Need VB code commented to convert it to Java - vb.net

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.