pathmatchingresourcepatternresolver.java

spring api 源代码

	protected Resource[] findAllClassPathResources(String location) throws IOException {
		String path = location;
		if (path.startsWith("/")) {
			path = path.substring(1);
		}
		Enumeration resourceUrls = getClassLoader().getResources(path);
		Set result = CollectionFactory.createLinkedSetIfPossible(16);
		while (resourceUrls.hasMoreElements()) {
			URL url = (URL) resourceUrls.nextElement();
			result.add(convertClassLoaderURL(url));
		}
		return (Resource[]) result.toArray(new Resource[result.size()]);
	}

	/**
	 * Convert the given URL as returned from the ClassLoader into a Resource object.
	 * <p>The default implementation simply creates a UrlResource instance.
	 * @param url a URL as returned from the ClassLoader
	 * @return the corresponding Resource object
	 * @see java.lang.ClassLoader#getResources
	 * @see org.springframework.core.io.Resource
	 */
	protected Resource convertClassLoaderURL(URL url) {
		return new UrlResource(url);
	}

	/**
	 * Find all resources that match the given location pattern via the
	 * Ant-style PathMatcher. Supports resources in jar files and zip files
	 * and in the file system.
	 * @param locationPattern the location pattern to match
	 * @return the result as Resource array
	 * @throws IOException in case of I/O errors
	 * @see #doFindPathMatchingJarResources
	 * @see #doFindPathMatchingFileResources
	 * @see org.springframework.util.PathMatcher
	 */
	protected Resource[] findPathMatchingResources(String locationPattern) throws IOException {
		String rootDirPath = determineRootDir(locationPattern);
		String subPattern = locationPattern.substring(rootDirPath.length());
		Resource[] rootDirResources = getResources(rootDirPath);
		Set result = CollectionFactory.createLinkedSetIfPossible(16);
		for (int i = 0; i < rootDirResources.length; i++) {
			Resource rootDirResource = rootDirResources[i];
			if (isJarResource(rootDirResource)) {
				result.addAll(doFindPathMatchingJarResources(rootDirResource, subPattern));
			}
			else {
				result.addAll(doFindPathMatchingFileResources(rootDirResource, subPattern));
			}
		}
		if (logger.isDebugEnabled()) {
			logger.debug("Resolved location pattern [" + locationPattern + "] to resources " + result);
		}
		return (Resource[]) result.toArray(new Resource[result.size()]);
	}

	/**
	 * Determine the root directory for the given location.
	 * <p>Used for determining the starting point for file matching,
	 * resolving the root directory location to a <code>java.io.File</code>
	 * and passing it into <code>retrieveMatchingFiles</code>, with the
	 * remainder of the location as pattern.
	 * <p>Will return "/WEB-INF" for the pattern "/WEB-INF/*.xml",
	 * for example.
	 * @param location the location to check
	 * @return the part of the location that denotes the root directory
	 * @see #retrieveMatchingFiles
	 */
	protected String determineRootDir(String location) {
		int prefixEnd = location.indexOf(":") + 1;
		int rootDirEnd = location.length();
		while (rootDirEnd > prefixEnd && getPathMatcher().isPattern(location.substring(prefixEnd, rootDirEnd))) {
			rootDirEnd = location.lastIndexOf('/', rootDirEnd - 2) + 1;
		}
		if (rootDirEnd == 0) {
			rootDirEnd = prefixEnd;
		}
		return location.substring(0, rootDirEnd);
	}

	/**
	 * Return whether the given resource handle indicates a jar resource
	 * that the <code>doFindPathMatchingJarResources</code> method can handle.
	 * <p>The default implementation checks against the URL protocols
	 * "jar", "zip" and "wsjar" (the latter are used by BEA WebLogic Server
	 * and IBM WebSphere, respectively, but can be treated like jar files).
	 * @param resource the resource handle to check
	 * (usually the root directory to start path matching from)
	 * @see #doFindPathMatchingJarResources
	 * @see org.springframework.util.ResourceUtils#isJarURL
	 */
	protected boolean isJarResource(Resource resource) throws IOException {
		return ResourceUtils.isJarURL(resource.getURL());
	}

