Implementation of category creation.

codiki-domain/src/main/java/org/codiki/domain/category/exception/CategoryEditionException.java

@@ -0,0 +1,13 @@
+package org.codiki.domain.category.exception;
+
+import org.codiki.domain.exception.FunctionnalException;
+
+public class CategoryEditionException extends FunctionnalException {
+    public CategoryEditionException(String reason) {
+        super(String.format("Impossible to edit a category because : %s.", reason));
+    }
+
+    public CategoryEditionException(FunctionnalException cause) {
+        super("Impossible to edit a category due to a root cause.", cause);
+    }
+}

codiki-domain/src/main/java/org/codiki/domain/category/model/builder/CategoryBuilder.java

@@ -0,0 +1,46 @@
+package org.codiki.domain.category.model.builder;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
+
+import org.codiki.domain.category.model.Category;
+
+public class CategoryBuilder {
+    private UUID id;
+    private String name;
+    private List<Category> subCategories;
+
+    public static CategoryBuilder aCategory() {
+        return new CategoryBuilder();
+    }
+
+    private CategoryBuilder() {}
+
+    public CategoryBuilder withId(UUID id) {
+        this.id = id;
+        return this;
+    }
+
+    public CategoryBuilder withName(String name) {
+        this.name = name;
+        return this;
+    }
+
+    public CategoryBuilder withSubCategories(List<Category> subCategories) {
+        this.subCategories = subCategories;
+        return this;
+    }
+
+    public CategoryBuilder withSubCategory(Category subCategory) {
+        if (subCategories == null) {
+            subCategories = new ArrayList<>();
+        }
+        subCategories.add(subCategory);
+        return this;
+    }
+
+    public Category build() {
+        return new Category(id, name, subCategories);
+    }
+}

codiki-domain/src/main/java/org/codiki/domain/category/port/CategoryPort.java

@@ -1,10 +1,15 @@
 package org.codiki.domain.category.port;
 
+import java.util.List;
 import java.util.Optional;
 import java.util.UUID;
 
 import org.codiki.domain.category.model.Category;
 
 public interface CategoryPort {
-    Optional<Category> findById(final UUID uuid);
+    Optional<Category> findById(UUID uuid);
+
+    void save(Category category);
+
+    List<Category> findAllByIds(List<UUID> subCategoryIds);
 }