    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     *
    021     * This interface declares how to resolve a namespace from its name; it is used by the interpreter during evalutation.
    022     * <p>
    023     * In JEXL, a namespace is an object that serves the purpose of encapsulating functions; for instance,
    024     * the "math" namespace would be the proper object to expose functions like "log(...)", "sinus(...)", etc.
    025     * </p>
    026     * In expressions like "ns:function(...)", the resolver is called with resolveNamespace("ns").
    027     * <p>
    028     * JEXL itself reserves 'jexl' and 'ujexl' as namespaces for internal purpose; resolving those may lead to unexpected
    029     * results.
    030     * </p>
    031     * @since 2.1
    032     */
    033    public interface NamespaceResolver {
    034        /**
    035         * Resolves a namespace by its name.
    036         * @param name the name
    037         * @return the namespace object
    038         */
    039        Object resolveNamespace(String name);
    040    }