B4J Question How to return a value？And strange questions

'Handler class
Sub Class_Globals
    Private allSucceeded As Boolean
End Sub

Public Sub Initialize
   
End Sub

Sub Handle(req As ServletRequest, resp As ServletResponse)
    doRequests ' Let another sub handle all the wait for's
    StartMessageLoop ' Only one startmessageloop necessary
    If Not(allSucceeded) Then
        resp.SendError(500, "error....")
    End If
End Sub

Sub doRequests 
    'Process your wait for's here. As structured, they will occur sequentially
    Try
        Wait For (request1) complete (result1 As String)
        'Do the work according to the results of request 1
        If result1="XXXXXX" Then
           wait for (request2) complete (result2 As String)
               If result2 <> "" Then
                allSucceeded = True
            End If
        Else
            Dim data As String = "some data to send"
            wait for (request3(data)) complete (result3 As String)
            If result3 = "" Then
                allSucceeded = True
            End If
        End If
    Catch
        Log($"Encountered error processing doRequests: ${LastException}"$)
    End Try
    StopMessageLoop ' as structured, only one call to stopmessageloop required
End Sub

'For request1, the returned string will trigger different outcomes
Sub request1()As ResumableSub
    Dim result As String
    Dim hp As HttpJob
    hp.Initialize("",Me)
    hp.Download("http://www.example.com")
    Wait For(hp)JobDone(hp As HttpJob)
    'I need to return the result here
    If hp.Success Then
        result = hp.GetString
    Else
        Log($"Encountered error in request1(): ${hp.ErrorMessage}"$)
    End If
    hp.Release
    Return result
End Sub

'For request2, a return of a blank string = failure
Sub request2() As ResumableSub
    Dim result As String
    Dim hp As HttpJob
    hp.Initialize("",Me)
    hp.Download("http://www.example.com")
    Wait For(hp)JobDone(hp As HttpJob)
    'I need to return the result here
       If hp.Success Then
        result = hp.GetString
    Else
        Log($"Encountered error in request2(): ${hp.ErrorMessage}"$)
    End If
    hp.Release
    Return result
End Sub

'For request3, a return of a blank string = success
'Note the usage of SetContentType
Sub request3(data As String) As ResumableSub
    Dim result As String
    Dim hp As HttpJob
    hp.Initialize("",Me)
    hp.PostString("http://www.example.com",data)
    'hp.GetRequest.SetHeader("Content-Type","application/json")
    hp.GetRequest.SetContentType("application/json") ' You're supposed to use the method, not SetHeader, for content type
    hp.GetRequest.SetHeader("Content-Length",data.Length)
    Wait For(hp)JobDone(hp As HttpJob)
    'I need to return the result here
    If Not(hp.Success) Then
        result = $"Encountered error in request3(): ${hp.ErrorMessage}"$
        Log(result)
    End If
    hp.Release
    Return result
End Sub