src/main/java/org/jivesoftware/smack/util/collections/AbstractHashedMap.java
public boolean containsKey(Object key) {
        int hashCode = hash((key == null) ? NULL : key);
        HashEntry entry = data[hashIndex(hashCode, data.length)]; // no local
                                                                  // for hash
                                                                  // index
        while (entry != null) {
            if (entry.hashCode == hashCode && isEqualKey(key, entry.getKey())) {
                return true;
            }
            entry = entry.next;
        }
        return false;
    }
public boolean containsKey(Object key) {
        int hashCode = hash((key == null) ? NULL : key);
        HashEntry entry = data[hashIndex(hashCode, data.length)]; // no local
                                                                  // for hash
                                                                  // index
        while (entry != null) {
            if (entry.hashCode == hashCode && isEqualKey(key, entry.getKey())) {
                return true;
            }
            entry = entry.next;
        }
        return false;
    }
Checks whether the map contains the specified key.

@param key
the key to search for
@return true if the map contains the key