Parsing a nested JSON object containing changing keys

I am using Gson in java to parse a JSON file. The problem is that the json objects contain another set of objects. That wouldnt be a problem as I could just create another class and input into that. The problem is that these sub-objects include keys that can be different in each of them. I am unsure how to handle that.
Here's a cutout of the JSON:

[
  {
    "a": "aa",
    "b": 1,
    "c": "cc",
    "d": 2.2,
    "e": 3.3,
    "obj1": {"lu":1,"lo":1},
    "arr1": [],
    "obj2": {}
  },
   {
    "a": "aaa",
    "b": 4,
    "c": "ccc",
    "d": 5.5,
    "e": 6.6,
    "obj1": {"bli":1},
    "arr1": ["Some String"],
    "obj2": {
      "foo": 100,
      "bar": 50,
      "bla": 1
    }
  },
   {
    "a": "aaaa",
    "b": 7,
    "c": "cccc",
    "d": 8.8,
    "e": 9.9,
    "obj1": {},
    "arr1": ["Some String", "Another one"],
    "obj2": {
      "la": 300,
      "le": 20000
    }
  }
]

As you can see, obj1 and obj2 contain keys that are not consistent.
Here is my current code for the jObject class I parse that data into:

public class jObject {
	String a;
	Integer b;
	String c;
	Double d;
	Double e;
//	List<Pair<String,Integer>> obj1;
	List<String> arr1;
//	List<Pair<String,Integer>> obj2;
	
	public jObject(String a, Integer b, String c, Double d, Double e,
				   List<Pair<String,Integer>> obj1, List<String> arr1,List<Pair<String,Integer>> obj2) {
		this.a = a;
		this.b = b;
		this.c = c;
		this.d = d;
		this.e = e;
		
	//	this.obj1 = obj1;
		this.arr1 = arr1;
	//	this.obj2 = obj2;
				   }
}

It works for all the normal keys aswell as the "arr1" array.

Here is how I actually parse it if you want to know:

Gson gson = new Gson();

Reader reader = Files.newBufferedReader(Paths.get("PATH_TO_JSON"));
List<jObject> objects = gson.fromJson(reader, new TypeToken<List<jObject>>() {}.getType());

What I want to achieve is that "obj1" and "obj2" will be saved as part of the jObject class as Lists of a tuple of String and Integer.

I searched around for quite a bit but I couldnt find anything related to this exact problem.

Thanks in advance!

You can use Map.

public class jObject {
    String a;
    Integer b;
    String c;
    Double d;
    Double e;
    Map<String,Integer> obj1;
    List<String> arr1;
    Map<String,Integer> obj2;

    public jObject(String a, Integer b, String c, Double d, Double e,
                   Map<String,Integer> obj1, List<String> arr1, Map<String,Integer> obj2) {
        this.a = a;
        this.b = b;
        this.c = c;
        this.d = d;
        this.e = e;

        this.obj1 = obj1;
        this.arr1 = arr1;
        this.obj2 = obj2;
    }
}

JsonObject cannot be easily parsed into list or array. But it can be easily parsed to a Map, e.g. Map<String, Integer> that can be manually transformed into Set<Map.Entry<String, Integer>> using entrySet() method.

A more difficult way is to implement your own deserializer for a particular type, e.g. List of pairs.