Android Question Google Direction API

Sub traceRoute(JSON As String)
    Dim parser As JSONParser
    parser.Initialize(JSON)
    Dim root As Map = parser.NextObject
    If root.Get("status") = "OK" Then
        Dim routes As List = root.Get("routes")
        For Each colroutes As Map In routes
            Dim bounds As Map = colroutes.Get("bounds")
       
            Dim southwest As Map = bounds.Get("southwest")
            Dim swlat As Double = southwest.Get("lat")
            Dim swlng As Double = southwest.Get("lng")
            Dim sw As LatLng
            sw.Initialize(swlat, swlng)
       
            Dim northeast As Map = bounds.Get("northeast")
            Dim nelat As Double = northeast.Get("lat")
            Dim nelng As Double = northeast.Get("lng")
            Dim ne As LatLng
            ne.Initialize(nelat, nelng)
            Dim posBounds As LatLngBounds
            posBounds.Initialize(sw, ne)
            SetZoom(100, posBounds)
                   
            Dim sb As StringBuilder
            sb.Initialize
            Dim listPoly As List
            listPoly.Initialize
            Dim legs As List = colroutes.Get("legs")
            For Each collegs As Map In legs
                Dim steps As List = collegs.Get("steps")
                For Each colsteps As Map In steps
                    Dim polylineMap As Map = colsteps.Get("polyline")
                    sb.Append(polylineMap.Get("points"))
                Next
            Next
       
            listPoly.AddAll(decodePoly(sb.ToString))
       
            polyRoute = gmap.AddPolyline
            polyRoute.Color = Colors.RGB(255, 241, 89)
       
            polyRoute.Points = listPoly
            For i = 0 To listPoly.Size - 1
                Log("ListPoly: " & listPoly.Get(i))
            Next
            listPoly.Clear
        Next
    Else
        Log("Status: " & root.Get("status"))
    End If

End Sub

Sub decodePoly(encoded As String) As List
    Dim poly As List
    poly.Initialize
    Dim index, len As Int : index = 0 : len = encoded.Length
    Dim lat, lng As Int : lat = 0 : lng = 0

    Do While index < len
        Dim b, b1, shift, result As Int : shift = 0 : result = 0 : b = 0x21
   
        Do While (b >= 0x20)
            Dim bytes() As Byte
            Dim s As String
            s = encoded.CharAt(index)
            bytes = s.GetBytes("UTF8")
            b = bytes(0)
            b = b - 63
            b1 = Bit.AND(b, 0x1f)
            b1 = Bit.ShiftLeft(b1, shift)
            result = Bit.OR(result, b1)
            shift = shift + 5
            index = index + 1
        Loop
   
        Dim dlat As Int
        result = Bit.ShiftRight(result, 1)
        If Bit.AND(result, 1) <> 0 Then
            dlat = Bit.Not(result)
        Else
            dlat = result
        End If
        lat = lat + dlat
   
        If(index = encoded.Length) Then
            Exit
        End If
   
        b = 0x21
        shift = 0
        result = 0
        Do While (b >= 0x20)
            Dim bytes() As Byte
            Dim s As String
            s = encoded.CharAt(index)
            bytes = s.GetBytes("UTF8")
            b = bytes(0)
            b = b - 63
            b1 = Bit.AND(b, 0x1f)
            b1 = Bit.ShiftLeft(b1, shift)
            result = Bit.OR(result, b1)
            shift = shift + 5
            index = index + 1
        Loop
   
        Dim dlng As Int
        result = Bit.ShiftRight(result, 1)
        If Bit.AND(result, 1) <> 0 Then
            dlng = Bit.Not(result)
        Else
            dlng = result
        End If
        lng = lng + dlng
   
        Dim p As LatLng
        p.Initialize(lat / 1E5, lng / 1E5)
        poly.Add(p)
       
    Loop
   
    Return poly
End Sub