Decorate mapping operations with additional logic.
In some use cases mapping fields is not enough. Sometimes we need to add additional logic to the mapping. For these use cases we have the decorators, the decorators allow us to perform operations on our models after the mapping has finished.
We start with our two classes, our source class User and our destination class UserDisplay.
data class User(
var firstName: String,
var lastName: String
)public class User {
private String firstName;
private String lastName;
public String getFirstName() {
return firstName;
}
data class UserDisplay(
var firstName: String,
var lastName: String,
var fullName: String
)public class UserDisplay {
private String firstName;
private String lastName;
private String fullName;
public String getFirstName() {
In this example, we want to merge the firstName and lastName fields to the fullName field.
Adding decorators is available through the ShapeShiftBuilder class. Decorators can be added inline or as a separate class.
To create a decorator class implement the MappingDecorator interface.
And register it to the ShapeShift instance.
It is also possible to add the decorator logic inline.
class UserUserDisplayDecorator : MappingDecorator<User, UserDisplay> {
override fun decorate(context: MappingDecoratorContext<User, UserDisplay>) {
val (from, to) = context
to.fullName = "${from.firstName} ${from.lastName}"
}
}public class UserUserDisplayDecorator implements MappingDecorator<User, UserDisplay> {
@Override
public void decorate(@NonNull MappingDecoratorContext<User, UserDisplay> mappingDecoratorContext) {
User from = mappingDecoratorContext.getFrom();
UserDisplay to = mappingDecoratorContext.getTo();
to.setFullName(from.getFirstName() + " " + from.getLastName());
}
}val shapeShift = ShapeShiftBuilder()
.withDecorator(UserUserDisplayDecorator())
.build()ShapeShift shapeShift = new ShapeShiftBuilder()
.withDecorator(User.class, UserDisplay.class, new UserUserDisplayDecorator())
.build();val shapeShift = ShapeShiftBuilder()
.withDecorator(MappingDecorator<User, UserDisplay> {
val (from, to) = it
to.fullName = "${from.firstName} ${from.lastName}"
})
.build()ShapeShift shapeShift = new ShapeShiftBuilder()
.withDecorator(User.class, UserDisplay.class, mappingDecoratorContext -> {
User from = mappingDecoratorContext.getFrom();
UserDisplay to = mappingDecoratorContext.getTo();
to.setFullName(from.getFirstName() + " " + from.getLastName());
})
.build();