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/* * Copyright 2000-2013 JetBrains s.r.o. * * Licensed 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 com.jetbrains.pluginUtils.xml; import org.apache.commons.io.IOUtils; import org.jdom.*; import org.jetbrains.annotations.NonNls; import org.jetbrains.annotations.NotNull; import org.jetbrains.annotations.Nullable; import java.io.IOException; import java.net.MalformedURLException; import java.net.URL; import java.util.*; import java.util.regex.Matcher; import java.util.regex.Pattern; public class JDOMXIncluder { @NonNls private static final String HTTP_WWW_W3_ORG_2001_XINCLUDE = "http://www.w3.org/2001/XInclude"; @NonNls private static final String XI = "xi"; @NonNls private static final String INCLUDE = "include"; @NonNls private static final String HREF = "href"; @NonNls private static final String BASE = "base"; @NonNls private static final String PARSE = "parse"; @NonNls private static final String TEXT = "text"; @NonNls private static final String XML = "xml"; @NonNls private static final String ENCODING = "encoding"; @NonNls private static final String XPOINTER = "xpointer"; public static final Namespace XINCLUDE_NAMESPACE = Namespace.getNamespace(XI, HTTP_WWW_W3_ORG_2001_XINCLUDE); private JDOMXIncluder() { } public static Document resolve(@NotNull Document original, @Nullable String base) throws XIncludeException { Document result = (Document) original.clone(); Element root = result.getRootElement(); List<Content> resolved = resolve(root, base); // check that the list returned contains // exactly one root element Element newRoot = null; Iterator<Content> iterator = resolved.iterator(); while (iterator.hasNext()) { Content o = iterator.next(); if (o instanceof Element) { if (newRoot != null) { throw new XIncludeException("Tried to include multiple roots"); } newRoot = (Element) o; } else if (o instanceof Comment || o instanceof ProcessingInstruction) { // do nothing } else if (o instanceof Text) { throw new XIncludeException("Tried to include text node outside of root element"); } else if (o instanceof EntityRef) { throw new XIncludeException("Tried to include a general entity reference outside of root element"); } else { throw new XIncludeException("Unexpected type " + o.getClass()); } } if (newRoot == null) { throw new XIncludeException("No root element"); } // Could probably combine two loops List<Content> newContent = result.getContent(); // resolved contains list of new content // use it to replace old root element iterator = resolved.iterator(); // put in nodes before root element int rootPosition = newContent.indexOf(result.getRootElement()); while (iterator.hasNext()) { Content o = iterator.next(); if (o instanceof Comment || o instanceof ProcessingInstruction) { newContent.add(rootPosition, o); rootPosition++; } else if (o instanceof Element) { // the root break; } else { // throw exception???? } } // put in root element result.setRootElement(newRoot); int addPosition = rootPosition + 1; // put in nodes after root element while (iterator.hasNext()) { Content o = iterator.next(); if (o instanceof Comment || o instanceof ProcessingInstruction) { newContent.add(addPosition, o); addPosition++; } else { // throw exception???? } } return result; } public static List<Content> resolve(@NotNull Element original, @Nullable String base) throws XIncludeException { Stack<String> bases = new Stack<String>(); if (base != null) bases.push(base); List<Content> result = resolve(original, bases); bases.pop(); return result; } private static boolean isIncludeElement(Element element) { if (element.getName().equals(INCLUDE) && element.getNamespace().equals(XINCLUDE_NAMESPACE)) { return true; } return false; } protected static List<Content> resolve(Element original, Stack<String> bases) throws XIncludeException { if (!bases.isEmpty()) bases.peek(); if (isIncludeElement(original)) { return resolveXIncludeElement(original, bases); } else { Element resolvedElement = resolveNonXIncludeElement(original, bases); List<Content> resultList = new ArrayList<Content>(1); resultList.add(resolvedElement); return resultList; } } private static List<Content> resolveXIncludeElement(Element element, Stack<String> bases) throws XIncludeException { String base = ""; if (!bases.isEmpty()) base = bases.peek(); // These lines are probably unnecessary assert isIncludeElement(element); String href = element.getAttributeValue(HREF); assert href != null : "Missing href attribute"; Attribute baseAttribute = element.getAttribute(BASE, Namespace.XML_NAMESPACE); if (baseAttribute != null) { base = baseAttribute.getValue(); } URL remote; if (base != null) { try { URL context = new URL(base); remote = new URL(context, href); } catch (MalformedURLException ex) { throw new XIncludeException(ex); } } else { // base == null try { remote = new URL(href); } catch (MalformedURLException ex) { throw new XIncludeException(ex); } } boolean parse = true; final String parseAttribute = element.getAttributeValue(PARSE); if (parseAttribute != null) { if (parseAttribute.equals(TEXT)) { parse = false; } assert parseAttribute.equals(XML) : parseAttribute + "is not a legal value for the parse attribute"; } if (parse) { assert !bases.contains(remote.toExternalForm()) : "Circular XInclude Reference to " + remote.toExternalForm(); final Element fallbackElement = element.getChild("fallback", element.getNamespace()); List<Content> remoteParsed = parseRemote(bases, remote, fallbackElement); if (!remoteParsed.isEmpty()) { remoteParsed = extractNeededChildren(element, remoteParsed); } for (int i = 0; i < remoteParsed.size(); i++) { Object o = remoteParsed.get(i); if (o instanceof Element) { Element e = (Element) o; List<? extends Content> nodes = resolve(e, bases); remoteParsed.addAll(i, nodes); i += nodes.size(); remoteParsed.remove(i); i--; e.detach(); } } for (Object o : remoteParsed) { if (o instanceof Content) { Content content = (Content) o; content.detach(); } } return remoteParsed; } else { try { String encoding = element.getAttributeValue(ENCODING); String s = IOUtils.toString(remote, encoding); List<Content> resultList = new ArrayList<Content>(1); resultList.add(new Text(s)); return resultList; } catch (IOException e) { throw new XIncludeException(e); } } } //xpointer($1) @NonNls public static Pattern XPOINTER_PATTERN = Pattern.compile("xpointer\\((.*)\\)"); // /$1(/$2)?/* public static Pattern CHILDREN_PATTERN = Pattern.compile("/([^/]*)(/[^/]*)?/\\*"); @Nullable private static List<Content> extractNeededChildren(final Element element, List<Content> remoteElements) { final String xpointer = element.getAttributeValue(XPOINTER); if (xpointer != null) { Matcher matcher = XPOINTER_PATTERN.matcher(xpointer); boolean b = matcher.matches(); assert b : "Unsupported XPointer: " + xpointer; String pointer = matcher.group(1); matcher = CHILDREN_PATTERN.matcher(pointer); b = matcher.matches(); assert b : "Unsupported pointer: " + pointer; final String rootTagName = matcher.group(1); assert remoteElements.size() == 1; assert remoteElements.get(0) instanceof Element; Element e = (Element) remoteElements.get(0); if (e.getName().equals(rootTagName)) { String subTagName = matcher.group(2); if (subTagName != null) { e = e.getChild(subTagName.substring(1)); // cut off the slash } return new ArrayList<Content>(e.getContent()); } else return Collections.emptyList(); } else { return remoteElements; } } @NotNull private static List<Content> parseRemote(final Stack<String> bases, final URL remote, @Nullable Element fallbackElement) { try { Document doc = JDOMUtil.loadResourceDocument(remote); bases.push(remote.toExternalForm()); Element root = doc.getRootElement(); final List<Content> list = resolve(root, bases); bases.pop(); return list; } catch (JDOMException e) { throw new XIncludeException(e); } catch (IOException e) { if (fallbackElement != null) { // TODO[yole] return contents of fallback element (we don't have fallback elements with content ATM) return Collections.emptyList(); } throw new XIncludeException(e); } } private static Element resolveNonXIncludeElement(Element original, Stack<String> bases) throws XIncludeException { if (!bases.isEmpty()) bases.peek(); Element result = new Element(original.getName(), original.getNamespace()); Iterator<Attribute> attributes = original.getAttributes().iterator(); while (attributes.hasNext()) { Attribute a = attributes.next(); result.setAttribute((Attribute) a.clone()); } for (Content o : (List<Content>) original.getContent()) { if (o instanceof Element) { Element element = (Element) o; if (isIncludeElement(element)) { result.addContent(resolveXIncludeElement(element, bases)); } else { result.addContent(resolveNonXIncludeElement(element, bases)); } } else { result.addContent((Content) o.clone()); } } // end while return result; } }