Custom neo4j function not giving me proper linkedHashmap data in order

Neo4j Graph Platform Procedures & APOC
,
1

I have developed a custom function which takes Map<String, Object> and List which maintain the order which is applied on map of keys

Map<String, Object> sortedMap = new LinkedHashMap<>();
for (Map<String, Object> map : maps) {
            for (String key : keySequence) {
                if (map.containsKey(key)) {
                    sortedMap.put(key, map.get(key));
                }
            }
            System.out.println(sortedMap);
    return sortedMap;

this is my java code and built a jar and deployed that into the plugins folder and able to call successfully but when I check this code which is working fine even print statement gives me proper result but when I check the output in neo4j browser or calling neo4j function using cypher through code getting different order.

WITH ['A', 'C', 'F', 'D', 'E', 'B'] AS keySequence, 
  {D: 1, A: 2, E: 3, B: 4, C: 5, F: 6}
   AS mapData RETURN sortedkeys(mapData ,keySequence)

expected output - {A=2, C=5, F=6, D=1, E=3, B=4}
Output in neo4j Browser = {
"A": 2,
"B": 4,
"C": 5,
"D": 1,
"E": 3,
"F": 6
}

  • neo4j version; 5.1.0
  • java version: 11
  • debug log --{A=2, C=5, F=6, D=1, E=3, B=4}

appreciate the time and efforts of the member in advance who want to help me.

2

The linked hash map has a linked list backing it that saves the order of the items put into the map. This information is not being passed by the driver to the client. I imaging your map is getting serialized into a json object of key/value pairs and on the other end being deserialized into map (looks like a treeMap since it is sorted). This process loses your original map's ordering.

3

@glilienfield Thank you for the response, what will be the solution.