/*
 * Copyright (c) 2024, 2025, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package compiler.lib.generators;

import java.util.ArrayList;
import java.util.Collection;

class RandomElementGenerator<T> extends BoundGenerator<T> {
    private final ArrayList<T> elements;
    private final Generator<Integer> generator;

    RandomElementGenerator(Generators g, Collection<T> elements) {
        super(g);
        this.elements = new ArrayList<>(elements);
        if (this.elements.isEmpty()) throw new EmptyGeneratorException();
        this.generator = g.uniformInts(0, elements.size() - 1);
    }

    @Override
    public final T next() {
        return elements.get(generator.next());
    }
}