"BAEL-3407: Add examples for injecting Spring components in MapStruct" (#10778)

Co-authored-by: Krzysztof Woyke <krzysztof.woyke.sp@lhsystems.com>

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

@@ -0,0 +1,22 @@
+package com.baeldung.mapper;
+
+import com.baeldung.dto.SimpleSource;
+import com.baeldung.entity.SimpleDestination;
+import com.baeldung.service.SimpleService;
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.springframework.beans.factory.annotation.Autowired;
+
+@Mapper(componentModel = "spring")
+public abstract class SimpleDestinationMapperUsingInjectedService {
+
+    @Autowired
+    protected SimpleService simpleService;
+
+    @Mapping(target = "name", expression = "java(simpleService.enrichName(source.getName()))")
+    public abstract SimpleDestination sourceToDestination(SimpleSource source);
+
+    public abstract SimpleSource destinationToSource(SimpleDestination destination);
+
+
+}

mapstruct/src/main/java/com/baeldung/service/SimpleService.java

@@ -0,0 +1,11 @@
+package com.baeldung.service;
+
+import org.springframework.stereotype.Service;
+
+@Service
+public class SimpleService {
+
+    public String enrichName(String name) {
+        return "-:: " + name + " ::-";
+    }
+}

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

@@ -0,0 +1,35 @@
+package com.baeldung.mapper;
+
+import com.baeldung.dto.SimpleSource;
+import com.baeldung.entity.SimpleDestination;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration("classpath:applicationContext.xml")
+public class SimpleDestinationMapperUsingInjectedIntegrationTest {
+
+    @Autowired
+    private SimpleDestinationMapperUsingInjectedService mapper;
+
+    @Test
+    public void givenSourceToDestination_whenMaps_thenNameEnriched() {
+        // Given
+        SimpleSource source = new SimpleSource();
+        source.setName("Bob");
+        source.setDescription("The Builder");
+
+        // When
+        SimpleDestination destination = mapper.sourceToDestination(source);
+
+        // Then
+        assertThat(destination).isNotNull();
+        assertThat(destination.getName()).isEqualTo("-:: Bob ::-");
+        assertThat(destination.getDescription()).isEqualTo("The Builder");
+    }
+}