CODEWITHSUNDEEP
javarestspring-restcontroller
lyancsie
lyancsie

Reputation: 678

Huge JSON returned instead of a simple one

I'm writing really basic algorithms to understand Rest better.

I have written the following code: 

@RestController
class DoubleController {

  @GetMapping("/doubling")
  public Object doubling(@RequestParam Integer input) {
    if (input != null) {
      return new DoubledValue(input);
    }
    return new Error("Please provide an input");
  }
}

Though it works well if the input is given, but otherwise it returns a huge JSON, not only the expected one. My Error class has got only one field, and I would like to return something like

{
 "error": "Please provide an input!"
}

The JSON message I get is the following:

{"cause":null,"stackTrace":[{"methodName":"doubling","fileName":"DoubleController.java","lineNumber":16,"className":"com.example.demo.Controllers.DoubleController","nativeMethod":false},{"methodName":"invoke0","fileName":"NativeMethodAccessorImpl.java","lineNumber":-2,"className":"sun.reflect.NativeMethodAccessorImpl","nativeMethod":true},{"methodName":"invoke","fileName":"NativeMethodAccessorImpl.java","lineNumber":62,"className":"sun.reflect.NativeMethodAccessorImpl","nativeMethod":false},{"methodName":"invoke","fileName":"DelegatingMethodAccessorImpl.java","lineNumber":43,"className":"sun.reflect.DelegatingMethodAccessorImpl","nativeMethod":false},{"methodName":"invoke","fileName":"Method.java","lineNumber":498,"className":"java.lang.reflect.Method","nativeMethod":false},{"methodName":"doInvoke","fileName":"InvocableHandlerMethod.java","lineNumber":189,"className":"org.springframework.web.method.support.InvocableHandlerMethod","nativeMethod":false},{"methodName":"invokeForRequest","fileName":"InvocableHandlerMethod.java","lineNumber":138,"className":"org.springframework.web.method.support.InvocableHandlerMethod","nativeMethod":false},{"methodName":"invokeAndHandle","fileName":"ServletInvocableHandlerMethod.java","lineNumber":102,"className":"org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod","nativeMethod":false},{"methodName":"invokeHandlerMethod","fileName":"RequestMappingHandlerAdapter.java","lineNumber":895,"className":"org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter","nativeMethod":false},{"methodName":"handleInternal","fileName":"RequestMappingHandlerAdapter.java","lineNumber":800,"className":"org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter","nativeMethod":false},{"methodName":"handle","fileName":"AbstractHandlerMethodAdapter.java","lineNumber":87,"className":"org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter","nativeMethod":false},{"methodName":"doDispatch","fileName":"DispatcherServlet.java","lineNumber":1038,"className":"org.springframework.web.servlet.DispatcherServlet","nativeMethod":false},{"methodName":"doService","fileName":"DispatcherServlet.java","lineNumber":942,"className":"org.springframework.web.servlet.DispatcherServlet","nativeMethod":false},{"methodName":"processRequest","fileName":"FrameworkServlet.java","lineNumber":1005,"className":"org.springframework.web.servlet.FrameworkServlet","nativeMethod":false},{"methodName":"doGet","fileName":"FrameworkServlet.java","lineNumber":897,"className":"org.springframework.web.servlet.FrameworkServlet","nativeMethod":false},{"methodName":"service","fileName":"HttpServlet.java","lineNumber":634,"className":"javax.servlet.http.HttpServlet","nativeMethod":false},{"methodName":"service","fileName":"FrameworkServlet.java","lineNumber":882,"className":"org.springframework.web.servlet.FrameworkServlet","nativeMethod":false},{"methodName":"service","fileName":"HttpServlet.java","lineNumber":741,"className":"javax.servlet.http.HttpServlet","nativeMethod":false},{"methodName":"internalDoFilter","fileName":"ApplicationFilterChain.java","lineNumber":231,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"doFilter","fileName":"ApplicationFilterChain.java","lineNumber":166,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"doFilter","fileName":"WsFilter.java","lineNumber":53,"className":"org.apache.tomcat.websocket.server.WsFilter","nativeMethod":false},{"methodName":"internalDoFilter","fileName":"ApplicationFilterChain.java","lineNumber":193,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"doFilter","fileName":"ApplicationFilterChain.java","lineNumber":166,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"doFilterInternal","fileName":"RequestContextFilter.java","lineNumber":99,"className":"org.springframework.web.filter.RequestContextFilter","nativeMethod":false},{"methodName":"doFilter","fileName":"OncePerRequestFilter.java","lineNumber":107,"className":"org.springframework.web.filter.OncePerRequestFilter","nativeMethod":false},{"methodName":"internalDoFilter","fileName":"ApplicationFilterChain.java","lineNumber":193,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"doFilter","fileName":"ApplicationFilterChain.java","lineNumber":166,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"doFilterInternal","fileName":"FormContentFilter.java","lineNumber":92,"className":"org.springframework.web.filter.FormContentFilter","nativeMethod":false},{"methodName":"doFilter","fileName":"OncePerRequestFilter.java","lineNumber":107,"className