TrieEntry floorEntry()

in src/main/java/org/apache/commons/collections4/trie/AbstractPatriciaTrie.java [1463:1503]

33 lines of code
8 McCabe index (conditional complexity)


    TrieEntry<K, V> floorEntry(final K key) {
        // TODO: Cleanup so that we don't actually have to add/remove from the
        //       tree.  (We do it here because there are other well-defined
        //       functions to perform the search.)
        final int lengthInBits = lengthInBits(key);

        if (lengthInBits == 0) {
            if (!root.isEmpty()) {
                return root;
            }
            return null;
        }

        final TrieEntry<K, V> found = getNearestEntryForKey(key, lengthInBits);
        if (compareKeys(key, found.key)) {
            return found;
        }

        final int bitIndex = bitIndex(key, found.key);
        if (KeyAnalyzer.isValidBitIndex(bitIndex)) {
            final TrieEntry<K, V> added = new TrieEntry<>(key, null, bitIndex);
            addEntry(added, lengthInBits);
            incrementSize(); // must increment because remove will decrement
            final TrieEntry<K, V> floor = previousEntry(added);
            removeEntry(added);
            modCount -= 2; // we didn't really modify it.
            return floor;
        }
        if (KeyAnalyzer.isNullBitKey(bitIndex)) {
            if (!root.isEmpty()) {
                return root;
            }
            return null;
        }
        if (KeyAnalyzer.isEqualBitKey(bitIndex)) {
            return found;
        }

        // we should have exited above.
        throw new IllegalStateException("invalid lookup: " + key);
    }