Android Question Best practice for storing nested structures

[jamesnz]

I'm sure this is much more simple than I'm making it sound and it's 12 months since I've done much programming
Basically I am pulling xml data from a web api which is made of various nested structures.
I want to be able to group the data together and then iterate through it to do various things.
The specifics are as follows

The xml return contains a set of Motorways, each motorway has some stats in it's parent node
an id
a name
a reference
an average speed
nested inside this motorway is a series of sections which when linked together form the motorway.
Each section has stats like
section name
volume
occupancy
average speed

Each section also has a start and end location
startlocation
start id
start lat
start lng
endlocation
end id
end lat
end lng

I can get the api to send back all motorways( which takes about 20 seconds) or I can get it to send back individual motorways ( ideally I want the user to select some favourite motorways and just pull these every 5 minutes or so)

From here I want to display the average speeds of EACH motorway and then when the user clicks on that motorway I can show the speeds of each section of the motorway by way of a colour coded polyline on a google map.
Currently I've made classes for the motorway , the nested sections, and the further nested startand end locations and I'm using an xml parser . The xml parser populates the motorway and section objects and stores them in a map.

This works well for single motorways but if I download more than one it combines them all into the same map.
I'm confused on whether I should be storing these objects in lists or maps or should I have a list of maps or some other structure?
Is there a best practice method for storing nested data, I'm sure there must be.

the guts of my code is like so

Sub ReadXml(Job As HttpJob)
    Label1.text="made it to readxml"
    Dim In As InputStream
    In = Job.GetInputStream
    parser.Parse(In,"Parser")
   
    In.Close
End Sub

Sub Parser_EndElement (Uri As String, Name As String, Text As StringBuilder)
If parser.parents.Size >0 Then
    If parser.Parents.get(parser.Parents.Size-1) ="return" Then
       
        If Name = "id" Then
        m.id = Text.tostring
        End If
       
        If Name = "name" Then
        m.Name= Text.ToString
        End If
               
        If Name ="averageSpeed" Then 
        m.averageSpeed = Text.ToString
        End If
       
        If Name = "reference" Then
        m.reference = Text.ToString
    Log("motorway class : "&m)
        End If
   
    End If
End If

    If parser.parents.Size >0 Then
    If parser.Parents.get(parser.Parents.Size-1) ="segments" Then
       
        If Name = "averageOccupancy" Then
        Dim tempao As Int = Text.tostring
        s.averageOccupancy = Round2(tempao,1)
        End If
       
        If Name = "averageSpeed" Then
        Dim temp As Int = Text.tostring
        s.averageSpeed= temp
        End If
       
        If Name = "carriagewaySegmentId" Then
        s.carriagewaySegmentId = Text.ToString
        End If
       
        If Name ="id" Then 
        s.id = Text.ToString
        End If
       
        If Name = "lastReadingTime" Then
        s.lastReadingTime = Text.ToString
        End If
       
        If Name = "linkId" Then
        s.linkId = Text.ToString
        End If
       
        If Name = "linkSequence" Then
        s.linkSequence = Text.ToString
        End If
       
        If Name = "reliability" Then
        s.reliability = Text.ToString
        End If
           
        If Name = "sectionEnd" Then
        s.sectionEnd = Text.ToString
        End If
       
        If Name = "sectionLength" Then
        s.sectionLength = Text.ToString
        End If
       
        If Name = "sectionName" Then
        s.sectionName = Text.ToString
        End If
       
        If Name = "sectionOrder" Then
        s.sectionOrder = Text.ToString
        End If
           
        If Name = "sectionStart" Then
        s.sectionStart = Text.ToString
        End If
               
        If Name = "sectionTime" Then
        s.sectionTime = Text.ToString
        End If
       
        If Name = "lastReadingTime" Then
        s.lastReadingTime = Text.ToString
        End If
       
        If Name = "totalVolume" Then
        Dim tempvol As Int = Text.ToString
                s.totalVolume =Round2(tempvol,1)*2
                Log("segment class "&s) ' LOG
                Log("******END OF SECTION******************************")
                ' add objects to map
               
                Main.mapofclasses.Put(("s"&count),s)
                Main.mapofclasses.Put(("sl"&count),sl)
                Main.mapofclasses.Put(("el"&count),el)
        '        Log(s)
        '        Log(sl)
        '        Log(el)
               
                count = count+1
        '        Log("count =" & count)
            'create new objects
            Dim bs As segment
            Dim bsl As startlocation
            Dim bel As endlocation
            ' assign clear objects 
            s = bs
            sl = bsl
            el = bel
        End If 
   
    End If

End If
   
   
    If parser.parents.Size >0 Then
    If parser.Parents.get(parser.Parents.Size-1) ="startLocation" Then
       
        If Name = "description" Then
        sl.description = Text.tostring
        End If
       
        If Name = "id" Then
        sl.id= Text.ToString
        End If
       
        If Name = "latitude" Then
        sl.latitude = Text.ToString
        End If
       
        If Name ="longitude" Then 
        sl.longitude = Text.ToString
        End If
           
        If Name ="speedLimit" Then 
        sl.speedLimit = Text.ToString
        'Log("start location " & sl)
        End If
    End If
    End If

    If parser.parents.Size >0 Then
    If parser.Parents.get(parser.Parents.Size-1) ="endLocation" Then
       
        If Name = "description" Then
        el.description = Text.tostring
        End If
       
        If Name = "id" Then
        el.id= Text.ToString
        End If
       
        If Name = "latitude" Then
        el.latitude = Text.ToString
        End If
       
        If Name ="longitude" Then 
        el.longitude = Text.ToString
        End If
           
        If Name ="speedLimit" Then 
        el.speedLimit = Text.ToString
        'Log("end location" & el)
        End If
    End If
    End If
End Sub

 

[Erel]

Check this: [B4X] Xml2Map - Simple way to parse XML documents