class Source1{
   List<String> customersIds;
   // getter and setter...
}
class Source2{
   Set<Integer> companyIds;
   // getter and setter...
}
class Source3{
   TreeSet<String> supplierIds;
   // getter and setter...
}

class Destination{
   @JMap(".*ids$")
   List<Integer> ids;
   // getter and setter...
}

...
import static com.googlecode.jmapper.api.JMapperAPI.*;
...
JMapperAPI jmapperAPI = new JMapperAPI()
    .add(mappedClass(Destination.class)
             .add(attribute("ids")
                     .value(".*ids$")));