	/**
	 * Find all resources in jar files that match the given location pattern
	 * via the Ant-style PathMatcher.
	 * @param rootDirResource the root directory as Resource
	 * @param subPattern the sub pattern to match (below the root directory)
	 * @return the Set of matching Resource instances
	 * @throws IOException in case of I/O errors
	 * @see java.net.JarURLConnection
	 * @see org.springframework.util.PathMatcher
	 */
	protected Set doFindPathMatchingJarResources(Resource rootDirResource, String subPattern) throws IOException {
		URLConnection con = rootDirResource.getURL().openConnection();
		JarFile jarFile = null;
		boolean newJarFile = false;
		String jarFileUrl = null;
		String rootEntryPath = null;

		if (con instanceof JarURLConnection) {
			// Should usually be the case for traditional JAR files.
			JarURLConnection jarCon = (JarURLConnection) con;
			jarFile = jarCon.getJarFile();
			jarFileUrl = jarCon.getJarFileURL().toExternalForm();
			JarEntry jarEntry = jarCon.getJarEntry();
			rootEntryPath = (jarEntry != null ? jarEntry.getName() : "");
		}
		else {
			// No JarURLConnection -> need to resort to URL file parsing.
			// We'll assume URLs of the format "jar:path!/entry", with the protocol
			// being arbitrary as long as following the entry format.
			// We'll also handle paths with and without leading "file:" prefix.
			String urlFile = rootDirResource.getURL().getFile();
			int separatorIndex = urlFile.indexOf(ResourceUtils.JAR_URL_SEPARATOR);
			jarFileUrl = urlFile.substring(0, separatorIndex);
			if (jarFileUrl.startsWith(ResourceUtils.FILE_URL_PREFIX)) {
				jarFileUrl = jarFileUrl.substring(ResourceUtils.FILE_URL_PREFIX.length());
			}
			jarFile = new JarFile(jarFileUrl);
			newJarFile = true;
			jarFileUrl = ResourceUtils.FILE_URL_PREFIX + jarFileUrl;
			rootEntryPath = urlFile.substring(separatorIndex + ResourceUtils.JAR_URL_SEPARATOR.length());
		}

		try {
			if (logger.isDebugEnabled()) {
				logger.debug("Looking for matching resources in jar file [" + jarFileUrl + "]");
			}
			if (!"".equals(rootEntryPath) && !rootEntryPath.endsWith("/")) {
				// Root entry path must end with slash to allow for proper matching.
				// The Sun JRE does not return a slash here, but BEA JRockit does.
				rootEntryPath = rootEntryPath + "/";
			}
			Set result = CollectionFactory.createLinkedSetIfPossible(8);
			for (Enumeration entries = jarFile.entries(); entries.hasMoreElements();) {
				JarEntry entry = (JarEntry) entries.nextElement();
				String entryPath = entry.getName();
				if (entryPath.startsWith(rootEntryPath)) {
					String relativePath = entryPath.substring(rootEntryPath.length());
					if (getPathMatcher().match(subPattern, relativePath)) {
						result.add(rootDirResource.createRelative(relativePath));
					}
				}
			}
			return result;
		}
		finally {
			// Close jar file, but only if freshly obtained -
			// not from JarURLConnection, which might cache the file reference.
			if (newJarFile) {
				jarFile.close();
			}
		}
	}

