/** Check if an URL is relative to another URL. */
public static boolean relativeURL(URL url1, URL url2) {
return ((url1.getProtocol() == null && url2.getProtocol() == null)
|| url1.getProtocol().equals(url2.getProtocol()))
&& ((url1.getAuthority() == null && url2.getAuthority() == null)
|| url1.getAuthority().equals(url2.getAuthority()))
&& ((url1.getPath() == null && url2.getPath() == null)
|| url2.getPath().startsWith(url1.getPath()));
}
/**
* Get the last modification date of a URL.
*
* @return last modified timestamp "as is"
*/
public static long getLastModified(URL url) throws IOException {
if ("file".equals(url.getProtocol())) {
// Optimize file: access. Also, this prevents throwing an exception if the file doesn't exist
// as we try to close the stream below.
return new File(URLDecoder.decode(url.getFile(), STANDARD_PARAMETER_ENCODING)).lastModified();
} else {
// Use URLConnection
final URLConnection urlConnection = url.openConnection();
if (urlConnection instanceof HttpURLConnection)
((HttpURLConnection) urlConnection).setRequestMethod("HEAD");
try {
return getLastModified(urlConnection);
} finally {
final InputStream is = urlConnection.getInputStream();
if (is != null) is.close();
}
}
}