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 */
017package org.apache.commons.jexl2;
018
019/**
020 * A readonly context wrapper.
021 * @since 2.1
022 */
023public 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}