+++ /dev/null
-/*
- * Rhynodge - FileExistenceTrigger.java - Copyright © 2013 David Roden
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-
-package net.pterodactylus.rhynodge.triggers;
-
-import net.pterodactylus.rhynodge.Reaction;
-import net.pterodactylus.rhynodge.State;
-import net.pterodactylus.rhynodge.Trigger;
-import net.pterodactylus.rhynodge.output.DefaultOutput;
-import net.pterodactylus.rhynodge.output.Output;
-import net.pterodactylus.rhynodge.states.FileState;
-
-import com.google.common.base.Preconditions;
-
-/**
- * A trigger that detects changes in the existence of a file.
- *
- * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
- */
-public class FileExistenceTrigger implements Trigger {
-
- /** Whether a change is triggered. */
- private boolean triggered;
-
- //
- // TRIGGER METHODS
- //
-
- /**
- * {@inheritDoc}
- */
- @Override
- public State mergeStates(State previousState, State currentState) {
- Preconditions.checkState(previousState instanceof FileState, "previousState is not a FileState");
- Preconditions.checkState(currentState instanceof FileState, "currentState is not a FileState");
- triggered = ((FileState) previousState).exists() != ((FileState) currentState).exists();
- return currentState;
- }
-
- /**
- * {@inheritDoc}
- */
- @Override
- public boolean triggers() {
- return triggered;
- }
-
-}