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Exception is
java.lang.ClassCastException
:
org.json.JSONObject$Null
cannot be cast to
java.lang.String
Printthis>>>>>>userName=user1&passKey=12345678
POST Response Code :: 200
jsonObj>>>>>>>>>>>>>>>>>>{"response":{"roleTitle":"Parent","roleId":146,"passKey":"12345678","id":1,"userName":"user1"},"errorCode":null,"error":false,"message":null}
Jan 04, 2018 4:33:11 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [spring-dispatcher] in context with path [/balihans] threw exception [Request processing failed; nested exception is java.lang.ClassCastException: org.json.JSONObject$Null cannot be cast to java.lang.String] with root cause
java.lang.ClassCastException: org.json.JSONObject$Null cannot be cast to java.lang.String
at com.swasth.general.controller.SwasthController.postLogin(SwasthController.java:2274)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:777)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:706)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:943)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:877)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:868)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1115)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Here is my postLogin code
@RequestMapping(value = "/login", method = RequestMethod.POST)
public ModelAndView postLogin(HttpServletRequest request,HttpServletRequest response) throws IOException, JSONException {
ModelAndView addmodel = new ModelAndView("login");
String uri = "http://localhost:8080/login/api/";
URL url = new URL(uri);
HttpURLConnection con = (HttpURLConnection)url.openConnection();
con.setRequestMethod("POST");
String userName = request.getParameter("userName");
String passKey = request.getParameter("passKey");
con.setDoOutput(true);
OutputStream os = con.getOutputStream();
os.write(("userName=" + userName + "&passKey=" + passKey).getBytes());
System.out.println("Printthis>>>>>>" + "userName=" + userName + "&passKey=" + passKey);
os.flush();
os.close();
int responseCode = con.getResponseCode();
System.out.println("POST Response Code :: " + responseCode);
BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer responses = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
responses.append(inputLine);
//System.out.println("responses>>>>>>>>>>>"+responses);
String str = responses.toString();
JSONObject jsonObj = new JSONObject(str);
System.out.println("jsonObj>>>>>>>>>>>>>>>>>>"+jsonObj);
String res = (String)jsonObj.get("errorCode");
// build a JSON object
List<PatentLoginInfo> PatentLoginInfoArray = new ArrayList<PatentLoginInfo>();
ObjectMapper mapper = new ObjectMapper();
RestTemplate restTemplate = new RestTemplate();
String res11 = (String)jsonObj.get("response");
String login = restTemplate.getForObject(uri, String.class);
JSONObject obj = new JSONObject(login);
JSONObject objects = obj.getJSONObject(res11);
System.out.println("objects>>>>>>>>>>>>>>>>>>>>>>>>>>>>>"+objects);
PatentLoginInfo patentLoginInfo = mapper.readValue(objects.toString(), PatentLoginInfo.class);
PatentLoginInfoArray.add(patentLoginInfo);
addmodel.addObject("theLogin", PatentLoginInfoArray);
if (res.equals("BVE000403")) { // success
addmodel = new ModelAndView("index");
addmodel.addObject("login Unsucessfull","Password is invalid");
return addmodel;
else{
addmodel = new ModelAndView("AnswerQuestion");
addmodel.addObject("login sucessfull");
return addmodel;
–
JSONObject has a specific inner constant for representing null objects: JSONObject.NULL
Before casting your JSONObject to a String, you may verify if it equals the NULL constant. Here an example:
//put words from JSON to array
for (int i = 0; i<wordsInJSONArray.length(); i++) {
Object o = wordsInJSONArray.get(i);
if (!JSONObject.NULL.equals(o)) {
String word = (String) o;
this.wordsArray[i] = word;
–
You could also use isNull()
Returns true if the associated value for the specified name is JsonValue.NULL. More here
So your code would be:
String code = jsonObj.isNull("errorCode") ? "" : jsonObj.getJsonString("errorCode");
It seems that "errorCode" is null from your print :
{"roleTitle":"Parent","roleId":146,"passKey":"12345678","id":1,"userName":"user1"},"errorCode":null,"error":false,"message":null}
So you need to check on null before casting to string
String res = (String)jsonObj.get("errorCode");
so apply the following validation and it will work :
String res = null;
if (!org.json.JSONObject.NULL.equals(jsonObj.opt("errorCode")) && jsonObj.getString("errorCode") != null) {
res = jsonObj.getString("errorCode");
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