# Testing a generated mapper without Spring: Mappers.getMapper versus constructing the Impl


--- 1. Mappers.getMapper(...) ---
AddressMapper (no dependencies)   : AddressMapperImpl
CustomerMapper (uses = {...})      : RuntimeException
  root cause                      : java.lang.NoSuchMethodException: com.ankurm.mapstruct.mapper.CustomerMapperImpl.<init>()

--- 2. new CustomerMapperImpl(new AddressMapperImpl(), new OrderMapperImpl()) ---
no Spring, no reflection        : Asha Mehta