13.5. Multi-Record Field Definition Example

This is a CSV message: 
book,22 Britannia Road,Amanda Hodgkinson
magazine,Time,April,2011
magazine,Irish Garden,Jan,2011
book,The Finkler Question,Howard Jacobson
The CSV reader processes the message as shown: 
<csv:reader fields="book[name,author] | magazine[*]" rootElementName="sales" indent="true" />
This is the resulting output: 
<sales>
    <book number="1">
        <name>22 Britannia Road</name>
        <author>Amanda Hodgkinson</author>
    </book>
    <magazine number="2">
        <field_0>Time</field_0>
        <field_1>April</field_1>
        <field_2>2011</field_2>
    </magazine>
    <magazine number="3">
        <field_0>Irish Garden</field_0>
        <field_1>Jan</field_1>
        <field_2>2011</field_2>
    </magazine>
    <book number="4">
        <name>The Finkler Question</name>
        <author>Howard Jacobson</author>
    </book>
</sales>
Note the syntax in the 'fields' attribute. Each record definition is separated by the pipe character '|'. Each record definition is constructed as record-name[field-name,field-name]. record-name is matched against the first field in the incoming message and so used to select the appropriate record definition to be used for outputting that record. Also note how you can use an asterisk character ('*') when you do not want to name the record fields. In this case (as when extra/unexpected fields are present in a record), the reader will generate the output field elements using a generated element name e.g. "field_0", "field_1" etc.