FixedLength giving issues while trying to fetch only a subset of values

Question

I do have a file which have many records or columns in a single row. This file is being used across multiple systems. Hence not all fields are required for my requirement. Hence if i set only a subset of values as shown below

<property name="lineTokenizer">
    <bean class="org.springframework.batch.item.file.transform.FixedLengthTokenizer">
        <property name="names" value="aa,cc,vv,bb" />
        <property name="columns" value="1-578,579-579,580-580,581-581" />
    </bean>
</property>

I get an exception as below

org.springframework.batch.item.file.transform.IncorrectLineLengthException: Line is shorter than max range 581
org.springframework.batch.item.file.transform.FixedLengthTokenizer.doTokenize(FixedLengthTokenizer.java:109)
org.springframework.batch.item.file.transform.AbstractLineTokenizer.tokenize(AbstractLineTokenizer.java:112)
org.springframework.batch.item.file.mapping.DefaultLineMapper.mapLine(DefaultLineMapper.java:43)
org.springframework.batch.item.file.FlatFileItemReader.doRead(FlatFileItemReader.java:180)

Do we have to do anything special to fetch only subset of values

Answer 1

The exception is saying that the line is shorter than the range you're providing. As in, you're mapping too many columns, not too few.

That being said, you need to map the entire record in the FixedLengthTokenizer. However, the FieldSetMapper you use doesn't need to use all those fields.