In my previous post I wrote about whyI use object oriented Lotusscript. Let’s look at how it can be used in a real-life application.
Background
At my work I developed a system to handle insurance claims. Each claim can have one or more claimants, people or parties that have either BI (bodily injury) or PD (property damage) claims related to an accident. Each claimant get a reserve setup, an amount of money the adjuster think it will cost to settle the claimant. There are two reserves for each claimant, one for loss payments and one for expense payments. The latter can be payments for police reports, field adjusters, lawyer fees, etc while loss payments are the actual damages (payments to body shops, medical payments, etc).
When payments are made, the reserve amounts are reduced, until reaching zero. No more payments can be done then until the reserve is increased. Each adjuster have a limit to how large reserve he or she can set, higher reserve must be approved by a manager.
When payments are made, the reserve amounts are reduced, until reaching zero. No more payments can be done then until the reserve is increased. Each adjuster have a limit to how large reserve he or she can set, higher reserve must be approved by a manager.
Data storage
When the claim system was first put in place, all reserves and payments werestored in the Notes database. They were then (manually) transferred into a backend system built in Visual FoxPro. But after a few years, a COM object (dsClaimLink) was developed and the Notes database is now sending all financial transaction into the backend, and retrieving financial information the same way when needed. Claim information is stored in the Notes database, as is claimant information. Some claimant information. a sub-set of the data stored in Notes,is sent to the backend as well.
Original design
Initially I built a large number of functions and subroutines, organized in different script libraries based on functionality.This actually worked really good, and the code was fairly easy to maintain, modify and expand. When the financial transactions were moved to the backend, I just had to modify the function GetAvailableAmount() to call the backend instead of looking up the amount in the Notes database. But it was still not very flexible, andI had some code that was duplicated in many places (most of it related to calling the COM object). So about two years ago, I started refactoring my code, both to make it faster and easier to maintain, by using object oriented Lotuscript.
Example
Beloware examples of the code in the script library Class.ClaimData class. This is not my exact production code, I have removed a number of lines to make the example more clear.
The ClaimData class (described in next posting)contains an array of claimants, each of those an object. Each claimant object in turn contains an object containing the different amounts (loss reserve/loss payments, expense reserve/expense payments, recovery amount, etc).
First, let’s look at the AmountData object.
Class AmountData Public lr As Currency ' Loss Reserve Public er As Currency ' Expense Reserve Public lp As Currency ' Loss Payments Public ep As Currency ' Expense Payments Public slp As Currency ' Supplemental Loss Payments Public sep As Currency ' Supplemental Expense Payments Public rec As Currency ' Recovery amount Public lossavail As Currency Public expavail As Currency Public Sub New() rec = 0 slp = 0 sep = 0 lr = 0 er = 0 lp = 0 ep = 0 lossavail = -1 expavail = -1 End Sub Public Sub Load(claimnumber As String, claimant As Integer) Dim success As Integer Dim servaddress As String Dim xmldata As String Dim claimlink As ClaimLink ' Object to connect to backend Set ClaimLink = New ClaimLink() ' Create object/class If claimant = 0 Then ' Get total amounts for all claimants success = claimlink.GetClaimStatus(claimnumber, Today()) Else ' Get amounts for selected claimant success = claimlink.GetAmountsByClaimant(claimnumber, claimant, Today()) End If If success = True Then ' Data returned successfully xmldata = claimlink.GetDataXML() rec = Cstr(Ccur(XMLGetValue(xmldata,"recovery"))) slp = Cstr(0-Ccur(XMLGetValue(xmldata,"losssup"))) sep = Cstr(0-Ccur(XMLGetValue(xmldata,"expsup"))) If claimant = 0 Then ' All claimants lr = Cstr(Ccur(XMLGetValue(xmldata,"lossorig")) + Ccur(XMLGetValue(xmldata,"losschg"))) er = Cstr(Ccur(XMLGetValue(xmldata,"exporig")) + Ccur(XMLGetValue(xmldata,"expchg"))) Else ' Specified claimant lr = Cstr(Ccur(XMLGetValue(xmldata,"lossres")) - Ccur(slp) + Ccur(rec)) er = Cstr(Ccur(XMLGetValue(xmldata,"expres")) - Ccur(sep)) End If lp = Cstr(0-Ccur(XMLGetValue(xmldata,"losspaid")) - Ccur(slp)) ep = Cstr(0-Ccur(XMLGetValue(xmldata,"exppaid")) - Ccur(sep)) lossavail = Ccur(lr) - Ccur(lp) expavail = Ccur(er) - Ccur(ep) End If End Sub End Class
As you perhaps noticed, I encapsulated the dsClaimLink functionality in an obect as well. I am also using my own XML parsing functions, as the system was built in Notes R5.
When the object is created, I do not lead the amounts directly. I just set all amounts to 0, with two exceptions. The available amounts are set to -1 (a value they will normally never have). This indicate that data have not been loaded, or that the attempt to load data failed.
The Load() method of the class call the COM object (dsClaimLink) withone of two functions depending on how the method is called. This let meuse the AmountData object notjust for amounts for a specified claimant, but also for claim level amounts,totals for all claimants.
