It is indeed obvious what you are trying to achieve. However, the implementation for something like this is not entirely straightforward. MapStruct does not have support for this because and it is not as easy as you might think. How can MapStruct know what should be considered as a key and value for the Target?

I would suggest following #1075 which will add support for mapping from Map into some bean. Your use case is still not covered by that, but you can convert your List<Property> into a Map and then do the mapping.

For the time being you have to do that mapping by hand.

@filiphr , I was not expecting MapStruct to find keys and values automatically. That code would have to be implemented by the user on a method with the list as source and the target class as target (parameters), just as I stated on the example above. I believe this wouldn't be hard at all, right?

So you are looking for the code to invoke mapProperties for you?

I would actually suggest something else here. You can do the exact same thing in @AfterMapping / @BeforeMapping.

e.g.

public abstract Target convert(Source source);

@AfterMapping
public void mapProperties(Source source, @MappingTarget Target target) {
    List<Properties> properties = source.getProperties();
    //(and then some mapping code here)
}

I guess that works.

Thanks for the help