001package org.apache.commons.digester3.plugins;
002
003/*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements.  See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership.  The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License.  You may obtain a copy of the License at
011 *
012 *   http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied.  See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022import org.apache.commons.digester3.Digester;
023
024/**
025 * Interface for classes which can dynamically load custom plugin rules associated with a user's plugin class.
026 * <p>
027 * Each plugin declaration has an associated RuleLoader instance, and that instance's addRules method is invoked each
028 * time the input xml specifies that an instance of that plugged-in class is to be created.
029 * <p>
030 * This is an abstract class rather than an interface in order to make it possible to enhance this class in future
031 * without breaking binary compatibility; it is possible to add methods to an abstract class, but not to an interface.
032 * 
033 * @since 1.6
034 */
035public abstract class RuleLoader
036{
037
038    /**
039     * Configures the digester with custom rules for some plugged-in class.
040     * <p>
041     * This method is invoked when the start of an xml tag is encountered which maps to a PluginCreateRule. Any rules
042     * added here are removed from the digester when the end of that xml tag is encountered.
043     *
044     * @param d The gigester has to be configured
045     * @param path The path where rule has to be bound
046     * @throws PluginException if any error occurs
047     */
048    public abstract void addRules( Digester d, String path )
049        throws PluginException;
050
051}