Reader

From DISMARC Help

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A reader is part of an Importer

So-called RecordReaders transform the native data into an XML. RecordReaders are configured via the ImporterConfig which will set certain settings before you can get an iterator for a parsed file. What does that mean? Well, lets say that you have a really long text file where you have to break at each line starting with a BEGIN RECORD. You would need quite a lot of memmory to read the whole file especially when we need to convert it into a different character encoding. That's why you need to tell the RecordReader that you need to break at each of the BEGIN RECORD lines, hand it over to the Mapper and continue to read the file as soon as the mapper has finished converting the record. This behaviour is called Iterator because we go through each record at a time. The RecordReaders create theses RecordIterators for each file you've uploaded to the application.

So far, the application can handle the following native data and generate an XML out of it.

CsvRecordReader

The CsvRecordReader iterates through each line of the supplied file and returns an XML with an element for each column. It takes the following settings:

Enclosure 

What character surrounds the value of a field in the CSV

Escape 

What character escapes the following character (which is needed to escape the enclosure for example)

Delimiter 

What character is used to split the line into the fields

FirstLineIsHeader 

Is the first line the header line, then this line will be used as attribute for the XML output

ExcelXMLRecordReader

Since Office2003, Excel is capable of saving XML files. These files are read just like CVS files but this Reader can handle multiple tables.

FirstLineIsHeader 

Is the first line the header line, then this line will be used as attribute for the XML output

Iso2709RecordReader

This Reader doesn't take any settings as it uses the standard. It will create a MARC-XML out of the text file.

XmlRecordReader

This Reader will split the XML at a certain XPath. the following settings are needed:

Path

The XPath for which will return each of the nodes

Namespace

for XPath to work, you may need to specify some namespaces. Use <prefix>=<namepsace> for this value. You can use this setting multiple times.

SequentialRecordReader

SeparatedSequentialRecordReader

MysqlDatabaseRecordReader

This reader is configured using an XML that is used as import file.

MarcTextRecordReader

OaiRecordReader