LocationRadiusFilter.java

package com.github.rmsy.litelog.impl.filter;

import com.github.rmsy.litelog.Change;
import com.github.rmsy.litelog.Filter;
import com.google.common.base.Preconditions;
import org.bukkit.Location;

import javax.annotation.Nonnull;

/**
 * Filter to target only the blocks within the specified distance of the specified location.
 */
public class LocationRadiusFilter extends Filter {
    /**
     * This filter's reference location.
     */
    @Nonnull
    private final Location location;
    /**
     * This filter's reference distance (squared).
     */
    private final double distance;

    private LocationRadiusFilter() {
        this.location = null;
        this.distance = 0.0;
    }

    /**
     * Creates a new location radius filter.
     *
     * @param location The filter's reference location.
     * @param distance The filter's reference distance; must be >= <code>1.0</code>.
     */
    public LocationRadiusFilter(@Nonnull final Location location, final double distance) {
        this.location = Preconditions.checkNotNull(location, "location");
        Preconditions.checkArgument(distance >= 1.0, "distance");
        this.distance = distance * distance;
    }

    /**
     * Checks if the specified change passes the filter.
     *
     * @param change The change to be checked.
     * @return Whether or not the specified change passes the filter.
     */
    @Override
    public boolean check(@Nonnull Change change) {
        return Preconditions.checkNotNull(change, "change").getBlock().getLocation().distanceSquared(this.location) <= this.distance;
    }
}