# Discard

## Support Stereotypes

While item readers and writers serve as the main entry points for item-oriented processing, they might be supplemented by a number of support classes that perform specific tasks within the reader / writer lifecycle. These support stereotypes are useful for dividing the work of item readers and writers into reusable pieces, as well as abstracting away the details of processing, such as interaction with external systems. Additionally, they give us another opportunity to leverage the powerful configuration features of the Spring framework, as we can switch between several beans implementing these support interfaces without changing the driving item reader or writer.

### Item Transformers

An item transformer is a class that is capable of taking an object and changing it somehow before processing occurs. For instance, an item transformer my alter an object by changing its properties or by replacing it with another object entirely, such as a wrapper or derivative object. It can also be defined as an adaptor, allowing an object of one type to be converted for use as an object of a second type.