001package com.pi4j.io.gpio.tasks.impl;
002
003/*
004 * #%L
005 * **********************************************************************
006 * ORGANIZATION  :  Pi4J
007 * PROJECT       :  Pi4J :: Java Library (Core)
008 * FILENAME      :  GpioEventDebounceTaskImpl.java
009 *
010 * This file is part of the Pi4J project. More information about
011 * this project can be found here:  https://www.pi4j.com/
012 * **********************************************************************
013 * %%
014 * Copyright (C) 2012 - 2021 Pi4J
015 * %%
016 * This program is free software: you can redistribute it and/or modify
017 * it under the terms of the GNU Lesser General Public License as
018 * published by the Free Software Foundation, either version 3 of the
019 * License, or (at your option) any later version.
020 *
021 * This program is distributed in the hope that it will be useful,
022 * but WITHOUT ANY WARRANTY; without even the implied warranty of
023 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
024 * GNU General Lesser Public License for more details.
025 *
026 * You should have received a copy of the GNU General Lesser Public
027 * License along with this program.  If not, see
028 * <http://www.gnu.org/licenses/lgpl-3.0.html>.
029 * #L%
030 */
031
032
033import com.pi4j.io.gpio.GpioFactory;
034import com.pi4j.io.gpio.GpioPinDigitalInput;
035import com.pi4j.io.gpio.PinState;
036import com.pi4j.io.gpio.event.PinDigitalStateChangeEvent;
037
038import java.util.concurrent.ExecutorService;
039
040public class GpioEventDebounceTaskImpl implements Runnable {
041
042    private final GpioPinDigitalInput pin;
043    private final PinState originalPinState;
044    private static ExecutorService executor;
045
046    public GpioEventDebounceTaskImpl(GpioPinDigitalInput pin, PinState state) {
047        executor = GpioFactory.getExecutorServiceFactory().getGpioEventExecutorService();
048        this.originalPinState = state;
049        this.pin = pin;
050    }
051
052    @Override
053    public void run() {
054        // if the current pin state is not the same as the original pin state,
055        // then we need to raise a new pin event to notify the user that the pin
056        // state has changed during the debounce delay period
057        if(!pin.isState(originalPinState)){
058            // add a new pin event notification to the thread pool for *immediate* execution
059            executor.execute(new GpioEventDispatchTaskImpl(pin,
060                    new PinDigitalStateChangeEvent(this, pin.getPin(), pin.getState())));
061        }
062    }
063}