How to skip lines with ItemReader in Spring-Batch?

Question

I have a custom item reader that transforms lines from a textfile to my entity:

public class EntityItemReader extends AbstractItemStreamItemReader

        

Answer 1

I've had a similar problem for the more general case where I'm using a custom reader. That is backed by an iterator over an object type and returns a new item (of different type) for each object read. Problem is some of those objects don't map to anything, so I'd like to return something that marks that.

Eventually I've decided to define an INVALID_ITEM and return that. Another approach could be to advance the iterator in the read() method, until the next valid item, with null returned if .hasNext() becomes false, but that is more cumbersome.

Initially I have also tried to return a custom ecxeption and tell Spring to skip the item upon it, but it seemed to be ignored, so I gave up (if there are too many invalids isn't performant anyway).