Next we have a small object used to decide if a claimant is open or closed.The expense and loss parts of a claimant can be closed and (re-)openedindividually. If either is open, the claimant is open, if both are closed, the claimant is considered closed. That is why I built this object, to get an easy status indication in the claimant object.
Class ClaimantStatusData Public loss As String Public expense As String Public claimant As String Public Sub new(doc As NotesDocument) If Lcase(doc.LossClosed(0)) = "yes" Then Me.loss = "closed" Else Me.loss = "open" End If If Lcase(doc.ExpensesClosed(0)) = "yes" Then Me.expense = "closed" Else Me.expense = "open" End If If Me.expense = "closed" Then If Me.loss = "closed" Then Me.claimant = "closed" Else Me.claimant = "open" End If Else Me.claimant = "open" End If End Sub End Class
Nothing very complicated, but a big help later on.
The final class I will show today is the actual ClaimantData class. As you can see,I am using the classed I described earlier here. I have removed some code in order to make it easier to follow. Just one more note, I use a field/value called ParentUNID to keep track of all documents that belong to a claim. The claim number is not associated with the claim at first, so I needed some other unique identifier. I choose to use the UniversalID of the main document (“Loss Notice”) at the time it is received into the database. Even if the actual UniversalID would change, e.g. through a replication conflict, that field will never change again.
The class is farly simple. The ClaimantData object will load amount and claimant status wheninitialized. They are then available, together with the methods of the class, to the calling code.
Class ClaimantData Public claimantdoc As NotesDocument Public unid As String ' Store UniversalID of claimant document Public parentunid As String Public amounts As AmountData Public claimcare As ClaimCareData Public status As ClaimantStatusData Public Parallel As Integer Public Sub New(doc As NotesDocument) Dim claimnumber As String Dim claimant As Integer Set claimantdoc = doc unid = doc.UniversalID parentunid = doc.GetItemValue("ParentUNID")(0) claimnumber = doc.GetItemValue("ClaimNumber")(0) claimant = Cint(doc.GetItemValue("Claimant_Number")(0)) If Lcase(doc.GetItemValue("TransferredToParallel")(0)) = "yes" Then Parallel = True Else Parallel = False End If Set amounts = New Amounts(claimnumber, claimant) Set status = New ClaimantStatusData(doc) End Sub Public Function GetValue(fieldname) As Variant GetValue = claimantdoc.GetItemValue(fieldname)(0) End Function Public Function SetValue(fieldname, Byval value As Variant) As Variant Call claimantdoc.ReplaceItemValue(fieldname, value) End Function Public Function GetVariant(fieldname) As Variant GetVariant = claimantdoc.GetItemValue(fieldname) End Function Public Sub Save() Call claimantdoc.Save(True,True) End Sub Public Function DisplayName() As String If Fulltrim(GetValue("Claimant_Name")) = "" Then DisplayName = GetValue("Claimant_Company") Else DisplayName = GetValue("Claimant_Name") End If End Function Public Function GetXML() Dim tempxml As String If claimantdoc Is Nothing Then Msgbox "Claimant document is not loaded, no data returned.",,"ClaimantData.GetXML()" GetXML = "" Exit Function End If tempxml = "<claimntno>" & claimantdoc.GetValue("Claimant_Number") & "</claimntno>" & CRLF tempxml = tempxml + "<extclmntno>" & claimantdoc.getValue("ClaimantNumberExternal") & "</extclmntno>" & CRLF tempxml = tempxml + "<classcode>" & claimantdoc.pClassCode(0) & "</classcode>" & CRLF tempxml = tempxml + "<cvgcode>" & claimantdoc.Claimant_LossType(0) & "</cvgcode>" & CRLF tempxml = tempxml + "<table>" & claimantdoc.pTable(0) & "</table>" & CRLF If claimantdoc.Unknown(0)="Yes" Then tempxml = tempxml + "<claimntnam>* unknown *</claimntnam>" & CRLF Elseif claimantdoc.Claimant_Name(0)="" Then tempxml = tempxml + "<claimntnam>" & dsClaimLink.EncodeXML(claimantdoc.Claimant_Company(0)) & "</claimntnam>" & CRLF Else tempxml = tempxml + "<claimntnam>" & dsClaimLink.EncodeXML(claimantdoc.Claimant_Name(0)) & "</claimntnam>" & CRLF End If ' Check if we have amounts loaded If Not amounts Is Nothing Then tempxml = tempxml + "<lossamt>" & Format$(amounts.lp,"###0.00") & "</lossamt>" & CRLF tempxml = tempxml + "<expamt>" & Format$(amounts.ep,"###0.00") & "</expamt>" & CRLF End If GetXML = tempxml End Function End Class
There is a function to get an XML representation of the claimant. This one is used when data is sent to the dsClaimLink COM object. I also have a function to return the name to display, either the person name or the company name of the former is blank. I could have implemented this using the Get/Set statements, but they have to be defined as a pair and this is a read-only property of the object.