2 * rhynodge - ComicMerger.java - Copyright © 2013–2021 David Roden
4 * This program is free software: you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation, either version 3 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 package net.pterodactylus.rhynodge.mergers;
20 import java.util.ArrayList;
21 import java.util.HashSet;
22 import java.util.List;
24 import javax.annotation.Nonnull;
26 import net.pterodactylus.rhynodge.Merger;
27 import net.pterodactylus.rhynodge.State;
28 import net.pterodactylus.rhynodge.states.ComicState;
29 import net.pterodactylus.rhynodge.states.ComicState.Comic;
31 import static com.google.common.base.Preconditions.checkArgument;
34 * {@link Merger} implementation that merger two {@link ComicState}s.
36 * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
38 public class ComicMerger implements Merger {
42 public State mergeStates(@Nonnull State previousState, @Nonnull State currentState) {
43 checkArgument(previousState instanceof ComicState, "previous state must be a comic state");
44 checkArgument(currentState instanceof ComicState, "current state must be a comic state");
46 ComicState previousComicState = (ComicState) previousState;
47 ComicState currentComicState = (ComicState) currentState;
49 List<Comic> allComics = new ArrayList<>(previousComicState.comics());
50 Set<Comic> newComics = new HashSet<>();
52 for (Comic comic : currentComicState) {
53 if (!allComics.contains(comic)) {
59 return new ComicState(allComics, newComics);