presto-accumulo/src/main/java/io/prestosql/plugin/accumulo/serializers/MapLexicoder.java/MapLexicoder/decode
class MapLexicoder:    @Override
    public Map<K, V> decode(byte[] b)
    {
        byte[][] escapedElements = split(b);
        Map<K, V> decodedMap = new HashMap<>();
        for (int i = 0; i < escapedElements.length; i += 2) {
            K key = keyLexicoder.decode(unescape(escapedElements[i]));
            V value = valueLexicoder.decode(unescape(escapedElements[i + 1]));
            decodedMap.put(key, value);
        }

        return decodedMap;
    }