Bean Mapping of Transfer Objects

In the past years I have been working on multiple projects where the so-called Data Transfer Object (short DTO) pattern has been heavily used. This is a pattern that has even been a core pattern in the JEE world. This pattern certainly has its justification for the right cases. But in many cases I have seen it applied inappropriately. This blog posting by Adam Bien, a JEE advocate, is outlining the case where it should be considered useful. However when applied, this pattern comes at the cost of additional code to maintain and some extra CPU cycles for doing the mapping.