Cannot catch exception in spring batch's ItemWriter

I'm writing a Spring Batch process to migrate a dataset from one system into another. In this case this is as simple as using a RowMapper implementation to build the object from a query before handing off to the ItemWriter. The ItemWriter calls the save method on my DAO (defined as an interface and handled by spring data)

The issue is this: I have a unique constraint on the MyItem table, and therefore saving a duplicated record will result in a DataIntegrityViolationException. I have tried catching this within the ItemWriter to allow me to log that a record was not imported, however during execution it never enters this catch statement. I have attempted catching Exception AND Throwable to no avail too.

From what I've noticed, there is a @Transactional annotation on the 'save' method of my DAO where I would expect the commit and flush to occur. Does Spring Batch alter this transaction in any way? Such that the @Transactional annotation applies to the 'write' method of the ItemWriter?

Can I even catch the exception in this class?

I've provided code snippets below, if you need further information - please let me know.

Many thanks for any help you can provide

ItemWriter

@Component
public class MyItemWriter implements ItemWriter<MyItem> {

    private static final Logger LOG = LoggerFactory.getLogger(MyItemWriter.class);

    @Resource
    private MyItemDao myItemDao;

    @Override
    public void write(List<? extends MyItem> myItems) throws Exception {
        for (MyItem myItem : myItems) {
            try {
                myItemDao.save(myItem);
            } catch (Throwable ex) {
                LOG.warn("Failed to import MyItem: {}: {} ", myItem.getId(), ex.toString());
            }
        }
    }
}

DAO

public interface MyItemDao extends PagingAndSortingRepository<MyItem, Integer> {
    [Custom methods omitted]
}

Spring Batch configuration

<batch:job id="myImportJob" restartable="true" job-repository="jobRepository">
    <batch:step id="myImportStep" allow-start-if-complete="true">
        <batch:tasklet>
            <batch:chunk reader="myItemReader" writer="myItemWriter" commit-interval="50" />
        </batch:tasklet>
    </batch:step>
</batch:job>