# NotEvaluator.java

    /*
     *  Licensed to the Apache Software Foundation (ASF) under one
     *  or more contributor license agreements.  See the NOTICE file
     *  distributed with this work for additional information
     *  regarding copyright ownership.  The ASF licenses this file
     *  to you under the Apache License, Version 2.0 (the
     *  "License"); you may not use this file except in compliance
     *  with the License.  You may obtain a copy of the License at
     *
     *   http://www.apache.org/licenses/LICENSE-2.0
     *
     *  Unless required by applicable law or agreed to in writing,
     *  software distributed under the License is distributed on an
     *   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
     *  KIND, either express or implied.  See the License for the
     *  specific language governing permissions and limitations
     *  under the License.
     */

    package org.apache.synapse.commons.evaluators;

    /**
     * This encapsulates a boolean expression. This acts as not boolean operator.
     * It executes the boolean expression inside and return the NOT of this expression.</p>
     *
     * <pre>
     * &lt;not&gt;
     *     one evaluator
     * &lt;/not&gt;
     * </pre>
     */
    public class NotEvaluator implements Evaluator {
        private Evaluator evaluator;

        public boolean evaluate(EvaluatorContext context) throws EvaluatorException {
            return !evaluator.evaluate(context);
        }

        public String getName() {
            return EvaluatorConstants.NOT;
        }

        public void setEvaluator(Evaluator evaluator) {
            this.evaluator = evaluator;
        }

        public Evaluator getEvaluator() {
            return evaluator;
        }
    }