JSON structure not being recognised as JSONObject or JSONArray

I'm having difficulty in parsing my json file into something that I can work with. The json file looks like this:

{
    "characterizations_values": [
        {
            "filename": "TestDoc",
            "sheet": {
                "my-title": [
                    {
                        "number": "ddddko9",
                        "numbered-part": "test number",
                        "documents": [
                            [
                                {
                                    "document_name": "20 Minutes",
                                    "document-category": [
                                        "Accounting",
                                        "Cost-Management"
                                    ]
                                }
                            ]
                        ] 
                    }
                ],
                "my-notes": [
                    {
                        "dimensions": {
                            "enclosing": {
                                "test-one": 34.33,
                                "test-two": 34
                            },
                            "enclosing-extra": {
                                "test-one": 27.33,
                                "test-two": 88
                            }
                        }
                    }
                ]
            }
        }
    ]
}

What I've attempted with the library json-simple is the following:

import org.json.simple.JSONObject;
import org.json.simple.JSONArray;

                Map<String, String> curValues = (Map<String,String>) curBlock.get("characterizations_values");
                
                // break down sheet
                JSONObject sheet = new JSONObject();
                sheet.put("sheet", curValues.get("sheet"));
                LOG.info(String.format("sheet: %s", sheet.toString()));

                // Get my title     
                JSONObject myTitle = new JSONObject();
                myTitle.put("title_blocks", sheet.get("my-title"));
                
                // Get my notes
                JSONObject myNotes = new JSONObject();
                myNotes.put("my-notes", sheet.get("my-notes"));

This doesn't however work and while I get a json object with a key I get a null value for the value. I've also attempted to cast this into a JSONArray but then I get an error message saying that "java.util.LinkedHashMap cannot be cast to..". After reading a few posts I understand that the library doesn't have enough information to deserialise the object. But given the structure, I think that I would first need to get a JSON object and then single out the JSONArray. So the order would be:

1. get my-title JSONObject
2. get value of mytitle which is a JSONArray
3. Keep working down the document path

If there is a better way to do this I'm very much open to suggestions.

Thanks in advance!

If you use an online parser, like for example, jsonViewer you could see that your JSON is valid.

The library seems a false problem: while there are many better libraries that exists to parse JSON, json-simple while old could be a candidate at least to execute the task.

JSON file data is in composed of name/value pairs.

Data is separated by commas, curly braces hold objects, square brackets hold arrays and values could be of primitive type.

Here we have a single JSON Object named "characterizations_values" which holds an Array with one element.

A better solution would be to get the root element first while accessing the leafs from there.

    JSONParser jsonParser = new JSONParser();
    try (FileReader reader = new FileReader("yourfile.json"))
    {
        Object obj = jsonParser.parse(reader);
        JSONObject documentList = (JSONObject) obj;
    } catch (ParseException e) {
        e.printStackTrace();
    }