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PlotSquared, a land and world management plugin for Minecraft.
There is a newer version: 6.11.2
/*
 *       _____  _       _    _____                                _
 *      |  __ \| |     | |  / ____|                              | |
 *      | |__) | | ___ | |_| (___   __ _ _   _  __ _ _ __ ___  __| |
 *      |  ___/| |/ _ \| __|\___ \ / _` | | | |/ _` | '__/ _ \/ _` |
 *      | |    | | (_) | |_ ____) | (_| | |_| | (_| | | |  __/ (_| |
 *      |_|    |_|\___/ \__|_____/ \__, |\__,_|\__,_|_|  \___|\__,_|
 *                                    | |
 *                                    |_|
 *            PlotSquared plot management system for Minecraft
 *               Copyright (C) 2014 - 2022 IntellectualSites
 *
 *     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 .
 */
package com.plotsquared.core.util;

import com.sk89q.worldedit.internal.expression.Expression;
import org.checkerframework.checker.nullness.qual.NonNull;

/**
 * An expression that can be evaluated.
 * Evaluation is thread-safe.
 * This is a wrapper for {@link Expression}.
 */
public class PlotExpression {

    private final Expression expression;
    private final Object lock = new Object();

    private PlotExpression(final @NonNull String rawExpression, final @NonNull String @NonNull [] variableNames) {
        this.expression = Expression.compile(rawExpression, variableNames);
    }

    /**
     * Compiles an expression from a string.
     *
     * @param expression    the expression to compile.
     * @param variableNames the variables that can be set in {@link #evaluate(double...)}.
     * @return the compiled expression.
     */
    public static @NonNull PlotExpression compile(
            final @NonNull String expression,
            final @NonNull String @NonNull ... variableNames
    ) {
        return new PlotExpression(expression, variableNames);
    }

    /**
     * Evaluates the expression with the given variable values.
     *
     * @param values the values to set the variables to.
     * @return the result of the evaluation.
     */
    public double evaluate(double... values) {
        double evaluate;
        // synchronization is likely the best option in terms of memory and cpu consumption
        synchronized (this.lock) {
            evaluate = this.expression.evaluate(values);
        }
        return evaluate;
    }

}