":"org.springframework.web.filter.OncePerRequestFilter","nativeMethod":false},{"methodName":"internalDoFilter","fileName":"ApplicationFilterChain.java","lineNumber":193,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"doFilter","fileName":"ApplicationFilterChain.java","lineNumber":166,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"doFilterInternal","fileName":"HiddenHttpMethodFilter.java","lineNumber":93,"className":"org.springframework.web.filter.HiddenHttpMethodFilter","nativeMethod":false},{"methodName":"doFilter","fileName":"OncePerRequestFilter.java","lineNumber":107,"className":"org.springframework.web.filter.OncePerRequestFilter","nativeMethod":false},{"methodName":"internalDoFilter","fileName":"ApplicationFilterChain.java","lineNumber":193,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"doFilter","fileName":"ApplicationFilterChain.java","lineNumber":166,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"doFilterInternal","fileName":"CharacterEncodingFilter.java","lineNumber":200,"className":"org.springframework.web.filter.CharacterEncodingFilter","nativeMethod":false},{"methodName":"doFilter","fileName":"OncePerRequestFilter.java","lineNumber":107,"className":"org.springframework.web.filter.OncePerRequestFilter","nativeMethod":false},{"methodName":"internalDoFilter","fileName":"ApplicationFilterChain.java","lineNumber":193,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"doFilter","fileName":"ApplicationFilterChain.java","lineNumber":166,"className":"org.apache.catalina.core.ApplicationFilterChain","nativeMethod":false},{"methodName":"invoke","fileName":"StandardWrapperValve.java","lineNumber":199,"className":"org.apache.catalina.core.StandardWrapperValve","nativeMethod":false},{"methodName":"invoke","fileName":"StandardContextValve.java","lineNumber":96,"className":"org.apache.catalina.core.StandardContextValve","nativeMethod":false},{"methodName":"invoke","fileName":"AuthenticatorBase.java","lineNumber":490,"className":"org.apache.catalina.authenticator.AuthenticatorBase","nativeMethod":false},{"methodName":"invoke","fileName":"StandardHostValve.java","lineNumber":139,"className":"org.apache.catalina.core.StandardHostValve","nativeMethod":false},{"methodName":"invoke","fileName":"ErrorReportValve.java","lineNumber":92,"className":"org.apache.catalina.valves.ErrorReportValve","nativeMethod":false},{"methodName":"invoke","fileName":"StandardEngineValve.java","lineNumber":74,"className":"org.apache.catalina.core.StandardEngineValve","nativeMethod":false},{"methodName":"service","fileName":"CoyoteAdapter.java","lineNumber":343,"className":"org.apache.catalina.connector.CoyoteAdapter","nativeMethod":false},{"methodName":"service","fileName":"Http11Processor.java","lineNumber":408,"className":"org.apache.coyote.http11.Http11Processor","nativeMethod":false},{"methodName":"process","fileName":"AbstractProcessorLight.java","lineNumber":66,"className":"org.apache.coyote.AbstractProcessorLight","nativeMethod":false},{"methodName":"process","fileName":"AbstractProtocol.java","lineNumber":791,"className":"org.apache.coyote.AbstractProtocol$ConnectionHandler","nativeMethod":false},{"methodName":"doRun","fileName":"NioEndpoint.java","lineNumber":1417,"className":"org.apache.tomcat.util.net.NioEndpoint$SocketProcessor","nativeMethod":false},{"methodName":"run","fileName":"SocketProcessorBase.java","lineNumber":49,"className":"org.apache.tomcat.util.net.SocketProcessorBase","nativeMethod":false},{"methodName":"runWorker","fileName":"ThreadPoolExecutor.java","lineNumber":1149,"className":"java.util.concurrent.ThreadPoolExecutor","nativeMethod":false},{"methodName":"run","fileName":"ThreadPoolExecutor.java","lineNumber":624,"className":"java.util.concurrent.ThreadPoolExecutor$Worker","nativeMethod":false},{"methodName":"run","fileName":"TaskThread.java","lineNumber":61,"className":"org.apache.tomcat.util.threads.TaskThread$WrappingRunnable","nativeMethod":false},{"methodName":"run","fileName":"Thread.java","lineNumber":748,"className":"java.lang.Thread","nativeMethod":false}],"localizedMessage":"Please provide an input","message":"Please provide an input","suppressed":[]}

How should I solve this issue? Thank you in advance.

Upvotes: 0

Views: 284

Answers (2)

Jonathan JOhx
Jonathan JOhx

Reputation: 5968

Please make sure that you have a class called Error and you have imported it in DoubleController class. 

 public class Error implements Serializable {
     private String message;
     public Error() {
     }
     public Error(String message) {
          this.message = message;
     }
     public String getMessage() {
          return message;
     } 
     public void setMessage(String message) {
          this.message = message ;
     } 
 }

 import com.yourproject.models.Error;
 @RestController
 class DoubleController {
   ..... 
 }

Upvotes: 1

Chris Thompson
Chris Thompson

Reputation: 35598

The "huge" JSON you're getting is a default Spring Boot error message, likely because it can't find a route that matches. By default, your handler method is expecting some argument. If none is provided, it fails to find your handler method.

Try changing it to:

public Object doubling(@RequestParam(required=false) Integer input) {

Upvotes: 1

Related Questions