DataPerspectiveResolver.java

/*
 * This file is part of SpongeAPI, licensed under the MIT License (MIT).
 *
 * Copyright (c) SpongePowered <https://www.spongepowered.org>
 * Copyright (c) contributors
 *
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 * 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
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 * 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
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package org.spongepowered.api.data;

import org.checkerframework.checker.nullness.qual.Nullable;
import org.spongepowered.api.data.value.Value;

public interface DataPerspectiveResolver<V extends Value<E>, E> {

    /**
     * Gets the {@link Key} this resolver supports.
     *
     * @return The key
     */
    Key<V> key();

    /**
     * When multiple plugins provide the same key this is used to
     * merge and pick the best.
     *
     * @return The merged value
     */
    E merge(Iterable<E> values);

    /**
     * When data holders value changes when looking at perspective of.
     *
     * @param dataHolder The data holder which value was overridden.
     * @param perspective The perspective it is perceived from.
     * @param value The value.
     */
    void apply(DataHolder dataHolder, DataPerspective perspective, @Nullable E value);
}