'How to remove curly braces before writing JSON object in java
I am trying to make a simple JSON-DB in Java since the current library on maven is horrendously overcomplicated. I have this method that takes in a key and value to put into a JSONObject and write it to my database.json file.
public static void put(String path, String key, Object[] value){
//creates new JSONObject where data will be stored
JSONObject jsondb = new JSONObject();
try{
//adds key and value to JSONObject
jsondb.put(key, value);
} catch (JSONException e){
e.printStackTrace();
} //end try-catch
try(PrintWriter out = new PrintWriter(new FileWriter(path, true))) {
out.write(jsondb.toString());
out.write(',');
} catch (Exception e){
e.printStackTrace();
} //end try-catch
} //end put()
Here is my main method where I write some data to the file
public static void main(String[] args) throws Exception {
String path = "app.json";
Object[] amogus = {"Hello", 1, 2, 3, 4, 5};
Object[] amogus1 = {"Hello", 1, 2, 3, 4, 5, 6, 7, 8, 9, 0};
JsonDB db = new JsonDB(path);
db.put(path, "arr", amogus);
db.put(path, "arr1", amogus1);
}
What happens is that it save each data in a set of curly braces. So when I write to the file more than once like I do in my main method it saves it like this:
{"arr": ["Hello", 1, 2, 3, 4, 5]}{"arr1": ["Hello", 1, 2, 3, 4, 5, 6, 7, 8, 9, 0]}
This causes VSCode to throw an error since this isnt valid JSON. How would I make the method remove the curly braces and add commas to make the above JSON valid JSON? I cant seem to find the documentation for this library (The library is org.json on maven).
Solution 1:[1]
I solved this problem by reading all of the content in the file and appending the JSON object that I wanted to write to the file and then write it all at once.
Solution 2:[2]
This is a syntax issue. Your json is not valid because the json syntax want your data to be between curly braces like this:
{
"arr": ["Hello", 1, 2, 3, 4, 5],
"arr1": ["Hello", 1, 2, 3, 4, 5, 6, 7, 8, 9, 0]
}
instead of this, which is not a valid json:
{"arr": ["Hello", 1, 2, 3, 4, 5]}
{"arr1": ["Hello", 1, 2, 3, 4, 5, 6, 7, 8, 9, 0]}
Create your data in your map object and let your json library convert (serialize) your object in a valid json.
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow
| Solution | Source |
|---|---|
| Solution 1 | AlexStan0 |
| Solution 2 | Harry Coder |
