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Java - Access JSON Element (llegalFormatConversionException: d !=java.lang.String)

I am trying to learn JAVA and build a plugin for Minecraft; I have been successfully able to get the JSON data from my api endpoint however, the issue I am facing right now is an llegalFormatConversionException: d !=java.lang.String which means that the format I am trying to make into string isn't equal to the type of string that it's looking for.
I am trying to access a JSON element from my endpoint called condition
{
"todaysdate": "2021-02-12",
"temperature": 25,
"description": [
"Overcast"
],
"condition": 122,
}
Coming from C#; I know there's a website called json2sharp where you can create a root class for the JSON. I'm not sure how it would be applied in Java but currently, my code looks like this.
private String fetchWeather() throws IOException, InvalidConfigurationException {
// Download
final URL url = new URL(API);
final URLConnection request = url.openConnection();
// Set HEADER
request.setRequestProperty("x-api-key", plugin.apiKey);
request.setConnectTimeout(5000);
request.setReadTimeout(5000);
request.connect();
// Convert to a JSON object to print data
JsonParser jp = new JsonParser(); //from gson
JsonElement root = jp.parse(new InputStreamReader((InputStream) request.getContent())); //Convert the input stream to a json element
JsonObject rootobj = root.getAsJsonObject();
//JsonElement code = rootobj.get("condition");
String condition_code = rootobj.get("condition").toString();
plugin.getLogger().fine(String.format(
"[%s] Weather is %d",
world.getName(), condition_code
));
return condition_code;
}
If I call
private JsonObject fetchWeather() throws IOException, InvalidConfigurationException {
// Download
final URL url = new URL(API);
final URLConnection request = url.openConnection();
// Set HEADER
request.setRequestProperty("x-api-key", plugin.apiKey);
request.setConnectTimeout(5000);
request.setReadTimeout(5000);
request.connect();
// Convert to a JSON object to print data
JsonParser jp = new JsonParser(); //from gson
JsonElement root = jp.parse(new InputStreamReader((InputStream) request.getContent())); //Convert the input stream to a json element
JsonObject rootobj = root.getAsJsonObject();
return rootobj;
}
state = fetchWeather();
plugin.getLogger().warning(state.toString());
I do get the actual JSON with all of the elements so I know the URL and accessing it is completely working, but I get an llegalexception for format if I try to call and print with logger the condition code.
So, if I change the return type in fetchWeather() to be the root json object and then try to print it with the state variable above it works; but if I try to return the condition json element and print it it gives me an iilegal exception.
Now before I posted this question I did read some other questions people had but I couldn't get a working solution from their suggested answers. So, I am hoping someone can point me out on what I'm doing wrong because I know I'm messing up somewhere with the variable format.
Thanks.
Line 37: state = fetchWeather();
Line 103:
plugin.getLogger().fine(String.format(
"[%s] Weather is %d",
world.getName(), bId
));

condition_code variable is String. You should use the %s format specifier.

How can I encode JSON object content into a JSON string?

Trying to find a way to stringify a JSON string, with escape characters like JavaScript.
For example --
Input:
{"name":"Error","message":"hello"}
Output:
"{\"name\":\"Error\",\"message\":\"hello\"}"
I am able to get the object as JSON String using Gson, but not stringify (with escape characters).
Is this possible with Java?

Your input is a JSON object as text, presumably stored in a String. You're essentially trying to convert that text to a JSON string. So do just that.
String input = "{\"name\":\"Error\",\"message\":\"hello\"}";
System.out.println("Original JSON content: " + input);
Gson gson = new Gson();
String jsonified = gson.toJson(input);
System.out.println("JSONified: " + jsonified);
Since quotes (and other characters) must be escaped in JSON strings, the toJson will properly perform that transformation.
The code above will produce the
Original JSON content: {"name":"Error","message":"hello"}
JSONified: "{\"name\":\"Error\",\"message\":\"hello\"}"
In other words, jsonified now contains the content of a JSON string.
With Jackson, the process is the same, just serialize the String instance that contains your JSON object text
ObjectMapper mapper = new ObjectMapper();
StringWriter writer = new StringWriter();
mapper.writeValue(writer, input);
jsonified = writer.toString();
System.out.println("JSONified: " + jsonified);
produces
JSONified: "{\"name\":\"Error\",\"message\":\"hello\"}"