	/**
	 * Find all resources in the file system that match the given location pattern
	 * via the Ant-style PathMatcher.
	 * @param rootDirResource the root directory as Resource
	 * @param subPattern the sub pattern to match (below the root directory)
	 * @return the Set of matching Resource instances
	 * @throws IOException in case of I/O errors
	 * @see #retrieveMatchingFiles
	 * @see org.springframework.util.PathMatcher
	 */
	protected Set doFindPathMatchingFileResources(Resource rootDirResource, String subPattern) throws IOException {
		File rootDir = null;
		try {
			rootDir = rootDirResource.getFile().getAbsoluteFile();
		}
		catch (IOException ex) {
			if (logger.isDebugEnabled()) {
				logger.debug("Cannot search for matching files underneath " + rootDirResource +
						" because it does not correspond to a directory in the file system", ex);
			}
			return Collections.EMPTY_SET;
		}
		return doFindMatchingFileSystemResources(rootDir, subPattern);
	}

	/**
	 * Find all resources in the file system that match the given location pattern
	 * via the Ant-style PathMatcher.
	 * @param rootDir the root directory in the file system
	 * @param subPattern the sub pattern to match (below the root directory)
	 * @return the Set of matching Resource instances
	 * @throws IOException in case of I/O errors
	 * @see #retrieveMatchingFiles
	 * @see org.springframework.util.PathMatcher
	 */
	protected Set doFindMatchingFileSystemResources(File rootDir, String subPattern) throws IOException {
		if (logger.isDebugEnabled()) {
			logger.debug("Looking for matching resources in directory tree [" + rootDir.getPath() + "]");
		}
		Set matchingFiles = retrieveMatchingFiles(rootDir, subPattern);
		Set result = CollectionFactory.createLinkedSetIfPossible(matchingFiles.size());
		for (Iterator it = matchingFiles.iterator(); it.hasNext();) {
			File file = (File) it.next();
			result.add(new FileSystemResource(file));
		}
		return result;
	}

	/**
	 * Retrieve files that match the given path pattern,
	 * checking the given directory and its subdirectories.
	 * @param rootDir the directory to start from
	 * @param pattern the pattern to match against,
	 * relative to the root directory
	 * @return the Set of matching File instances
	 * @throws IOException if directory contents could not be retrieved
	 */
	protected Set retrieveMatchingFiles(File rootDir, String pattern) throws IOException {
		if (!rootDir.isDirectory()) {
			throw new IllegalArgumentException("Resource path [" + rootDir + "] does not denote a directory");
		}
		String fullPattern = StringUtils.replace(rootDir.getAbsolutePath(), File.separator, "/");
		if (!pattern.startsWith("/")) {
			fullPattern += "/";
		}
		fullPattern = fullPattern + StringUtils.replace(pattern, File.separator, "/");
		Set result = CollectionFactory.createLinkedSetIfPossible(8);
		doRetrieveMatchingFiles(fullPattern, rootDir, result);
		return result;
	}

	/**
	 * Recursively retrieve files that match the given pattern,
	 * adding them to the given result list.
	 * @param fullPattern the pattern to match against,
	 * with preprended root directory path
	 * @param dir the current directory
	 * @param result the Set of matching File instances to add to
	 * @throws IOException if directory contents could not be retrieved
	 */
	protected void doRetrieveMatchingFiles(String fullPattern, File dir, Set result) throws IOException {
		if (logger.isDebugEnabled()) {
			logger.debug("Searching directory [" + dir.getAbsolutePath() +
					"] for files matching pattern [" + fullPattern + "]");
		}
		File[] dirContents = dir.listFiles();
		if (dirContents == null) {
			throw new IOException("Could not retrieve contents of directory [" + dir.getAbsolutePath() + "]");
		}
		boolean dirDepthNotFixed = (fullPattern.indexOf("**") != -1);
		for (int i = 0; i < dirContents.length; i++) {
			String currPath = StringUtils.replace(dirContents[i].getAbsolutePath(), File.separator, "/");
			if (dirContents[i].isDirectory() &&
					(dirDepthNotFixed ||
					StringUtils.countOccurrencesOf(currPath, "/") < StringUtils.countOccurrencesOf(fullPattern, "/"))) {
				doRetrieveMatchingFiles(fullPattern, dirContents[i], result);
			}
			if (getPathMatcher().match(fullPattern, currPath)) {
				result.add(dirContents[i]);
			}
		}
	}

}