How to write 2 two-dimensional array to json object in java using json-simple?

Question

I'm setting up a java game server request handler that get json messages and send back relevant json message as response. In some cases I need to send 2 dimensional String array as the game board. I'm having a problem to do that using json-simple. Further more, how to parse it to a board in the client side afterwards? Thanks.

char[][] charArray; //initialised  
JSONObject jsonOut = new JSONObject();
ObjectOutputStream writer = new ObjectOutputStream(socket.getOutputStream());
JSONArray ja = new JSONArray() ;

ja.add(charArray);
jsonOut.put("board", ja);
writer.writeObject(jsonOut);

getting exception while ja.add(charArray);

Please state the nature of the "problem" you are having: what *specific" exception are you getting (a stack trace would be nice). — Scott Hunter, Jul 11 '19 at 12:34

score 1 · Answer 1 · answered Jul 11 '19 at 12:43

You are attempting to add an entire char[][] array as a single element in JSONArray. You need to create a multi-dimensional JSONArray and map the char[][] character-by-character:

JSONArray jsonArray = new JSONArray();
for (char[] ca : charArray) {
  JSONArray arr = new JSONArray();
  for (char c : ca) {
    arr.add(Character.toString(c)); // or some other conversion
  }
  jsonArray.add(arr);
}

score 0 · Answer 2 · answered Jul 11 '19 at 12:37

0

You need to have a JsonArray of JsonArrays, the same way your String[][] is an array of arrays.

answered Jul 11 '19 at 12:37

ggfpc

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8

How to write 2 two-dimensional array to json object in java using json-simple?

2 Answers2