SmartTimer.java

/*
 * Copyright (c) 2022, Gluon
 *
 * 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/>.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL GLUON BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.gluonhq.richtextarea;

import java.util.Objects;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;

class SmartTimer {

    private ScheduledExecutorService scheduler;
    private ScheduledFuture<?> scheduledTask;
    private final Runnable task;
    private final long delay;
    private final long period;

    public SmartTimer( Runnable task, long delay, long period) {
        this.task = Objects.requireNonNull(task);
        this.delay = delay;
        this.period = period;
    }

    public void pause() {
        if (scheduledTask != null) {
            scheduledTask.cancel(true);
            scheduledTask = null;
        }
        if (scheduler != null) {
            scheduler.shutdownNow();
            scheduler = null;
        }
    }

    public void start( ) {
        if (scheduler == null || scheduler.isShutdown()) {
            scheduler = Executors.newSingleThreadScheduledExecutor(r -> {
                Thread t = new Thread(r);
                t.setDaemon(true);
                return t;
            });
            scheduledTask = scheduler.scheduleAtFixedRate(task, delay, period, TimeUnit.MILLISECONDS);
        }
    }


}