Bean property is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter? Spring Batch

Question

I am developing Spring Batch CompositeItemReader & Writer Example. I developed XML file and able to compile code successfully, but when running mu sample co

Answer 1

Spring is trying to get the property cutomerNumber from the String class :

 Invalid property 'customerNumber' of bean class [java.lang.String]

which is wrong because the String is not supposed to be configured as the item of your job 's step, the Item in this context is supposed to be the Customer.

your beans are configured correctly except for one bean :compositeItemReader

The read method of this bean is returning a String instead of a Customer which is because of this :

public class CompositeCursorItemReader implements ItemStreamReader {

/** Registered ItemStreamReaders. */
private List> cursorItemReaders;
/** Mandatory Unifying Mapper Implementation. */
private UnifyingItemsMapper unifyingMapper;

@Override
public T read() throws Exception, UnexpectedInputException, ParseException, NonTransientResourceException {
    // read from all registered readers
    List items = new ArrayList();
    for (AbstractCursorItemReader cursorItemReader : cursorItemReaders) {
        items.add(cursorItemReader.read());
    }
    // delegate to mapper
    return unifyingMapper.mapItems(items);
}
}

Its property UnifyingMapper is configured as follow:

here is the implementation of the UnifyingItemsMapper you are using:

 public class DefaultUnifyingStringItemsMapper implements UnifyingItemsMapper {

    /** {@inheritDoc} */
    @Override
    public String mapItems(List items) throws Exception {
        if (items != null && items.size() > 0) {
            StringBuilder sb = new StringBuilder();
            for (Object item : items) {
                if (item != null) {
                    sb.append(item);
                }
            }
            if (sb.length() > 0) {
                return sb.toString();
            } else {
                return null;
            }
        } else {
            return null;
        }
    }
}

the solution to this is to create a new Class that implements UnifyingItemsMapper and configure it for your CompositeCursorItemReader#unifyingMapper

Or just use your itemReader directly if you don't need a UnifyingItemsMapper: