Java tutorial
/* * See the NOTICE file distributed with this work for additional * information regarding copyright ownership. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.xwiki.webjars.internal; import java.io.BufferedReader; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.net.JarURLConnection; import java.net.URI; import java.net.URISyntaxException; import java.net.URL; import java.util.Enumeration; import java.util.jar.JarEntry; import java.util.jar.JarFile; import java.util.regex.Matcher; import java.util.regex.Pattern; import org.apache.commons.io.IOUtils; import org.apache.commons.lang3.StringUtils; import org.xwiki.url.filesystem.FilesystemExportContext; /** * Saves WebJar resources to the file system. * * @version $Id: 9b24e7d077009f8442b945c87009f2e796fed863 $ * @since 9.6RC1 */ public class FilesystemResourceReferenceCopier { private static final Pattern URL_PATTERN = Pattern.compile("url\\('(.*?)'|\"(.*?)\"\\)"); private static final String CONCAT_PATH_FORMAT = "%s/%s"; private File getJARFile(String resourceName) throws IOException { // Get the JAR URL by looking up the passed resource name to extract the location of the JAR URL resourceURL = Thread.currentThread().getContextClassLoader().getResource(resourceName); JarURLConnection connection = (JarURLConnection) resourceURL.openConnection(); URL jarURL = connection.getJarFileURL(); File file; try { file = new File(jarURL.toURI()); } catch (URISyntaxException e) { file = new File(jarURL.getPath()); } return file; } void copyResourceFromJAR(String resourcePrefix, String resourceName, String targetPrefix, FilesystemExportContext exportContext) throws IOException { // Note that we cannot use ClassLoader.getResource() to access the resource since the resourcePath may point // to a directory inside the JAR, and in this case we need to copy all resources inside that directory in the // JAR! String resourcePath = String.format(CONCAT_PATH_FORMAT, resourcePrefix, resourceName); JarFile jar = new JarFile(getJARFile(resourcePath)); try { for (Enumeration<JarEntry> enumeration = jar.entries(); enumeration.hasMoreElements();) { JarEntry entry = enumeration.nextElement(); if (entry.getName().startsWith(resourcePath) && !entry.isDirectory()) { // Copy the resource! // TODO: Won't this cause collisions if the same resource is available on several subwikis // for example? String targetPath = targetPrefix + entry.getName().substring(resourcePrefix.length()); File targetLocation = new File(exportContext.getExportDir(), targetPath); if (!targetLocation.exists()) { targetLocation.getParentFile().mkdirs(); FileOutputStream fos = new FileOutputStream(targetLocation); InputStream is = jar.getInputStream(entry); IOUtils.copy(is, fos); fos.close(); is.close(); } } } } finally { jar.close(); } } void processCSS(String resourcePrefix, String resourceName, String targetPrefix, FilesystemExportContext exportContext) throws Exception { String resourcePath = String.format(CONCAT_PATH_FORMAT, resourcePrefix, resourceName); JarFile jar = new JarFile(getJARFile(resourcePath)); try { for (Enumeration<JarEntry> enumeration = jar.entries(); enumeration.hasMoreElements();) { JarEntry entry = enumeration.nextElement(); if (entry.getName().equals(resourcePath)) { // Read the CSS and look for url() entries... processCSSfile(resourcePrefix, targetPrefix, entry, jar, exportContext); break; } } } finally { jar.close(); } } private void processCSSfile(String resourcePrefix, String targetPrefix, JarEntry entry, JarFile jar, FilesystemExportContext exportContext) throws Exception { // Limitation: we only support url() constructs located on a single line try (BufferedReader br = new BufferedReader(new InputStreamReader(jar.getInputStream(entry), "UTF-8"))) { String line; while ((line = br.readLine()) != null) { Matcher matcher = URL_PATTERN.matcher(line); while (matcher.find()) { String url = matcher.group(1); // Determine if URL is relative if (isRelativeURL(url)) { // Remove any query string part and any fragment part too url = StringUtils.substringBefore(url, "?"); url = StringUtils.substringBefore(url, "#"); // Normalize paths String resourceName = String.format(CONCAT_PATH_FORMAT, StringUtils.substringBeforeLast(entry.getName(), "/"), url); resourceName = new URI(resourceName).normalize().getPath(); resourceName = resourceName.substring(resourcePrefix.length() + 1); // Copy to filesystem copyResourceFromJAR(resourcePrefix, resourceName, targetPrefix, exportContext); } } } } } private boolean isRelativeURL(String url) throws Exception { return !new URI(url).isAbsolute(); } }