content: /*
   *  Licensed to the Apache Software Foundation (ASF) under one
   *  or more contributor license agreements.  See the NOTICE file
   *  distributed with this work for additional information
   *  regarding copyright ownership.  The ASF licenses this file
   *  to you under the Apache License, Version 2.0 (the
   *  "License"); you may not use this file except in compliance
   *  with the License.  You may obtain a copy of the License at
   *
   *        http://www.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing,
   *  software distributed under the License is distributed on an
   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   *  KIND, either express or implied.  See the License for the
   *  specific language governing permissions and limitations
   *  under the License.
   */
  package org.apache.causeway.extensions.excel.fixtures.demoapp.todomodule.dom;
  
  import java.util.Collections;
  import java.util.List;
  import java.util.function.Predicate;
  
  public enum Subcategory {
      // professional
      OpenSource, Consulting, Education, Marketing,
      // domestic
      Shopping, Housework, Garden, Chores,
      // other
      Other;
  
      public static List<Subcategory> listFor(final Category category) {
          return category != null ? category.subcategories() : Collections.<Subcategory>emptyList();
      }
  
      public static String validate(final Category category, final Subcategory subcategory) {
          if (category == null) {
              return "Enter category first";
          }
          return !category.subcategories().contains(subcategory)
                  ? "Invalid subcategory for category '" + category + "'"
                  : null;
      }
  
      public static Predicate<Subcategory> thoseFor(final Category category) {
          return subcategory -> category.subcategories().contains(subcategory);
      }
  }
  