BAEL-6572: Added examples and test for conditional mapping using mapstruct

mapstruct/src/main/java/com/baeldung/expression/dto/LicenseDto.java

@@ -0,0 +1,21 @@
+package com.baeldung.expression.dto;
+
+import java.time.LocalDateTime;
+import java.util.UUID;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+
+@AllArgsConstructor
+@Data
+@Builder
+public class LicenseDto {
+
+    private UUID id;
+
+    private LocalDateTime startDate;
+
+    private LocalDateTime endDate;
+
+}

mapstruct/src/main/java/com/baeldung/expression/mapper/LicenseMapper.java

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+package com.baeldung.expression.mapper;
+
+import java.time.Duration;
+import java.time.LocalDateTime;
+import java.time.OffsetDateTime;
+import java.time.ZoneOffset;
+
+import org.mapstruct.AfterMapping;
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.mapstruct.MappingTarget;
+
+import com.baeldung.expression.dto.LicenseDto;
+import com.baeldung.expression.model.License;
+
+@Mapper
+public interface LicenseMapper {
+
+    @Mapping(target = "startDate", expression = "java(mapStartDate(licenseDto))")
+    @Mapping(target = "endDate", ignore = true)
+    @Mapping(target = "active", constant = "true")
+    @Mapping(target = "renewalRequired", conditionExpression = "java(isEndDateInTwoWeeks(licenseDto))", source = ".")
+    License toLicense(LicenseDto licenseDto);
+
+    @AfterMapping
+    default void afterMapping(LicenseDto licenseDto, @MappingTarget License license) {
+        OffsetDateTime endDate = licenseDto.getEndDate() != null ? licenseDto.getEndDate()
+            .atOffset(ZoneOffset.UTC) : OffsetDateTime.now()
+            .plusYears(1);
+        license.setEndDate(endDate);
+    }
+
+    default OffsetDateTime mapStartDate(LicenseDto licenseDto) {
+        return licenseDto.getStartDate() != null ? licenseDto.getStartDate()
+            .atOffset(ZoneOffset.UTC) : OffsetDateTime.now();
+    }
+
+    default boolean isEndDateInTwoWeeks(LicenseDto licenseDto) {
+        return licenseDto.getEndDate() != null && Duration.between(licenseDto.getEndDate(), LocalDateTime.now())
+            .toDays() <= 14;
+    }
+
+}

mapstruct/src/main/java/com/baeldung/expression/model/License.java

@@ -0,0 +1,21 @@
+package com.baeldung.expression.model;
+
+import java.time.OffsetDateTime;
+import java.util.UUID;
+
+import lombok.Data;
+
+@Data
+public class License {
+
+    private UUID id;
+
+    private OffsetDateTime startDate;
+
+    private OffsetDateTime endDate;
+
+    private boolean active;
+
+    private boolean renewalRequired;
+
+}

mapstruct/src/test/java/com/baeldung/expression/mapper/LicenseMapperUnitTest.java

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+package com.baeldung.expression.mapper;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+
+import org.junit.jupiter.api.Test;
+import org.mapstruct.factory.Mappers;
+
+import com.baeldung.expression.dto.LicenseDto;
+import com.baeldung.expression.model.License;
+
+class LicenseMapperUnitTest {
+
+    LicenseMapper licenseMapper = Mappers.getMapper(LicenseMapper.class);
+
+    @Test
+    void givenLicenseDtoWithStartDateAndWithoutEndDate_ThenLicenseShouldBePopulatedWithDefaultEndDate() {
+        License license = licenseMapper.toLicense(LicenseDto.builder()
+            .startDate(LocalDateTime.now())
+            .build());
+        assertThat(license).isNotNull()
+            .satisfies(l -> {
+                assertThat(l.getStartDate()
+                    .toLocalDate()).isEqualTo(LocalDate.now());
+                assertThat(l.getEndDate()
+                    .toLocalDate()).isEqualTo(LocalDate.now()
+                    .plusYears(1));
+            });
+    }
+
+    @Test
+    void givenLicenseDtoWithEndDateAndWithoutStartDate_ThenLicenseShouldBePopulatedWithDefaultStartDate() {
+        License license = licenseMapper.toLicense(LicenseDto.builder()
+            .endDate(LocalDateTime.now()
+                .plusYears(2))
+            .build());
+        assertThat(license).isNotNull()
+            .satisfies(l -> {
+                assertThat(l.getStartDate()
+                    .toLocalDate()).isEqualTo(LocalDate.now());
+                assertThat(l.getEndDate()
+                    .toLocalDate()).isEqualTo(LocalDate.now()
+                    .plusYears(2));
+            });
+    }
+
+    @Test
+    void givenLicenseDtoWithoutEndDateAndWithoutStartDate_ThenLicenseShouldBePopulatedWithDefaultStartDateAndEndDate() {
+        License license = licenseMapper.toLicense(LicenseDto.builder()
+            .build());
+        assertThat(license).isNotNull()
+            .satisfies(l -> {
+                assertThat(l.getStartDate()
+                    .toLocalDate()).isEqualTo(LocalDate.now());
+                assertThat(l.getEndDate()
+                    .toLocalDate()).isEqualTo(LocalDate.now()
+                    .plusYears(1));
+            });
+    }
+
+    @Test
+    void givenLicenseDtoWithoutStartDateAndEndDate_ThenLicenseShouldBePopulatedWithDefaultDetails() {
+        License license = licenseMapper.toLicense(LicenseDto.builder()
+            .build());
+        assertThat(license).isNotNull()
+            .satisfies(l -> {
+                assertThat(l.getStartDate()
+                    .toLocalDate()).isEqualTo(LocalDate.now());
+                assertThat(l.getEndDate()
+                    .toLocalDate()).isEqualTo(LocalDate.now()
+                    .plusYears(1));
+                assertThat(l.isActive()).isTrue();
+                assertThat(l.isRenewalRequired()).isFalse();
+            });
+    }
+
+    @Test
+    void givenLicenseDtoWithEndDateInTwoWeeks_ThenLicenseShouldBePopulatedWithReminderSetToTrue() {
+        License license = licenseMapper.toLicense(LicenseDto.builder()
+            .endDate(LocalDateTime.now()
+                .plusDays(10))
+            .build());
+        assertThat(license).isNotNull()
+            .satisfies(l -> {
+                assertThat(l.getStartDate()
+                    .toLocalDate()).isEqualTo(LocalDate.now());
+                assertThat(l.getEndDate()
+                    .toLocalDate()).isEqualTo(LocalDate.now()
+                    .plusDays(10));
+                assertThat(l.isActive()).isTrue();
+                assertThat(l.isRenewalRequired()).isTrue();
+            });
+    }
+
+}