001 /*
002 * Copyright (C) 2010 eXo Platform SAS.
003 *
004 * This is free software; you can redistribute it and/or modify it
005 * under the terms of the GNU Lesser General Public License as
006 * published by the Free Software Foundation; either version 2.1 of
007 * the License, or (at your option) any later version.
008 *
009 * This software is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * You should have received a copy of the GNU Lesser General Public
015 * License along with this software; if not, write to the Free
016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018 */
019
020 package org.crsh.vfs.spi.servlet;
021
022 import org.crsh.vfs.spi.AbstractFSDriver;
023
024 import javax.servlet.ServletContext;
025 import java.io.File;
026 import java.io.FileInputStream;
027 import java.io.IOException;
028 import java.io.InputStream;
029 import java.net.URL;
030 import java.util.Collections;
031 import java.util.Set;
032 import java.util.regex.Matcher;
033 import java.util.regex.Pattern;
034
035 /**
036 * @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a>
037 * @version $Revision$
038 */
039 public class ServletContextDriver extends AbstractFSDriver<String> {
040
041 /** A valid path. */
042 static final Pattern pathPattern = Pattern.compile("^(?=/).*?((?<=/)[^/]*)?(/?)$");
043
044 /** . */
045 private final ServletContext ctx;
046
047 public ServletContextDriver(ServletContext ctx) {
048 if (ctx == null) {
049 throw new NullPointerException();
050 }
051
052 //
053 this.ctx = ctx;
054 }
055
056 public String root() throws IOException {
057 return "/";
058 }
059
060 public String name(String file) throws IOException {
061 return matcher(file).group(1);
062 }
063
064 public boolean isDir(String file) throws IOException {
065 Matcher matcher = matcher(file);
066 String slash = matcher.group(2);
067 return "/".equals(slash);
068 }
069
070 public Iterable<String> children(String parent) throws IOException {
071 @SuppressWarnings("unchecked")
072 Set<String> resourcePaths = (Set<String>)ctx.getResourcePaths(parent);
073 return resourcePaths != null ? resourcePaths : Collections.<String>emptyList();
074 }
075
076 /**
077 * The implementation attempts to get an URL that will be valid for the file system first (when the
078 * war is usually exploded) and if it is not able, it will delegate to {@link ServletContext#getResource(String)}.
079 *
080 * @param file the file path
081 * @return the URL
082 * @throws IOException any io exception
083 */
084 public URL toURL(String file) throws IOException {
085 String realPath = ctx.getRealPath(file);
086 if (realPath != null) {
087 File realFile = new File(realPath);
088 if (realFile.exists() && realFile.isFile()) {
089 return realFile.toURI().toURL();
090 }
091 }
092 return ctx.getResource(file);
093 }
094
095 public long getLastModified(String handle) throws IOException {
096 String realPath = ctx.getRealPath(handle);
097 if (realPath != null) {
098 File realFile = new File(realPath);
099 if (realFile.exists() && realFile.isFile()) {
100 return realFile.lastModified();
101 }
102 }
103 return ctx.getResource(handle).openConnection().getLastModified();
104 }
105
106 public InputStream open(String handle) throws IOException {
107 String realPath = ctx.getRealPath(handle);
108 if (realPath != null) {
109 File realFile = new File(realPath);
110 if (realFile.exists() && realFile.isFile()) {
111 return new FileInputStream(realFile);
112 }
113 }
114 return ctx.getResource(handle).openConnection().getInputStream();
115 }
116
117 private Matcher matcher(String path) {
118 Matcher m = pathPattern.matcher(path);
119 if (m.matches()) {
120 return m;
121 } else {
122 throw new IllegalArgumentException("Illegal path " + path);
123 }
124 }
125 }