GroupByParent.transformCategories(): extract method from CategoryServiceImpl.

Also rename original method.

Addressed to #592

No functional changes.

Author: php-coder

src/main/java/ru/mystamps/web/controller/SeriesController.java

@@ -63,6 +63,7 @@
 import ru.mystamps.web.controller.dto.AddSeriesSalesForm;
 import ru.mystamps.web.controller.dto.NullableImageUrl;
 import ru.mystamps.web.controller.interceptor.DownloadImageInterceptor;
+import ru.mystamps.web.dao.dto.CategoryDto;
 import ru.mystamps.web.dao.dto.LinkEntityDto;
 import ru.mystamps.web.dao.dto.PurchaseAndSaleDto;
 import ru.mystamps.web.dao.dto.SeriesInfoDto;
@@ -137,8 +138,11 @@ public void showForm(
 
 		String lang = LocaleUtils.getLanguageOrNull(userLocale);
 
-		List<FirstLevelCategoryDto> categories = categoryService.findFirstLevelCategories(lang);
-		model.addAttribute("categories", categories);
+		List<CategoryDto> categories =
+			categoryService.findCategoriesWithParents(lang);
+		List<FirstLevelCategoryDto> groupedCategories =
+			GroupByParent.transformCategories(categories);
+		model.addAttribute("categories", groupedCategories);
 
 		List<LinkEntityDto> countries = countryService.findAllAsLinkEntities(lang);
 		model.addAttribute("countries", countries);
@@ -229,8 +233,11 @@ public String processInput(
 		if (result.hasErrors()) {
 			String lang = LocaleUtils.getLanguageOrNull(userLocale);
 
-			List<FirstLevelCategoryDto> categories = categoryService.findFirstLevelCategories(lang);
-			model.addAttribute("categories", categories);
+			List<CategoryDto> categories =
+				categoryService.findCategoriesWithParents(lang);
+			List<FirstLevelCategoryDto> groupedCategories =
+				GroupByParent.transformCategories(categories);
+			model.addAttribute("categories", groupedCategories);
 
 			List<LinkEntityDto> countries = countryService.findAllAsLinkEntities(lang);
 			model.addAttribute("countries", countries);

src/main/java/ru/mystamps/web/service/CategoryService.java

@@ -21,17 +21,17 @@
 import java.util.List;
 import java.util.Set;
 
+import ru.mystamps.web.dao.dto.CategoryDto;
 import ru.mystamps.web.dao.dto.LinkEntityDto;
 import ru.mystamps.web.service.dto.AddCategoryDto;
-import ru.mystamps.web.service.dto.FirstLevelCategoryDto;
 
 @SuppressWarnings("PMD.TooManyMethods")
 public interface CategoryService {
 	String add(AddCategoryDto dto, Integer userId);
 	List<Integer> findIdsByNames(Set<String> names);
 	List<Integer> findIdsWhenNameStartsWith(String name);
 	List<LinkEntityDto> findAllAsLinkEntities(String lang);
-	List<FirstLevelCategoryDto> findFirstLevelCategories(String lang);
+	List<CategoryDto> findCategoriesWithParents(String lang);
 	LinkEntityDto findOneAsLinkEntity(String slug, String lang);
 	long countAll();
 	long countCategoriesOf(Integer collectionId);

src/main/java/ru/mystamps/web/service/CategoryServiceImpl.java

@@ -17,7 +17,6 @@
  */
 package ru.mystamps.web.service;
 
-import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Date;
 import java.util.List;
@@ -40,7 +39,6 @@
 import ru.mystamps.web.dao.dto.CategoryDto;
 import ru.mystamps.web.dao.dto.LinkEntityDto;
 import ru.mystamps.web.service.dto.AddCategoryDto;
-import ru.mystamps.web.service.dto.FirstLevelCategoryDto;
 import ru.mystamps.web.support.spring.security.HasAuthority;
 import ru.mystamps.web.util.LocaleUtils;
 import ru.mystamps.web.util.SlugUtils;
@@ -117,42 +115,8 @@ public List<LinkEntityDto> findAllAsLinkEntities(String lang) {
 	@Override
 	@Transactional(readOnly = true)
 	@PreAuthorize(HasAuthority.CREATE_SERIES)
-	@SuppressWarnings("PMD.AvoidInstantiatingObjectsInLoops")
-	public List<FirstLevelCategoryDto> findFirstLevelCategories(String lang) {
-		List<CategoryDto> categories = categoryDao.findCategoriesWithParents(lang);
-		if (categories.isEmpty()) {
-			return Collections.emptyList();
-		}
-		
-		// Because of Thymeleaf's restrictions we can't return categories as-is and need this
-		// transformation
-		List<FirstLevelCategoryDto> items = new ArrayList<>();
-		String lastParent = null;
-		FirstLevelCategoryDto lastItem = null;
-		
-		for (CategoryDto category : categories) {
-			String name   = category.getName();
-			String slug   = category.getSlug();
-			String parent = category.getParentName();
-			
-			boolean categoryWithoutParent = parent == null;
-			boolean createNewItem = categoryWithoutParent || !parent.equals(lastParent);
-			
-			if (createNewItem) {
-				lastParent = parent;
-				if (categoryWithoutParent) {
-					lastItem = new FirstLevelCategoryDto(slug, name);
-				} else {
-					lastItem = new FirstLevelCategoryDto(parent);
-					lastItem.addChild(slug, name);
-				}
-				items.add(lastItem);
-			} else {
-				lastItem.addChild(slug, name);
-			}
-		}
-		
-		return items;
+	public List<CategoryDto> findCategoriesWithParents(String lang) {
+		return categoryDao.findCategoriesWithParents(lang);
 	}
 
 	@Override

src/main/java/ru/mystamps/web/support/thymeleaf/GroupByParent.java

@@ -21,7 +21,9 @@
 import java.util.Collections;
 import java.util.List;
 
+import ru.mystamps.web.dao.dto.CategoryDto;
 import ru.mystamps.web.dao.dto.TransactionParticipantDto;
+import ru.mystamps.web.service.dto.FirstLevelCategoryDto;
 import ru.mystamps.web.service.dto.GroupedTransactionParticipantDto;
 
 /**
@@ -72,4 +74,39 @@ public static List<GroupedTransactionParticipantDto> transformParticipants(
 		return items;
 	}
 
+	@SuppressWarnings("PMD.AvoidInstantiatingObjectsInLoops")
+	public static List<FirstLevelCategoryDto> transformCategories(List<CategoryDto> categories) {
+		if (categories.isEmpty()) {
+			return Collections.emptyList();
+		}
+		
+		List<FirstLevelCategoryDto> items = new ArrayList<>();
+		String lastParent = null;
+		FirstLevelCategoryDto lastItem = null;
+		
+		for (CategoryDto category : categories) {
+			String name   = category.getName();
+			String slug   = category.getSlug();
+			String parent = category.getParentName();
+			
+			boolean categoryWithoutParent = parent == null;
+			boolean createNewItem = categoryWithoutParent || !parent.equals(lastParent);
+			
+			if (createNewItem) {
+				lastParent = parent;
+				if (categoryWithoutParent) {
+					lastItem = new FirstLevelCategoryDto(slug, name);
+				} else {
+					lastItem = new FirstLevelCategoryDto(parent);
+					lastItem.addChild(slug, name);
+				}
+				items.add(lastItem);
+			} else {
+				lastItem.addChild(slug, name);
+			}
+		}
+		
+		return items;
+	}
+	
 }