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org.json.JSONException: JSONObject["status"] is not a JSONObject

I am now currently using a weather API from http://wiki.swarma.net/index.php?title=%E5%BD%A9%E4%BA%91%E5%A4%A9%E6%B0%94API/v2 and wished to convert the JSONObject into printable Strings. However, when I am working on the following code, two errors occurred:
public class getApi {
private static final String WEATHER_MAP_URL = "https://api.caiyunapp.com/v2/TAkhjf8d1nlSlspN/121.6544,25.1552/realtime.json";
private static final String WEATHER_TEST_API = "TAkhjf8d1nlSlspN";
public static JSONObject getWeatherJson() {
try {
URL url = new URL( WEATHER_MAP_URL );
HttpURLConnection connection =
(HttpURLConnection)url.openConnection();
connection.addRequestProperty( "x-api-key", WEATHER_TEST_API );
BufferedReader reader = new BufferedReader(
new InputStreamReader( connection.getInputStream()) );
StringBuffer json = new StringBuffer( 1024 );
String tmp;
while( (tmp = reader.readLine()) != null )
json.append(tmp).append("\n");
reader.close();
JSONObject data = new JSONObject( json.toString() );
if(data.getJSONObject("status").toString() != "ok" ) {
return null;
}
return data;
}
catch(Exception e) {
e.printStackTrace();
return null;
}
}
public static void main( String[] args ) {
JSONObject WeatherJson = getWeatherJson();
try {
JSONArray details = WeatherJson.getJSONObject("result").getJSONObject("hourly").
getJSONArray("skycon");
System.out.println(details.getJSONObject(0).getJSONObject("value").toString());
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
The JSONObject structure, which is also shown in the link above, is like this:
{
"status":"ok",
"lang":"zh_CN",
"server_time":1443418212,
"tzshift":28800,
"location":[
25.1552, //latitude
121.6544 //longitude
],
"unit":"metric",
"result":{
"status":"ok",
"hourly":{
"status":"ok",
"skycon":[
{
"value":"Rain",
"datetime":"2015-09-28 13:00"
},
{
...
}]
}
}
}
The error occurred:
org.json.JSONException: JSONObject["status"] is not a JSONObject.
at org.json.JSONObject.getJSONObject(JSONObject.java:557)
at getApi.getWeatherJson(getApi.java:34)
at getApi.main(getApi.java:45)
Exception in thread "main" java.lang.NullPointerException
at getApi.main(getApi.java:47)
I have looked at similar posts on the topic is not a JSONObject Exception but found that none of them can help me. I suspect that something is wrong with requesting the data, so actually, getWeatherJson() returns a null object and results in the NullPointerException and JSONObjectException.
Can anyone help me with the code?

According to the getJSONObject() Javadoc, this method will throw an exception if the returned object isn't a true JSON object, which it isn't because "status" is a string. As such, try using data.getString("status").

The status field in the JSON document you have posted is not an object. In JSON, objects are enclosed in with {} brackets. The result node however, is a nested object which holds the status key/value pair. Try the following:
JSONObject data = new JSONObject(json.toString());
if(data.getJSONObject("result").get("status").toString() != "ok" ) {
return null;
}

Null while getting string from json file

I am using json simple
this is my code:
public static String getDetails() {
String name = System.getProperty("user.name");
JSONParser parser = new JSONParser();
File dir = new File("C:\\Users\\" + name + "\\AppData\\Roaming\\.minecraft\\launcher_profiles.json");
if (dir.exists()) {
Object obj = null;
try {
obj = parser.parse(new FileReader("C:\\Users\\" + name + "\\AppData\\Roaming\\.minecraft\\launcher_profiles.json"));
} catch (Exception e) {
e.printStackTrace();
}
JSONObject jsonObject = (JSONObject) obj;
String da = (String) jsonObject.get("username");
try {
return obj.toString() + "\n" + da;
} catch (Exception e) {
e.printStackTrace();
}
} else {
System.out.println("dir no exist");
}
return null;
}
when i print this out it returns all the text in the json file and it returns null from String 'da' I dont know why because its not null it exist in the file??
JSON file: https://hastebin.com/sirefacado.json

