Java tutorial
// ======================================================================== // $Id: FileResource.java,v 1.31 2006/01/04 13:55:31 gregwilkins Exp $ // Copyright 1996-2004 Mort Bay Consulting Pty. Ltd. // ------------------------------------------------------------------------ // 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 net.lightbody.bmp.proxy.jetty.util; import net.lightbody.bmp.proxy.jetty.log.LogFactory; import org.apache.commons.logging.Log; import java.io.*; import java.net.*; import java.net.URI; import java.security.Permission; /* ------------------------------------------------------------ */ /** File Resource. * * Handle resources of implied or explicit file type. * This class can check for aliasing in the filesystem (eg case * insensitivity). By default this is turned on if the platform does * not have the "/" path separator, or it can be controlled with the * "org.mortbay.util.FileResource.checkAliases" system parameter. * * If alias checking is turned on, then aliased resources are * treated as if they do not exist, nor can they be created. * * @version $Revision: 1.31 $ * @author Greg Wilkins (gregw) */ public class FileResource extends URLResource { private static Log log = LogFactory.getLog(Credential.class); private static boolean __checkAliases; static { __checkAliases = "true".equalsIgnoreCase( System.getProperty("net.lightbody.bmp.proxy.jetty.util.FileResource.checkAliases", "true")); if (__checkAliases) log.info("Checking Resource aliases"); } /* ------------------------------------------------------------ */ private File _file; private transient URL _alias = null; private transient boolean _aliasChecked = false; /* ------------------------------------------------------------------------------- */ /** setCheckAliases. * @param checkAliases True of resource aliases are to be checked for (eg case insensitivity or 8.3 short names) and treated as not found. */ public static void setCheckAliases(boolean checkAliases) { __checkAliases = checkAliases; } /* ------------------------------------------------------------------------------- */ /** getCheckAliases. * @return True of resource aliases are to be checked for (eg case insensitivity or 8.3 short names) and treated as not found. */ public static boolean getCheckAliases() { return __checkAliases; } /* -------------------------------------------------------- */ FileResource(URL url) throws IOException, URISyntaxException { super(url, null); try { // Try standard API to convert URL to file. _file = new File(new URI(url.toString())); } catch (Exception e) { LogSupport.ignore(log, e); try { // Assume that File.toURL produced unencoded chars. So try // encoding them. String urls = "file:" + net.lightbody.bmp.proxy.jetty.util.URI.encodePath(url.toString().substring(5)); _file = new File(new URI(urls)); } catch (Exception e2) { LogSupport.ignore(log, e2); // Still can't get the file. Doh! try good old hack! checkConnection(); Permission perm = _connection.getPermission(); _file = new File(perm == null ? url.getFile() : perm.getName()); } } if (_file.isDirectory() && !_urlString.endsWith("/")) _urlString = _urlString + "/"; } /* -------------------------------------------------------- */ FileResource(URL url, URLConnection connection, File file) { super(url, connection); _file = file; if (_file.isDirectory() && !_urlString.endsWith("/")) _urlString = _urlString + "/"; } /* -------------------------------------------------------- */ public Resource addPath(String path) throws IOException, MalformedURLException { FileResource r = null; if (!isDirectory()) { r = (FileResource) super.addPath(path); } else { path = net.lightbody.bmp.proxy.jetty.util.URI.canonicalPath(path); // treat all paths being added as relative String rel = path; if (path.startsWith("/")) rel = path.substring(1); File newFile = new File(_file, rel.replace('/', File.separatorChar)); r = new FileResource(newFile.toURI().toURL(), null, newFile); } String encoded = net.lightbody.bmp.proxy.jetty.util.URI.encodePath(path); int expected = r._urlString.length() - encoded.length(); int index = r._urlString.lastIndexOf(encoded, expected); if (expected != index && ((expected - 1) != index || path.endsWith("/") || !r.isDirectory())) { r._alias = r._url; r._aliasChecked = true; } return r; } /* ------------------------------------------------------------ */ public URL getAlias() { if (__checkAliases && !_aliasChecked) { try { String abs = _file.getAbsolutePath(); String can = _file.getCanonicalPath(); if (abs.length() != can.length() || !abs.equals(can)) _alias = new File(can).toURI().toURL(); _aliasChecked = true; if (_alias != null && log.isDebugEnabled()) { log.debug("ALIAS abs=" + abs); log.debug("ALIAS can=" + can); } } catch (Exception e) { log.warn(LogSupport.EXCEPTION, e); return getURL(); } } return _alias; } /* -------------------------------------------------------- */ /** * Returns true if the resource exists. */ public boolean exists() { return _file.exists(); } /* -------------------------------------------------------- */ /** * Returns the last modified time */ public long lastModified() { return _file.lastModified(); } /* -------------------------------------------------------- */ /** * Returns true if the respresenetd resource is a container/directory. */ public boolean isDirectory() { return _file.isDirectory(); } /* --------------------------------------------------------- */ /** * Return the length of the resource */ public long length() { return _file.length(); } /* --------------------------------------------------------- */ /** * Returns the name of the resource */ public String getName() { return _file.getAbsolutePath(); } /* ------------------------------------------------------------ */ /** * Returns an File representing the given resource or NULL if this * is not possible. */ public File getFile() { return _file; } /* --------------------------------------------------------- */ /** * Returns an input stream to the resource */ public InputStream getInputStream() throws IOException { return new FileInputStream(_file); } /* --------------------------------------------------------- */ /** * Returns an output stream to the resource */ public OutputStream getOutputStream() throws java.io.IOException, SecurityException { return new FileOutputStream(_file); } /* --------------------------------------------------------- */ /** * Deletes the given resource */ public boolean delete() throws SecurityException { return _file.delete(); } /* --------------------------------------------------------- */ /** * Rename the given resource */ public boolean renameTo(Resource dest) throws SecurityException { if (dest instanceof FileResource) return _file.renameTo(((FileResource) dest)._file); else return false; } /* --------------------------------------------------------- */ /** * Returns a list of resources contained in the given resource */ public String[] list() { String[] list = _file.list(); if (list == null) return null; for (int i = list.length; i-- > 0;) { if (new File(_file, list[i]).isDirectory() && !list[i].endsWith("/")) list[i] += "/"; } return list; } /* ------------------------------------------------------------ */ /** Encode according to this resource type. * File URIs are encoded. * @param uri URI to encode. * @return The uri unchanged. */ public String encode(String uri) { return uri; } /* ------------------------------------------------------------ */ /** * @param o * @return */ public boolean equals(Object o) { if (this == o) return true; if (null == o || !(o instanceof FileResource)) return false; FileResource f = (FileResource) o; return f._file == _file || (null != _file && _file.equals(f._file)); } /* ------------------------------------------------------------ */ /** * @return the hashcode. */ public int hashCode() { return null == _file ? super.hashCode() : _file.hashCode(); } }