in tiles-request-api/src/main/java/org/apache/tiles/request/collection/HeaderValuesMap.java [326:336]
private boolean containsEntry(Map.Entry<String, String[]> entry) {
Enumeration<String> entryValues = request.getValues(key(entry.getKey()));
String[] valueArray = entry.getValue();
Set<String> values = array2set(valueArray);
while (entryValues.hasMoreElements()) {
if (!values.remove(entryValues.nextElement())) {
return false;
}
}
return values.isEmpty();
}