How to escape \n in flat file

[jef_1]

Hi,

We process csv flat files, the line separator is \n, but certain data fields in the file can contain \n too, how can managethis situation properly with ItemReader interface ?

Thanks a lot.
Regards

[michael.lange]

if you know the count of fields per line you could use something like the AggregateItemRerader (from official Spring Batch Samples)

you do not need the header/footer concept, but rather something like a fieldCounter which decides when to set the resultHolder exhausted


[edith says]

I like the concept and created a running proof of concept example in my github repository, it's under "readers", look for "field-count-job.xml".

Only custom code used is:

/**
 * FieldCountItemReader, constructs line by reading from wrapped reader, until
 * field count is reached.
 */
public class FieldCountItemReader implements ItemReader<List<String>> {

    private ItemReader<FieldSet> delegate;
    private int count;

    /** {@inheritDoc} */
    @Override
    public List<String> read() throws Exception {
        List<String> fields = new ArrayList<String>();
        FieldSet field = null;
        // read until end of file
        while ((field = delegate.read()) != null) {
            String[] fieldSetValues = field.getValues();
            for (int i = 0; i < fieldSetValues.length; i++) {
                fields.add(field.getValues()[i]);
            }
            // field count reached ?
            if (fields.size() != count) {
                continue;
            } else {
                return fields;
            }
        }
        // reader returned nothing
        return null;
    }

    public void setCount(int count) {
        this.count = count;
    }

    public void setDelegate(ItemReader<FieldSet> delegate) {
        this.delegate = delegate;
    }
}