To access the username you have to use the fully qualified path. In your case that is:
String da = (String) ((JSONObject)((JSONObject)jsonObject.get("authenticationDatabase")).get("d46e53840f3f41a2b9e44e2d4d72ebeb")).get("username");
That is, because your username is encapsulated in the following part of the JSON file:
authenticationDatabase: {
d46e53840f3f41a2b9e44e2d4d72ebeb: {
accessToken: "86ccdfsdfsdfsc2c38ec6012a1ccfsdfR",
username: "privater#email.co",
profiles: {
ad4fa7102fb7432cb4e07d471e348c77: {
displayName: "hio"
}
}
}
}
To access the username via the token you have to go via the authenticationDatabase. It may be the case that there are multiple ids, therefore you have to iterate over all the existing ones
For that you can do
JSONObject authDatabase = (JSONObject) jsonObject.get("authenticationDatabase");
for(Object id : authDatabase.keySet()) {
JSONObject authEntry = (JSONObject) authDatabase.get(id);
String username = (String) authDatabase.get("username");
/* now do something with the username.
You can abort after you found the first username
and store it in the da object, or create a list
of existing usernames, ... */
}

Following are the top level keys in the JSON you posted.
{
"settings": {...some data...},
"launcherVersion": {...some data...},
"clientToken": "dbf69db062d5d32b093e7d67ce744d60",
"profiles": {...some data...},
"analyticsFailcount": 0,
"analyticsToken": "f18d7c0f152f5ad44b2a6525e0d5cfa9",
"selectedProfile": "OptiFine",
"authenticationDatabase": {...some data...},
"selectedUser": {...some data...}
}
Your code tries to extract the value of username from the top level.
String da = (String) jsonObject.get("username")
It doesn't contain the key username. Hence, it is print null.

Your statement below is trying to fetch an element named "username" from the root JSON object however, your actual value is nested inside.
String da = (String) jsonObject.get("username");
{
"authenticationDatabase": {
"d46e53840f3f41a2b9e44e2d4d72ebeb": {
"accessToken": "86ccdfsdfsdfsc2c38ec6012a1ccfsdfR",
"username": "privater#email.co",
"profiles": {
"ad4fa7102fb7432cb4e07d471e348c77": {
"displayName": "hio"
}
}
}
}
}
In order to fetch inner element, you need to drill down as follows. Understand that it is not an good idea to hard cord the key inside the "authenticationDatabase" object.
JSONObject jsonObject = (JSONObject) obj;
String da;
try {
JSONObject adb = (JSONObject) jsonObject.get("authenticationDatabase");
JSONObject adbKey = null;
for(Object key:adb.keySet()) {
String sKey = (String) key;
adbKey = (JSONObject) adb.get(sKey);
da = (String) adbKey.get("username");
return obj.toString() + "\n" + da;
}
} catch (Exception e) {
e.printStackTrace();
}

JestResult can't parse my custom JsonObject

I am trying to write unit tests for my JestClient wrapper. To do so, I created a JestResult object where I set a custom JsonObject that has my expected output. However, the JestResult cannot parse my JsonObject. The issue is in the following JestResult method:
protected <T> T createSourceObject(JsonElement source, Class<T> type) {
T obj = null;
try {
String json = source.toString();
obj = gson.fromJson(json, type);
// Check if JestId is visible
Field[] fields = type.getDeclaredFields();
for (Field field : fields) {
if (field.isAnnotationPresent(JestId.class)) {
try {
field.setAccessible(true);
Object value = field.get(obj);
if (value == null) {
Class<?> fieldType = field.getType();
JsonElement id = ((JsonObject) source).get(ES_METADATA_ID);
field.set(obj, getAs(id, fieldType));
}
} catch (IllegalAccessException e) {
log.error("Unhandled exception occurred while getting annotated id from source");
}
break;
}
}
} catch (Exception e) {
log.error("Unhandled exception occurred while converting source to the object ." + type.getCanonicalName(), e);
}
return obj;
}
Specifically, the line
obj = gson.fromJson(json, type);
This line sets all fields of obj to null. However, if I use the same line in my own code, all fields are properly initialized. I am using
Jest: 0.1.6
Gson: 2.3.1

How to throw a parseException in a switch statement?

