neon.client.ComponentManager.java Source code

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Here is the source code for neon.client.ComponentManager.java

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/*
 *   Neon, a roguelike engine.
 *   Copyright (C) 2018 - Maarten Driesen
 * 
 *   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 neon.client;

import com.google.common.collect.ClassToInstanceMap;
import com.google.common.collect.HashBasedTable;
import com.google.common.collect.ImmutableClassToInstanceMap;
import com.google.common.collect.Table;

import neon.common.entity.components.Component;

/**
 * A table containing all components for all currently loaded entities.
 * 
 * @author mdriesen
 *
 */
public final class ComponentManager {
    private final Table<Long, Class<? extends Component>, Component> components = HashBasedTable.create();

    /**
     * Puts a component in the table.
     * 
     * @param component   the component to add
     */
    public void putComponent(Component component) {
        components.put(component.getEntity(), component.getClass(), component);
    }

    /**
     * Removes an entity from the table.
     * 
     * @param uid   the uid of an entity
     */
    public void removeEntity(long uid) {
        components.row(uid).clear();
    }

    /**
     * 
     * @param uid   the uid of an entity
     * @param type   the type of a component
     * @return   a component of the given type for the given entity
     */
    public <T extends Component> T getComponent(long uid, Class<T> type) {
        return type.cast(components.get(uid, type));
    }

    /**
     * Checks whether an entity has a certain component type.
     * 
     * @param uid   the uid of an entity
     * @param type   the type of the component
     * @return
     */
    public boolean hasComponent(long uid, Class<?> type) {
        return components.contains(uid, type);
    }

    /**
     * 
     * @param uid
     * @return   all components of the given entity
     */
    public ClassToInstanceMap<Component> getComponents(long uid) {
        return ImmutableClassToInstanceMap.copyOf(components.rowMap().get(uid));
    }
}