CSVSourceConverter Class (Extends SourceConverter)
Overview
The CSVSourceConverter, then, is the main driver for the actual conversion. Here are its attributes and methods. It inherits all the attributes and methods of its base classes, the SourceConverter and Converter classes (see Chapter 6).
Attributes:
CSVRecordReader Object
Array of Strings Partner Array
String Schema Location URL
Integer Partner Break Column
String Saved Partner ID
Integer Document Break Column
String Saved Document ID
Methods:
Constructor
processFile
testDocumentBreak
testPartnerBreak
Methods
Constructor
The constructor method for our CSVSourceConverter object sets up that object, but most importantly it also sets up the CSVRecordReader object. Here's the logic for it.
Logic for the CSVSourceConverter Constructor Method
Arguments:
Boolean Validation Option
String Output Directory Name
String File Description Document Name
Call base class constructor
Initialize Partner Array
Call loadFileDescriptionDocument using passed File
Description Document Name
Schema Location URL <- Call File Description Document's
getElementsByTagName on "SchemaLocationURL", then
getAttribute on "value"
IF Schema Location URL is null and Validation is true
Throw Exception
ENDIF
Document Break Column <- Get Document Break Column value from File
Description Document
Partner Break Column <- Get Partner Break Column value from File
Description Document
Initialize Saved Partner ID and Saved Document ID
Create CSVRecordReader object, passing:
File Description Document
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processFile
After the initialization performed in the constructor method, the main processing is performed by the CSVSourceConverter's processFile method. This method converts one input CSV file into one or more output XML documents based on the input parameters.
Logic for the CSVSourceConverter processFile Method
Arguments:
String Name of input file
Returns:
Status or throws exception
Output Directory Path <- Base Directory + directory separator
Initialize Output Document to null
Initialize Sequence Number
Row Grammar <- Get RowDescription from Grammar Element via
getElementsByTagName, and item[0] from NodeList
Open input file
Call CSVRecordReader's setInputStream method
Record Length _<- Call CSVRecordReader's
readRecordVariableLength method
DO while Record Length => 0
Call CSVRecordReader's parseRecord method to parse columns into
DataCell Array, passing Row Grammar Element
Call CSVRecordReader's toXMLType method to convert column contents
in DataCell Array to their schema language datatype
representation
Partner Break <- Call testPartnerBreak
IF Partner Break = true
Output Directory Path <- Base Directory +
Partner ID + directory separator
Lookup Partner in Partner Array
IF Partner is not in Array
Create output directory from Output Directory Path
Partner Array <- Add Partner ID
ENDIF
ENDIF
Document Break <- Call testDocumentBreak
IF Document Break = true or Output Document is null
IF Output Document exists
Call saveDocument
ENDIF
Create new Output Document
Create Root Element, using Root Element Name from Grammar,
and append to Output Document
IF Schema Location URL is not NULL
Create noNamespaceSchemaLocation Attribute and append
to Root Element
ENDIF
Increment Sequence Number, and pad with leading zeroes
to three digits
IF Document Break Column != 0
Output File Path <- Output Directory Path + Root Element
Name + Sequence Number + ".xml"
ELSE
Output File Path <- Output Directory Path + Root Element
Name + ".xml"
ENDIF
Call CSVRecordReader's setOutputDocument method for new
Output Document
ENDIF
Call CSVRecordReader's writeRecord method to write row and column
Elements from CSVRecordReader's DataCall Array, passing
Root Element of Output Document and Row Grammar Element
Record Length <- Call CSVRecordReader's readRecord method
ENDDO
IF Output Document is not null
Call base class saveDocument method
ENDIF
Close input file
Display completion message with number of documents processed
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You'll note that we check for a new partner or document after converting to XML formats via the toXML method. We could check before converting to XML, but performing the conversion first ensures that we are working with data that is not only in string format but also normalized by removing leading and trailing whitespace. The testDocumentBreak and testPartnerBreak methods do the checks for us. Note that if no break is specified for new documents, we unconditionally return false for break on new partner.
testDocumentBreak
This method tests the value of the document break column to determine whether the current row starts a new document.
Logic for the CSVSourceConverter testDocumentBreak Method
Arguments:
None
Returns:
Boolean - true if new partner and false if not
IF Document Break Column is zero
return false
ENDIF
DocumentID <- Call CSVRecordReader's getFieldValue method
passing the Document Break Column number
IF DocumentID = Saved Document ID
return false
ENDIF
Saved Document ID <- Document ID
Return true
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testPartnerBreak
This method tests the value of the partner break column to determine whether the trading partner in the current row is different from that of the preceding document.
Logic for the CSVSourceConverter testPartnerBreak Method
Arguments:
None
Returns:
Boolean - true if new partner and false if not
IF Partner Break Column is zero or if Document Beak Column
is zero
return false
ENDIF
Partner ID <- Call CSVRecordReader's getFieldValue method
passing the Partner Break Column number
IF Partner ID = Saved Partner ID
return false
ENDIF
Saved Partner ID <- Partner ID
Return true
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