Another solution, I noted in comments:
Jackson's JsonStringEncoder.quoteAsString() Example: stackoverflow.com/a/40430760/639107

You can try this on your output json string :
String strWithEscChar = output.replaceAll("\"", "\\\\\"");

Parsing a JSONObject inside a JSONObject in a single line with json.simple

Lets say I want to parse a JSONObject with JSONObjects inside of it, which I parse from a string. I want to do this in a single line, like I've done with other libraries, but I'm not sure how.
JSONParser parser = new JSONParser();
Object obj = parser.parse(test);
JSONObject first = (JSONObject) obj;
JSONObject second = (JSONObject) first.get("feed");
JSONArray third = (JSONArray) second.get("entry");
JSONObject fourth = (JSONObject) third.get(0);
JSONObject fifth = (JSONObject) fourth.get("test");
Is there a way for me to get all these JSONObjects in a single line? With another library I'd just do first.getJSONObject("feed").getJSONArray("entry").getJSONObject(0) etc, but I'm not sure how to do it properly with this library.
Thanks.

I recommend use Gson (https://github.com/google/gson) Library from Google.

You can cast within a single line like this:
(JSONObject) ((JSONObject) YOURJSONOBJECT.get("YOUR_KEY")).get("ANOTHER_KEY");
This can get messy really quick depending on how many layers deep you have to go though

Getting java object back from JSON

I am putting some java objects in the Json at server side
like this :
ArrayList<VisjsNode>visjsNodes = new ArrayList<VisjsNode>();
ArrayList<VisjsConnection> visjsConnections = new ArrayList<VisjsConnection>();
String jsondata = null;
org.json.JSONObject object = new org.json.JSONObject();
try {
object.put("nodes", visjsNodes);
object.put("connections", visjsConnections);
jsondata = object.toString();
Now is there a way I can get these objects back from this json (jsondata) at client side
I am doing this:
com.google.gwt.json.client.JSONValue jsonValue = JSONParser.parseStrict(jsondata);
com.google.gwt.json.client.JSONObject jsonObject = jsonValue.isObject();
jsonValue = jsonObject.get("nodes");
Now I am trying this to get ArrayList back , by doing this
ArrayList<VisjsNode>visjsNodesFromjson = jsonValue ;
But its not compiling ,it says Incompatable types...
Can you please guide how we can retrieve the Java Object back from Json ..

That's because you're using two different JsonObject class. First you use the one which comes from org.json (org.json.JsonObject) and the other is com.google.gwt.json.client.JSONObject. Nevertheless, they're named similar, they're completely different classes.

JAVA JSONObject parsing issue

I am using JSONObject to parse nested JSON from an API example:
{"results":[{"congress":"112","state":"NJ","num_results":"2","offset":"0","members": [{"id":"L000123","first_name":"Frank"..........................
I am having trouble accessing the members nested area using JSONObject.
This is my code, any thoughts?
url= new URL("http://api.nytimes.com/svc/politics/v3/us/legislative/congress/112/senate/members.json?&state=NJ&api-key=7967107ef3c9e8d6c2f560027f87904e:17:65990356");
ByteArrayOutputStream urlOutputStream = new ByteArrayOutputStream();
IOUtils.copy(url.openStream(), urlOutputStream);
String urlContents = urlOutputStream.toString();
// parse the JSON object returned
JSONObject jsonO = new JSONObject(urlContents);
System.out.println(jsonO.toString());
JSONObject results = jsonO.getJSONObject("results");
JSONObject senators = results.getJSONObject("members");

You should use third party library like GSON.
http://code.google.com/p/google-gson/