| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.sling.servlets.get.impl.util; |
| |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.LinkedList; |
| import java.util.List; |
| import java.util.Map; |
| |
| import javax.json.JsonObject; |
| import javax.json.JsonObjectBuilder; |
| |
| import org.apache.sling.api.request.RecursionTooDeepException; |
| import org.apache.sling.api.resource.Resource; |
| |
| public class ResourceTraversor |
| { |
| Map<Resource, List<Resource>> tree = new HashMap<>(); |
| |
| private long count; |
| |
| private long maxResources; |
| |
| private final int maxRecursionLevels; |
| |
| private final JsonObjectBuilder startObject; |
| |
| private LinkedList<Resource> currentQueue; |
| |
| private LinkedList<Resource> nextQueue; |
| |
| private final Resource startResource; |
| |
| private boolean ecmaSupport; |
| |
| /** Create a ResourceTraversor, optionally limiting recursion and total number of resources |
| * @param levels recursion levels limit, -1 means no limit |
| * @param maxResources maximum number of resources to collect, ignored if levels == 1 |
| * @param resource the root resource to traverse |
| * @param tidy not used |
| * @throws JSONException |
| */ |
| public ResourceTraversor(final int levels, final long maxResources, final Resource resource, boolean ecmaSupport) { |
| this.maxResources = maxResources; |
| this.maxRecursionLevels = levels; |
| this.startResource = resource; |
| currentQueue = new LinkedList<>(); |
| nextQueue = new LinkedList<>(); |
| this.ecmaSupport = ecmaSupport; |
| this.startObject = this.adapt(resource); |
| } |
| |
| /** |
| * Recursive descent from startResource, collecting JSONObjects into |
| * startObject. Throws a RecursionTooDeepException if the maximum number of |
| * nodes is reached on a "deep" traversal (where "deep" === level greater |
| * than 1). |
| * |
| * @return -1 if everything went fine, a positive value when the resource |
| * has more child nodes then allowed. |
| * @throws JSONException |
| */ |
| public int collectResources() throws RecursionTooDeepException { |
| return collectChildren(startResource, 0); |
| } |
| |
| /** |
| * @param resource |
| * @param currentLevel |
| * @throws JSONException |
| */ |
| private int collectChildren(final Resource resource, int currentLevel) { |
| |
| if (maxRecursionLevels == -1 || currentLevel < maxRecursionLevels) { |
| final Iterator<Resource> children = resource.listChildren(); |
| List<Resource> childTree = tree.get(resource); |
| if (childTree == null) |
| { |
| childTree = new ArrayList<>(); |
| tree.put(resource, childTree); |
| } |
| |
| while (children.hasNext()) { |
| count++; |
| final Resource child = children.next(); |
| // SLING-2320: always allow enumeration of one's children; |
| // DOS-limitation is for deeper traversals. |
| if (count > maxResources && maxRecursionLevels != 1) { |
| return currentLevel; |
| } |
| nextQueue.addLast(child); |
| childTree.add(child); |
| } |
| } |
| |
| // do processing only at first level to avoid unnecessary recursion |
| if (currentLevel > 0) { |
| return -1; |
| } |
| |
| while (!currentQueue.isEmpty() || !nextQueue.isEmpty()) { |
| if (currentQueue.isEmpty()) { |
| currentLevel++; |
| currentQueue = nextQueue; |
| nextQueue = new LinkedList<>(); |
| } |
| final int maxLevel = collectChildren(currentQueue.removeFirst(), currentLevel); |
| if ( maxLevel != -1 ) { |
| return maxLevel; |
| } |
| } |
| return -1; |
| } |
| |
| /** |
| * Adapt a Resource to a JSON Object. |
| * |
| * @param resource The resource to adapt. |
| * @return The JSON representation of the Resource |
| * @throws JSONException |
| */ |
| private JsonObjectBuilder adapt(final Resource resource) { |
| return new JsonObjectCreator(resource,ecmaSupport).create(); |
| } |
| |
| public JsonObject getJSONObject() { |
| return addChildren(startResource,startObject).build(); |
| } |
| |
| private JsonObjectBuilder addChildren(Resource resource,JsonObjectBuilder builder) { |
| List<Resource> children = tree.get(resource); |
| |
| if (children != null) |
| { |
| for (Resource child:children) { |
| builder.add(child.getName(), addChildren(child, adapt(child))); |
| } |
| } |
| |
| return builder; |
| } |
| } |