code: protected Set<Resource> doFindMatchingFileSystemResources(File rootDir, String subPattern) throws IOException {
  		if (logger.isDebugEnabled()) {
  			logger.debug("Looking for matching resources in directory tree [" + rootDir.getPath() + "]");
  		}
  		Set<File> matchingFiles = retrieveMatchingFiles(rootDir, subPattern);
  		Set<Resource> result = new LinkedHashSet<Resource>(matchingFiles.size());
  		for (File file : matchingFiles) {
  			result.add(new FileSystemResource(file));
  		}
  		return result;
  	}
docs: 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 a mutable Set of matching Resource instances
  @throws IOException in case of I/O errors
  @see #retrieveMatchingFiles