Key-value mapping in BeanIO fixed-length record

Question

I have the following specification for a fixed-length data file (refer to record-C type of specification, page 4)

a second part, having a length of 1,800 characters, consisting of a table of 75 elements to be used for the display of the only data present in the communication; each of these elements is constituted by a field-code of 8 characters and by a field-value of 16 characters

It means that the first 89 characters (omitted in the above summary) are plain old fixed-length and then, for the remaining 1800, I have to take them into groups of key-value pairs each counting up to 24 characters. Blank spaces are trimmed and empty pairs are not considered in the process.

Ideally, my bean may be constructed like

public class RecordC{

    private List<Pair<String, String>> table = new ArrayList<>(MAX_TABLE_SIZE); //I don't want to use Map **yet**

}

Something can be e.g. Apache Common's Pair<String,String> or anything suitable for KVP mapping.

I understand that I can create a whole TypeHandler that takes the full 1800 bytes but I wanted to exploit the power of BeanIO.

Here is what I have done so far

    <record name="RECORD_C" class="it.csttech.ftt.data.beans.ftt2017.RecordC" order="3" minOccurs="1" maxOccurs="1" maxLength="2000">
        <field name="tipoRecord" rid="true" at="0" ignore="true" required="true" length="1" lazy="true" literal="C" />

        <field name="cfContribuente" at="1" length="16" align="left" trim="true" lazy="true" />
        <field name="progressivoModulo" at="17" length="8" padding="0" align="right" trim="true" lazy="true" />
        <field name="spazioDisposizioneUtente" at="25" length="3" align="left" trim="true" lazy="true" />
        <field name="spazioUtente" at="53" length="20" align="left" trim="true" lazy="true" />

        <field name="cfProduttoreSoftware" at="73" length="16" align="left" trim="true" lazy="true" />

        <segment name="table" collection="list" lazy="true" class="org.apache.commons.lang3.tuple.ImmutablePair">
            <field name="key" type="java.lang.String" at="0" length="8" trim="true" lazy="true" setter="#1" />
            <field name="value" type="java.lang.String" at="8" length="16" trim="true" lazy="true" setter="#2" />
        </segment>

        <field name="terminatorA" at="1897" length="1" rid="true" literal="A" ignore="true" />
    </record>

Unfortunately this does not work in testing. I get only a single record in the list, decoded at positions [0-7] and [8-23] instead of expected [89-113][114-???][....][....]

Question is: how do I in BeanIO declare repeating fixed-length fields?

Answer 1

I have currently resolved my unmarshalling problem by removing all at attributes in the RecordC specifications. As I found out, the "at" attribute is absolute to the record and not relative to the repeating segment. However this forced me to add some ignored fields in the unmarshalling at the sole cost of a few ignores.

I will test the marshalling against the official controller once I have data