AutoMapper VS Mapster

AutoMapper

The 13.0 Upgrade Guide page was created back in April, but there is no sign of the release yet.

The most well-know is probably AutoMapper, but it's not universally liked.

AutoMapper - well for automapping

When working with AutoMapper, we often bump into runtime errors due to invalid mapping configuration, such as this one:

What problems will resolve automapper?

If you are a fan of data mappers, you might want to enhance the implementation with additional extension methods. Here is an example for AutoMapper.

I'm wondering myself. Most mappers like https://automapper.org/ will make a best effort mapper automatically via introspection. If this is just a DSL/annotation suite that requires explicit, complete mapping implementations then this strikes me as a re-implementation of parts of kotlin in kotlin.

🔴 [Mapster] A fast, fun and stimulating object to object Mapper! Mapster was designed to be efficient on both speed and memory. You could gain a 4x performance improvement whilst using only 1/3 of memory.

Mapster

Have you read this part in their documentation? https://github.com/MapsterMapper/Mapster/wiki/Data-types

Which is the main reason I don't use it anymore. I can still stand behind why it was created and what it was trying to solve. If you still want to use a mapper I would recommend Mapster as it supports source generation so you can see all code and it's references.

Gotta add a shoutout to Mapster which does pretty much the same thing also using source generation.

I highly recommend Mapster (https://github.com/MapsterMapper/Mapster)

We use Mapster coupled with FastExpressionCompiler and have been very happy with it.

Try Mapster

I hope I managed to convince you and proved the value of unit tests for mappings, so let's move on to the next example. We're going to use AutoMapper, but from a testing standpoint, the choice of mapper makes no difference. For instance, we can replace AutoMapper with Mapster and it won't affect our tests in any way. Moreover, the existing tests will indicate whether our mapping refactoring was successful or not, which is one of the points of having unit tests 🙂