To increase my projects code coverage, I need to reach the branch ParseException in this method:
public String filterMessage(String actionIn, String messageIn) {
String message = null;
try{
switch (actionIn) {
//EDIT: this calls the other class causing parseexception
case "search":
message = (srvmt.SearchEngine(messageIn));
break;
default:
message = messageIn;
break;
}
}catch (ParseException e) {
System.out.println("Encountered parse exception");
e.printStackTrace();
}catch(IOException ioException){
ioException.printStackTrace();
}
return message;
}
Instincts are that we must put a String that is "illegal", that can't be parsed because it isn't actually a String, but how do you place something like that without causing a compile error (like putting an int to cause faulse parsing). Any ideas how to test this catch "branch"?
EDIT: This is the method the case above calls which uses a parse exception
public String SearchEngine(String removecommand)
{//INCOMING-SEARCH¿Email¿#gmail.com
JSONArray databaseupdated = read(pathdatabase);
ArrayList<String> matchlist = new ArrayList<String>();
JSONObject mainobj = new JSONObject();
JSONArray userinfo = new JSONArray();
JSONObject obj = new JSONObject();
for(int i = 0; i<databaseupdated.size(); i++)
{
String option = "";
String value = "";
try {
JSONObject json = (JSONObject) new JSONParser().parse(removecommand);
option = (String) json.get("option");
value = (String) json.get("value");
mainobj= (JSONObject) new JSONParser().parse(databaseupdated.get(i).toString());
userinfo =(JSONArray) new JSONParser().parse(mainobj.get(mainobj.keySet().toString().substring(1,mainobj.keySet().toString().length()-1)).toString());
obj = (JSONObject) new JSONParser().parse(userinfo.get(0).toString());
} //EDIT, there is a lot of code not explained, but here is the parse EXCEPTION
catch (ParseException e) {
return "false";
}
if(SearchEngineTRUEFALSE1(mainobj.keySet().toString().substring(1,mainobj.keySet().toString().length()-1),option,value))
{
matchlist.add(obj.get("Email").toString());
}
}
return matchlist.toString();
}

Try this :
throw new ParseException("Parse exception description you want");

you could throw an exception as Michaël told and if you are using Junit to test, you could do something like this using the expected annotation to catch it
#Test(expected= ParseException)
public void testFilterMessage() {
filterMessage(illformedString1, illformedString2);
}

Given your updated question:
You want to look into using a mocking framework.
Basically you have to enable your class under test so that you can provide a mocked srvmt object to it. And you configure that mock to simply throw that exception upon calls to the method it owns. Well, one of your test case configures the mock to throw that exception; other testcases would configure the mock to return other results.
In other words: search for terms like "dependency injection" and "mocking"; study and apply.

How to parse a JSON Input stream

I am using java to call a url that returns a JSON object:
url = new URL("my URl");
urlInputStream = url.openConnection().getInputStream();
How can I convert the response into string form and parse it?

I would suggest you have to use a Reader to convert your InputStream in.
BufferedReader streamReader = new BufferedReader(new InputStreamReader(in, "UTF-8"));
StringBuilder responseStrBuilder = new StringBuilder();
String inputStr;
while ((inputStr = streamReader.readLine()) != null)
responseStrBuilder.append(inputStr);
new JSONObject(responseStrBuilder.toString());
I tried in.toString() but it returns:
getClass().getName() + '#' + Integer.toHexString(hashCode())
(like documentation says it derives to toString from Object)

