Need VB code commented to convert it to Java

Question

I am a Java developer. I have the task of converting a VB class to Java.

Can some VB developer comment the following VB code so that I can write its Java equivalent?

Public Class RmaValidationCode
    ' Values for test type
    Public Const SOFTWARE_TEST_TYPE = 0
    Public Const FIRMWARE_TEST_TYPE = 1
    ' Values for test length
    Public Const SHORT_TEST_LENGTH = 0
    Public Const LONG_TEST_LENGTH = 1
    ' Values for test result
    Public Const PASS_TEST_RESULT = 0
    Public Const FAIL_TEST_RESULT = 1
    Public Const ABORT_TEST_RESULT = 2
    Public Const CAUTION_TEST_RESULT = 3
    ' GetRMAValidationCode function bit mapped return values
    Public Const RMA_VC_RET_PASS = 0
    Public Const RMA_VC_RET_NULL_PTR_PARAMETER = 1
    Public Const RMA_VC_RET_INVALID_STR_LENGTH = 2
    Public Const RMA_VC_RET_INVALID_SN_STRING = 4
    Public Const RMA_VC_RET_INVALID_TEST_TYPE = 8
    Public Const RMA_VC_RET_INVALID_TEST_LENGTH = 16
    Public Const RMA_VC_RET_INVALID_TEST_RESULT = 32

    Private Const RMA_LENGTH = 8

    Private rmaValidationCode As String

    ' This function will return the warranty validation code based on serial number, test type, 
    ' test result, test software and test length.
    ' Test type - Generic=0, DST=1
    ' Test result - Pass=0, FAIL=1
    ' Test Software - DOS=0, Windows=1
    ' Test Length - Short=0 Long=1
    Public Function GetRMAValidationCode(ByVal serialNumber As String, ByVal testType As Byte, _
        ByVal testResult As Byte, ByVal testSoftware As Byte, ByVal testLength As Byte)

        Dim returnValue As UInt32
        Dim tempRMACode As String
        Dim tempRMAEnumerator As CharEnumerator
        Dim temp8Bit As Byte

        returnValue = RMA_VC_RET_PASS
        temp8Bit = 0

        ' Make sure we were passed valid strings
        If String.IsNullOrEmpty(serialNumber) OrElse _
           String.IsNullOrEmpty(rmaValidationCode) Then
            returnValue = returnValue Or RMA_VC_RET_NULL_PTR_PARAMETER
        End If

        ' Make sure our strings are big enough
        If serialNumber.Length < RMA_LENGTH OrElse _
           rmaValidationCode.Length < RMA_LENGTH Then
            returnValue = returnValue Or RMA_VC_RET_INVALID_STR_LENGTH
        End If

        ' Assure that valid test types were passed in
        If testType <> SOFTWARE_TEST_TYPE AndAlso _
           testType <> FIRMWARE_TEST_TYPE Then
            returnValue = returnValue Or RMA_VC_RET_INVALID_TEST_TYPE
        End If

        ' Assure that valid test lengths were passed in
        If testLength <> SHORT_TEST_LENGTH AndAlso _
           testLength <> LONG_TEST_LENGTH Then
            returnValue = returnValue Or RMA_VC_RET_INVALID_TEST_LENGTH
        End If

        ' Assure that valid test results were passed in
        If testResult <> PASS_TEST_RESULT AndAlso _
           testResult <> FAIL_TEST_RESULT AndAlso _
           testResult <> ABORT_TEST_RESULT AndAlso _
           testResult <> CAUTION_TEST_RESULT Then
            returnValue = returnValue Or RMA_VC_RET_INVALID_TEST_RESULT
        End If

        If returnValue = RMA_VC_RET_PASS Then
            ' Trim leading and trailing whitespace
            serialNumber.Trim()
            ' Check to see if the serialNumber string is long enough
            ' after whitespace is removed
            If serialNumber.Length < RMA_LENGTH Then
                Return RMA_VC_RET_INVALID_SN_STRING
            End If

            tempRMACode = serialNumber.ToLower()
            tempRMAEnumerator = tempRMACode.GetEnumerator()

