Sortable.java

  1. /*
  2.  * *************************************************************************************************************************************************************
  3.  *
  4.  * TheseFoolishThings: Miscellaneous utilities
  5.  * http://tidalwave.it/projects/thesefoolishthings
  6.  *
  7.  * Copyright (C) 2009 - 2025 by Tidalwave s.a.s. (http://tidalwave.it)
  8.  *
  9.  * *************************************************************************************************************************************************************
  10.  *
  11.  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
  12.  * You may obtain a copy of the License at
  13.  *
  14.  *     http://www.apache.org/licenses/LICENSE-2.0
  15.  *
  16.  * 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
  17.  * CONDITIONS OF ANY KIND, either express or implied.  See the License for the specific language governing permissions and limitations under the License.
  18.  *
  19.  * *************************************************************************************************************************************************************
  20.  *
  21.  * git clone https://bitbucket.org/tidalwave/thesefoolishthings-src
  22.  * git clone https://github.com/tidalwave-it/thesefoolishthings-src
  23.  *
  24.  * *************************************************************************************************************************************************************
  25.  */
  26. package it.tidalwave.role;

  27. import javax.annotation.Nonnull;
  28. import it.tidalwave.util.Finder;
  29. import it.tidalwave.util.Finder.SortCriterion;
  30. import it.tidalwave.util.Finder.SortDirection;

  31. /***************************************************************************************************************************************************************
  32.  *
  33.  * The role of an object that has contents that can be sorted.
  34.  *
  35.  * @author  Fabrizio Giudici
  36.  * @it.tidalwave.javadoc.stable
  37.  *
  38.  **************************************************************************************************************************************************************/
  39. public interface Sortable
  40.   {
  41.     public static final Class<Sortable> _Sortable_ = Sortable.class;

  42.     /***********************************************************************************************************************************************************
  43.      * A default {@code Sortable} which does nothing (useful for implementing the NullObject pattern). This object always returns
  44.      * {@link SortCriterion#UNSORTED} as {@code sortCriterion} and {@link SortDirection#ASCENDING} as {@code sortDirection}.
  45.      **********************************************************************************************************************************************************/
  46.     public static final Sortable DEFAULT = new Sortable()
  47.       {
  48.         @Override
  49.         public void setSortCriterion (@Nonnull final SortCriterion sortCriterion)
  50.           {
  51.           }

  52.         @Override @Nonnull
  53.         public SortCriterion getSortCriterion()
  54.           {
  55.             return Finder.SortCriterion.UNSORTED;
  56.           }

  57.         @Override
  58.         public void setSortDirection (@Nonnull final SortDirection sortDirection)
  59.           {
  60.           }

  61.         @Override @Nonnull
  62.         public SortDirection getSortDirection()
  63.           {
  64.             return SortDirection.ASCENDING;
  65.           }
  66.       };

  67.     /***********************************************************************************************************************************************************
  68.      * Sets the sort criterion.
  69.      * @param sortCriterion  the sort criterion
  70.      **********************************************************************************************************************************************************/
  71.     @SuppressWarnings("EmptyMethod")
  72.     public void setSortCriterion (@Nonnull SortCriterion sortCriterion);

  73.     /***********************************************************************************************************************************************************
  74.      * Sets the sort direction.
  75.      * @param sortDirection  the sort direction
  76.      **********************************************************************************************************************************************************/
  77.     @SuppressWarnings("EmptyMethod")
  78.     public void setSortDirection (@Nonnull SortDirection sortDirection);

  79.     /***********************************************************************************************************************************************************
  80.      * Returns the current sort criterion.
  81.      * @return  the sort criterion
  82.      **********************************************************************************************************************************************************/
  83.     @Nonnull @SuppressWarnings("SameReturnValue")
  84.     public SortCriterion getSortCriterion();

  85.     /***********************************************************************************************************************************************************
  86.      * Returns the current sort direction.
  87.      * @return  the sort direction
  88.      **********************************************************************************************************************************************************/
  89.     @Nonnull @SuppressWarnings("SameReturnValue")
  90.     public SortDirection getSortDirection();
  91.   }