All the current answers assume that it is okay to pull the entire JSON into memory where the advantage of an InputStream is that you can read the input little by little. If you would like to avoid reading the entire Json file at once then I would suggest using the Jackson library (which is my personal favorite but I'm sure others like Gson have similar functions).
With Jackson you can use a JsonParser to read one section at a time. Below is an example of code I wrote that wraps the reading of an Array of JsonObjects in an Iterator. If you just want to see an example of Jackson, look at the initJsonParser, initFirstElement, and initNextObject methods.
public class JsonObjectIterator implements Iterator<Map<String, Object>>, Closeable {
private static final Logger LOG = LoggerFactory.getLogger(JsonObjectIterator.class);
private final InputStream inputStream;
private JsonParser jsonParser;
private boolean isInitialized;
private Map<String, Object> nextObject;
public JsonObjectIterator(final InputStream inputStream) {
this.inputStream = inputStream;
this.isInitialized = false;
this.nextObject = null;
}
private void init() {
this.initJsonParser();
this.initFirstElement();
this.isInitialized = true;
}
private void initJsonParser() {
final ObjectMapper objectMapper = new ObjectMapper();
final JsonFactory jsonFactory = objectMapper.getFactory();
try {
this.jsonParser = jsonFactory.createParser(inputStream);
} catch (final IOException e) {
LOG.error("There was a problem setting up the JsonParser: " + e.getMessage(), e);
throw new RuntimeException("There was a problem setting up the JsonParser: " + e.getMessage(), e);
}
}
private void initFirstElement() {
try {
// Check that the first element is the start of an array
final JsonToken arrayStartToken = this.jsonParser.nextToken();
if (arrayStartToken != JsonToken.START_ARRAY) {
throw new IllegalStateException("The first element of the Json structure was expected to be a start array token, but it was: " + arrayStartToken);
}
// Initialize the first object
this.initNextObject();
} catch (final Exception e) {
LOG.error("There was a problem initializing the first element of the Json Structure: " + e.getMessage(), e);
throw new RuntimeException("There was a problem initializing the first element of the Json Structure: " + e.getMessage(), e);
}
}
private void initNextObject() {
try {
final JsonToken nextToken = this.jsonParser.nextToken();
// Check for the end of the array which will mean we're done
if (nextToken == JsonToken.END_ARRAY) {
this.nextObject = null;
return;
}
// Make sure the next token is the start of an object
if (nextToken != JsonToken.START_OBJECT) {
throw new IllegalStateException("The next token of Json structure was expected to be a start object token, but it was: " + nextToken);
}
// Get the next product and make sure it's not null
this.nextObject = this.jsonParser.readValueAs(new TypeReference<Map<String, Object>>() { });
if (this.nextObject == null) {
throw new IllegalStateException("The next parsed object of the Json structure was null");
}
} catch (final Exception e) {
LOG.error("There was a problem initializing the next Object: " + e.getMessage(), e);
throw new RuntimeException("There was a problem initializing the next Object: " + e.getMessage(), e);
}
}
#Override
public boolean hasNext() {
if (!this.isInitialized) {
this.init();
}
return this.nextObject != null;
}
#Override
public Map<String, Object> next() {
// This method will return the current object and initialize the next object so hasNext will always have knowledge of the current state
// Makes sure we're initialized first
if (!this.isInitialized) {
this.init();
}
// Store the current next object for return
final Map<String, Object> currentNextObject = this.nextObject;
// Initialize the next object
this.initNextObject();
return currentNextObject;
}
#Override
public void close() throws IOException {
IOUtils.closeQuietly(this.jsonParser);
IOUtils.closeQuietly(this.inputStream);
}
}
If you don't care about memory usage, then it would certainly be easier to read the entire file and parse it as one big Json as mentioned in other answers.

For those that pointed out the fact that you can't use the toString method of InputStream like this see https://stackoverflow.com/a/5445161/1304830 :
My correct answer would be then :
import org.json.JSONObject;
public static String convertStreamToString(java.io.InputStream is) {
java.util.Scanner s = new java.util.Scanner(is).useDelimiter("\\A");
return s.hasNext() ? s.next() : "";
}
...
JSONObject json = new JSONObject(convertStreamToString(url.openStream());

If you like to use Jackson Databind (which Spring uses by default for its HttpMessageConverters), then you may use the ObjectMapper.readTree(InputStream) API. For example,
ObjectMapper mapper = new ObjectMapper();
JsonNode json = mapper.readTree(myInputStream);

use jackson to convert json input stream to the map or object http://jackson.codehaus.org/
there are also some other usefull libraries for json, you can google: json java

Use a library.
GSON
Jackson
or one of many other JSON libraries that are out there.

Kotlin version with Gson
to read the response JSON:
val response = BufferedReader(
InputStreamReader(conn.inputStream, "UTF-8")
).use { it.readText() }
to parse response we can use Gson:
val model = Gson().fromJson(response, YourModelClass::class.java)

This example reads all objects from a stream of objects,
it is assumed that you need CustomObjects instead of a Map:
ObjectMapper mapper = new ObjectMapper();
JsonParser parser = mapper.getFactory().createParser( source );
if(parser.nextToken() != JsonToken.START_ARRAY) {
throw new IllegalStateException("Expected an array");
}
while(parser.nextToken() == JsonToken.START_OBJECT) {
// read everything from this START_OBJECT to the matching END_OBJECT
// and return it as a tree model ObjectNode
ObjectNode node = mapper.readTree(parser);
CustomObject custom = mapper.convertValue( node, CustomObject.class );
// do whatever you need to do with this object
System.out.println( "" + custom );
}
parser.close();
This answer was composed by using : Use Jackson To Stream Parse an Array of Json Objects and Convert JsonNode into Object

I suggest use javax.json.Json factory as less verbose possible solution:
JsonObject json = Json.createReader(yourInputStream).readObject();
Enjoy!

if you have JSON file you can set it on assets folder then call it using this code
InputStream in = mResources.getAssets().open("fragrances.json");
// where mResources object from Resources class

{
InputStream is = HTTPClient.get(url);
InputStreamReader reader = new InputStreamReader(is);
JSONTokener tokenizer = new JSONTokener(reader);
JSONObject jsonObject = new JSONObject(tokenizer);
}