What is it

Object that carries data between processes in order to reduce the number of method calls.

Objects that are safe to be transferred to the client as is.

• ready to be consumed by the client.

Detailed description

Each call to remote interface is expensive.

To reduce the number of calls, you need to transfer more data per call.

• One way to transfer more data is to use lot of parameters, but this is awkward to program (and not possible with languages such as Java that returns only a single value)

DTO holds all the data for the call.

• It serializes the data to go across the connection
• Usually an assembler is used in server to transfer data between the dTO and any domain objects
• Main advantage is to batch up multiple remote calls to a single call

Another advantage of DTO is encapsulating the serialization mechanism for transferring data over the wire

• By encapsulating the serialization, DTOs keep the logic out of the rest of the code and provide a clear point to change serialization