@SuppressWarnings("squid:S1244")
private static String selectBestEncoding(String acceptEncodingHeader) {
// multiple encodings are accepted; determine best one
Collection<String> bestEncodings = new HashSet<>(3);
double bestQ = 0.0;
Collection<String> unacceptableEncodings = new HashSet<>(3);
boolean willAcceptAnything = false;
for (String token : COMMA.split(acceptEncodingHeader)) {
ContentEncodingQ contentEncodingQ = parseContentEncodingQ(token);
String contentEncoding = contentEncodingQ.getContentEncoding();
double q = contentEncodingQ.getQ();
if (ANY_ENCODING.equals(contentEncoding)) {
willAcceptAnything = q > 0.0;
} else if (SUPPORTED_ENCODINGS.contains(contentEncoding)) {
if (q > 0.0) {
// This is a header quality comparison.
// So it is safe to suppress warning squid:S1244
if (q == bestQ) {
bestEncodings.add(contentEncoding);
} else if (q > bestQ) {
bestQ = q;
bestEncodings.clear();
bestEncodings.add(contentEncoding);
}
} else {
unacceptableEncodings.add(contentEncoding);
}
}
}
if (bestEncodings.isEmpty()) {
// nothing was acceptable to us
if (willAcceptAnything) {
if (unacceptableEncodings.isEmpty()) {
return SUPPORTED_ENCODINGS.get(0);
} else {
for (String encoding : SUPPORTED_ENCODINGS) {
if (!unacceptableEncodings.contains(encoding)) {
return encoding;
}
}
}
}
} else {
for (String encoding : SUPPORTED_ENCODINGS) {
if (bestEncodings.contains(encoding)) {
return encoding;
}
}
}
return NO_ENCODING;
}
private static String parseBestEncoding(String acceptEncodingHeader) {
ContentEncodingQ contentEncodingQ = parseContentEncodingQ(acceptEncodingHeader);
String contentEncoding = contentEncodingQ.getContentEncoding();
if (contentEncodingQ.getQ() > 0.0) {
if (ANY_ENCODING.equals(contentEncoding)) {
return SUPPORTED_ENCODINGS.get(0);
} else if (SUPPORTED_ENCODINGS.contains(contentEncoding)) {
return contentEncoding;
}
}
return NO_ENCODING;
}