null)
        
        Dim responseCode As Int = conn.RunMethod("getResponseCode", Null)
        Log("Risposta Display in BG: " & responseCode)
        
        ' Svuotamento buffer per Keep-Alive
        Dim inStream As JavaObject
        If responseCode >= 200 And responseCode < 300 Then
            inStream = conn.RunMethod("getInputStream", Null)
        Else
            inStream = conn.RunMethod("getErrorStream", Null)
        End If
        
        If inStream.IsInitialized And inStream <> Null Then
            Dim buffer(512) As Byte
            Dim read As Int = 1
            Do While read > 0
                read = inStream.RunMethod("read", Array(buffer))
            Loop
            inStream.RunMethod("close", Null)
        End If
        
    Catch
        Log("Errore durante l'invio in Background: " & LastException.Message)
    End Try
    
    Return Null
End Sub