EventSubscriber.java

/*
 * This file is part of NucleusFramework for Bukkit, licensed under the MIT License (MIT).
 *
 * Copyright (c) JCThePants (www.jcwhatever.com)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

package com.jcwhatever.nucleus.utils.observer.event;

import com.jcwhatever.nucleus.utils.PreCon;
import com.jcwhatever.nucleus.utils.observer.Subscriber;
import javax.annotation.Nullable;

/**
 * An event subscriber "delegate".
 */
public abstract class EventSubscriber<E> extends Subscriber implements IEventSubscriber<E> {

    private EventSubscriberPriority _priority = EventSubscriberPriority.NORMAL;
    private boolean _isInvokedForCancelled;

    @Override
    public abstract void onEvent(@Nullable Object caller, E event);

    @Override
    public EventSubscriberPriority getPriority() {
        return _priority;
    }

    public <T extends EventSubscriber> T setPriority(EventSubscriberPriority priority) {
        PreCon.notNull(priority);

        _priority = priority;

        @SuppressWarnings("unchecked")
        T self = (T)this;
        return self;
    }

    @Override
    public boolean isInvokedForCancelled() {
        return _isInvokedForCancelled;
    }

    public <T extends EventSubscriber> T setInvokedForCancelled(boolean isIgnored) {
        _isInvokedForCancelled = isIgnored;

        @SuppressWarnings("unchecked")
        T self = (T)this;
        return self;
    }

    @Override
    public int compareTo(IEventSubscriber<E> o) {
        synchronized (getSync()) {
            return Integer.compare(getPriority().getSortOrder(), o.getPriority().getSortOrder());
        }
    }
}