    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
    018package org.apache.commons.jxpath;
    019
    020/**
    021 * The {@link JXPathContext#createPath JXPathContext.createPath()} method of JXPathContext can create missing objects as it traverses an XPath; it utilizes an
    022 * AbstractFactory for that purpose. Install a factory on JXPathContext by calling {@link JXPathContext#setFactory JXPathContext. setFactory()}.
    023 * <p>
    024 * All methods of this class return false. Override any of them to return true to indicate that the factory has successfully created the described object.
    025 * </p>
    026 */
    027public abstract class AbstractFactory {
    028
    029
    030    /**
    031     * Constructs a new instance for subclasses.
    032     */
    033    public AbstractFactory() {
    034        // empty
    035    }
    036
    037    /**
    038     * The parameters may describe a collection element or an individual object. It is up to the factory to infer which one it is. If it is a collection, the
    039     * factory should check if the collection exists. If not, it should create the collection. Then it should create the index'th element of the collection and
    040     * return true.
    041     *
    042     * @param context can be used to evaluate other XPaths, get to variables etc.
    043     * @param pointer describes the location of the node to be created
    044     * @param parent  is the object that will serve as a parent of the new object
    045     * @param name    is the name of the child of the parent that needs to be created. In the case of DOM may be qualified.
    046     * @param index   is used if the pointer represents a collection element. You may need to expand or even create the collection to accommodate the new
    047     *                element.
    048     *
    049     * @return true if the object was successfully created
    050     */
    051    public boolean createObject(final JXPathContext context, final Pointer pointer, final Object parent, final String name, final int index) {
    052        return false;
    053    }
    054
    055    /**
    056     * Declare the specified variable
    057     *
    058     * @param context hosts variable pools. See {@link JXPathContext#getVariables() JXPathContext.getVariables()}
    059     * @param name    is the name of the variable without the "$" sign
    060     * @return true if the variable was successfully defined
    061     */
    062    public boolean declareVariable(final JXPathContext context, final String name) {
    063        return false;
    064    }
    065}