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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package jdk.jfr.internal.jfc.model;

import java.util.List;

// Corresponds to <not>
final class XmlNot extends XmlExpression {

    @Override
    boolean isEntity() {
        return false;
    }

    @Override
    protected void validateChildConstraints() throws JFCModelException {
        if (getExpressions().size() != 1) {
            throw new JFCModelException("Expected <not> to have a single child");
        }
    }

    @Override
    protected Result evaluate() {
        List<XmlElement> producers = getProducers();
        if (!producers.isEmpty()) {
            Result r = producers.getFirst().evaluate();
            if (!r.isNull()) {
                return r.isTrue() ? Result.FALSE : Result.TRUE;
            }
        }
        return Result.NULL;
    }
}
