    001    /*
    002     * Licensed to the Apache Software Foundation (ASF) under one or more
    003     * contributor license agreements.  See the NOTICE file distributed with
    004     * this work for additional information regarding copyright ownership.
    005     * The ASF licenses this file to You under the Apache License, Version 2.0
    006     * (the "License"); you may not use this file except in compliance with
    007     * the License.  You may obtain a copy of the License at
    008     *
    009     *      http://www.apache.org/licenses/LICENSE-2.0
    010     *
    011     * Unless required by applicable law or agreed to in writing, software
    012     * distributed under the License is distributed on an "AS IS" BASIS,
    013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014     * See the License for the specific language governing permissions and
    015     * limitations under the License.
    016     */
    017    package org.apache.commons.jexl2;
    018
    019    /**
    020     * A readonly context wrapper.
    021     * @since 2.1
    022     */
    023    public final class ReadonlyContext implements JexlContext {
    024        /** The wrapped context. */
    025        private final JexlContext wrapped;
    026
    027        /**
    028         * Creates a new readonly context.
    029         * @param context the wrapped context
    030         */
    031        public ReadonlyContext(JexlContext context) {
    032            wrapped = context;
    033        }
    034
    035        /** {@inheritDoc} */
    036        public Object get(String name) {
    037            return wrapped.get(name);
    038        }
    039
    040        /**
    041         * Will throw an UnsupportedOperationException when called; the JexlEngine deals with it appropriately.
    042         * @param name the unused variable name
    043         * @param value the unused variable value
    044         */
    045        public void set(String name, Object value) {
    046            throw new UnsupportedOperationException("Not supported.");
    047        }
    048
    049        /** {@inheritDoc} */
    050        public boolean has(String name) {
    051            return wrapped.has(name);
    052        }
    053    }