for (final VFile file : ResourceUtil.getFilesByExtension(vfs, sourceType)) {
final VFile target = vfs.find(FilenameUtils.removeExtension(file
.getPath()) + "." + resultType);
// ... call <processorCallback>
VFSUtils.pipe(file, target, new Pipe() {
@Override
public void exec(final Reader reader, final Writer writer)
throws IOException {
callback.call(reader, writer);
}