Bael 7725 (#18705)

* BAEL-7725

* update to use junit assert

---------

Co-authored-by: Wynn Teo <wynnteo@Wynns-MacBook-Pro.local>

Author: wynnteo

mapstruct/src/main/java/com/baeldung/context/MappingContext.java

@@ -0,0 +1,9 @@
+package com.baeldung.context;
+
+public class MappingContext {
+
+    public String normalizeName(String name) {
+        return name == null ? null : name.trim()
+            .toUpperCase();
+    }
+}

mapstruct/src/main/java/com/baeldung/mapper/CustomerDtoMapper.java

@@ -1,8 +1,12 @@
 package com.baeldung.mapper;
 
+import org.mapstruct.AfterMapping;
+import org.mapstruct.Context;
 import org.mapstruct.Mapper;
 import org.mapstruct.Mapping;
+import org.mapstruct.MappingTarget;
 
+import com.baeldung.context.MappingContext;
 import com.baeldung.dto.CustomerDto;
 import com.baeldung.entity.Customer;
 
@@ -12,4 +16,14 @@ public interface CustomerDtoMapper {
     @Mapping(source = "firstName", target = "forename")
     @Mapping(source = "lastName", target = "surname")
     CustomerDto from(Customer customer);
+
+    @Mapping(source = "firstName", target = "forename")
+    @Mapping(source = "lastName", target = "surname")
+    CustomerDto from(Customer customer, @Context MappingContext context);
+
+    @AfterMapping
+    default void normalize(@MappingTarget CustomerDto dto, @Context MappingContext context) {
+        dto.setForename(context.normalizeName(dto.getForename()));
+        dto.setSurname(context.normalizeName(dto.getSurname()));
+    }
 }

mapstruct/src/test/java/com/baeldung/mapper/CustomerDtoMapperUnitTest.java

@@ -5,6 +5,7 @@
 import org.junit.jupiter.api.Test;
 import org.mapstruct.factory.Mappers;
 
+import com.baeldung.context.MappingContext;
 import com.baeldung.dto.CustomerDto;
 import com.baeldung.entity.Customer;
 
@@ -26,4 +27,15 @@ void testGivenCustomer_mapsToCustomerDto() {
         assertEquals(customerDto.getForename(), customer.getFirstName());
         assertEquals(customerDto.getSurname(), customer.getLastName());
     }
+
+    @Test
+    void givenCustomer_whenMappedUsingContext_thenReturnsFormattedDto() {
+        Customer customer = new Customer();
+        customer.setFirstName(" max ");
+        customer.setLastName(" powers ");
+        MappingContext context = new MappingContext();
+        CustomerDto dto = customerDtoMapper.from(customer, context);
+        assertEquals("MAX", dto.getForename());
+        assertEquals("POWERS", dto.getSurname());
+    }
 }