            While (tempRMAEnumerator.MoveNext())
                If Not Char.IsLetterOrDigit(tempRMAEnumerator.Current) Then
                    Return RMA_VC_RET_INVALID_SN_STRING
                End If
            End While

            ' Initialize the rmaValidationCode
            rmaValidationCode = ""

            ' Compute and save the first 6 bytes of RMA Validation Code
            temp8Bit = 0
            temp8Bit = Convert.ToByte(tempRMACode.ToCharArray().GetValue(0)) + Convert.ToByte((tempRMACode.ToCharArray()).GetValue(7))
            rmaValidationCode += String.Format("{0:X2}", temp8Bit)

            temp8Bit = 0
            temp8Bit = Convert.ToByte((tempRMACode.ToCharArray()).GetValue(1)) + Convert.ToByte((tempRMACode.ToCharArray()).GetValue(6))
            rmaValidationCode += String.Format("{0:X2}", temp8Bit)

            temp8Bit = 0
            temp8Bit = Convert.ToByte((tempRMACode.ToCharArray()).GetValue(2)) + Convert.ToByte((tempRMACode.ToCharArray()).GetValue(5))
            rmaValidationCode += String.Format("{0:X2}", temp8Bit)

            ' Byte 6 is the Test & Result byte.
            temp8Bit = 0
            temp8Bit = (testSoftware << 3) Or (testResult << 2) Or (testType << 1) Or testLength
            rmaValidationCode += String.Format("{0:X1}", temp8Bit)

            ' Compute the parity byte
            temp8Bit = 0
            Dim mychar As Char
            mychar = rmaValidationCode.ToCharArray().GetValue(3)

            If ((Convert.ToInt32(rmaValidationCode.ToCharArray().GetValue(3), 16) Mod 2) = 1) Then
                temp8Bit = temp8Bit Or (1 << 3)
            Else
                temp8Bit = temp8Bit Or (0 << 3)
            End If

            Dim value As Integer
            mychar = rmaValidationCode.ToCharArray().GetValue(2)
            value = System.Convert.ToInt32(mychar, 16)
            If ((Convert.ToInt32(rmaValidationCode.ToCharArray().GetValue(2), 16) Mod 2) = 1) Then
                temp8Bit = temp8Bit Or (1 << 2)
            Else
                temp8Bit = temp8Bit Or (0 << 2)
            End If

            mychar = rmaValidationCode.ToCharArray().GetValue(1)

            If ((Convert.ToInt32(rmaValidationCode.ToCharArray().GetValue(1), 16) Mod 2) = 1) Then
                temp8Bit = temp8Bit Or (1 << 1)
            Else
                temp8Bit = temp8Bit Or (0 << 1)
            End If

            mychar = rmaValidationCode.ToCharArray().GetValue(0)

            If ((Convert.ToInt32(rmaValidationCode.ToCharArray().GetValue(0), 16) Mod 2) = 1) Then
                temp8Bit = temp8Bit Or 1
            Else
                temp8Bit = temp8Bit Or 0
            End If
            rmaValidationCode += String.Format("{0:X1}", temp8Bit)
        End If

        Return rmaValidationCode
    End Function

    Public Sub New()
        '    serialNumber = "                    "
        rmaValidationCode = "        "
        '  testType = 0
        'testLength = 0
        'testResult = 0
    End Sub
End Class

Answer 1

Actually that is pretty readable and straightforward code. You may want to take a look at VB keywords as well as the AndAlso/OrElse operators (those two sometimes confuse C-style language developers). The rest that's used are just plain old .NET class library methods. Nothing too fancy and you'll find plenty of documentation about those on MSDN.

Answer 2

Unfortunately you're not going to find anyone here that will comment the above code for free.

Visual Basic syntax is relatively simple - it was designed as an entry level language. If you engage your mind and read over the general key words such as AndAlso OrElse WhileNot etc, you shouldn't have a massive issue commenting it yourself.

If you were further interested in the way the code works - the way I usually learn to understand X piece of code is to go step - by - step through it until I finally get the gist of it.

Try searching MSDN for any keywords you don't fully understand.