@Override
public synchronized boolean updateIfChanged(String identifier)
throws IOException, RegistryException {
// identify installed vocabulary by identifier
Vocabulary installed = get(identifier);
if (installed != null) {
// match vocabulary by identifier and issued date
Vocabulary matched = null;
for (Vocabulary v : registryManager.getVocabularies()) {
if (v.getUriString() != null
&& v.getUriString().equalsIgnoreCase(identifier)
&& installed.getIssued() != null
&& v.getIssued() != null
&& installed.getIssued().compareTo(v.getIssued()) == 0) {
matched = v;
break;
}
}
// verify the version was updated
if (matched != null && matched.getUriResolvable() != null) {
File vocabFile = getVocabFile(matched.getUriResolvable());
return downloader.downloadIfChanged(matched.getUriResolvable().toURL(), vocabFile);
}
}
return false;
}
/**
* Download a vocabulary into temporary file and return it.
*
* @param url URL of vocabulary to download
* @return temporary file vocabulary was downloaded to, or null if it failed to be downloaded
*/
private File download(URL url) throws IOException {
Preconditions.checkNotNull(url);
String filename = url.toString().replaceAll("[/:.]+", "_") + ".xml";
File tmpFile = dataDir.tmpFile(filename);
StatusLine statusLine = downloader.download(url, tmpFile);
if (success(statusLine)) {
log.info("Successfully downloaded vocabulary: " + url.toString());
return tmpFile;
} else {
String msg =
"Failed to download vocabulary: "
+ url.toString()
+ ". Response="
+ String.valueOf(statusLine.getStatusCode());
log.error(msg);
throw new IOException(msg);
}
}