What does this error 'org.springframework.http.converter.HttpMessageNotReadableException: Could not read JSON: Can not deserialize instance' mean?

Question

I am trying to send a JSON array to my server. My JSON array looks like this

["{"sourceAccountNo":"555555555555555","sourceBankCode":"GLBBNPKA","destinationBankCode":"GLBBNPKA","destinationBankAccountNo":"123456789111111","amount":5000,"narrationOne":"txn4 by maker 1","uniqueId":"ESW-COR:1405507591784"}"]

And the corresponding server side method is :

   @ResponseBody
    @ResponseStatus(value = HttpStatus.OK)
    @RequestMapping(value = "/xxx", method = RequestMethod.POST)
    public ResponseEntity<BulkCorporatePaymentResponse> xxx(@RequestBody BulkCorporatePaymentRequest corporatePaymentRequestList) {
            BulkCorporatePaymentResponse response = null;
            try {
                response = corporateApi.processBulkFundTransfer(corporatePaymentRequestList);
            } catch (Exception e) {

            }
            return new ResponseEntity<BulkCorporatePaymentResponse>(response, HttpStatus.OK);
        }

Now my BulkCorporatePaymentResponse and BulkCorporatePaymentRequest look like this

public class BulkCorporatePaymentResponse implements Serializable {

    private static final long serialVersionUID = -2026566288888889L;
    List<CorporatePaymentResponse> paymentResponseList;

    public List<CorporatePaymentResponse> getPaymentResponseList() {
        return paymentResponseList;
    }

    public void setPaymentResponseList(List<CorporatePaymentResponse> paymentResponseList) {
        this.paymentResponseList = paymentResponseList;
    }
}


public class BulkCorporatePaymentRequest implements Serializable {

    private static final long serialVersionUID = -202656628880099889L;
    private List<CorporatePaymentRequest> paymentRequestlist;

    public List<CorporatePaymentRequest> getPaymentRequestlist() {
        return paymentRequestlist;
    }

    public void setPaymentRequestlist(List<CorporatePaymentRequest> paymentRequestlist) {
        this.paymentRequestlist = paymentRequestlist;
    }

}

And my CorporatePaymentRequest looks liks this

public class CorporatePaymentRequest implements Serializable {




    private static final long serialVersionUID = 1346864799470440670L;

    private String sourceAccountNo;
    private String sourceBankCode;

    private String destinationBankCode;
    private String destinationBankAccountNo;

    private String corporateName;
    private double amount;
    private String remarks;

    private String narrationOne;
    private String narrationTwo;

    private String uniqueId;

    public String getSourceAccountNo() {
        return sourceAccountNo;
    }

    public void setSourceAccountNo(String sourceAccountNo) {
        this.sourceAccountNo = sourceAccountNo;
    }

    public String getSourceBankCode() {
        return sourceBankCode;
    }

    public void setSourceBankCode(String sourceBankCode) {
        this.sourceBankCode = sourceBankCode;
    }

    public String getDestinationBankCode() {
        return destinationBankCode;
    }

    public void setDestinationBankCode(String destinationBankCode) {
        this.destinationBankCode = destinationBankCode;
    }

    public String getDestinationBankAccountNo() {
        return destinationBankAccountNo;
    }

    public void setDestinationBankAccountNo(String destinationBankAccountNo) {
        this.destinationBankAccountNo = destinationBankAccountNo;
    }

    public String getCorporateName() {
        return corporateName;
    }

    public void setCorporateName(String corporateName) {
        this.corporateName = corporateName;
    }

    public double getAmount() {
        return amount;
    }

    public void setAmount(double amount) {
        this.amount = amount;
    }

    public String getRemarks() {
        return remarks;
    }

    public void setRemarks(String remarks) {
        this.remarks = remarks;
    }

    public String getNarrationOne() {
        return narrationOne;
    }

    public void setNarrationOne(String narrationOne) {
        this.narrationOne = narrationOne;
    }

    public String getNarrationTwo() {
        return narrationTwo;
    }

    public void setNarrationTwo(String narrationTwo) {
        this.narrationTwo = narrationTwo;
    }

    public String getUniqueId() {
        return uniqueId;
    }

    public void setUniqueId(String uniqueId) {
        this.uniqueId = uniqueId;
    }

}

And whenever i try to pass the above mentioned json array to my server I get the following exception

Jul 22, 2014 4:53:38 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [esewarest] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.http.converter.HttpMessageNotReadableException: Could not read JSON: Can not deserialize instance of com.esewa.server.corporate.schema.BulkCorporatePaymentRequest out of START_ARRAY token
 at [Source: org.apache.catalina.connector.CoyoteInputStream@72ced13f; line: 1, column: 1]; nested exception is org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of com.esewa.server.corporate.schema.BulkCorporatePaymentRequest out of START_ARRAY token
 at [Source: org.apache.catalina.connector.CoyoteInputStream@72ced13f; line: 1, column: 1]] with root cause
org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of com.esewa.server.corporate.schema.BulkCorporatePaymentRequest out of START_ARRAY token
 at [Source: org.apache.catalina.connector.CoyoteInputStream@72ced13f; line: 1, column: 1]
    at org.codehaus.jackson.map.JsonMappingException.from(JsonMappingException.java:163)
    at org.codehaus.jackson.map.deser.StdDeserializationContext.mappingException(StdDeserializationContext.java:219)
    at org.codehaus.jackson.map.deser.StdDeserializationContext.mappingException(StdDeserializationContext.java:212)
    at org.codehaus.jackson.map.deser.BeanDeserializer.deserializeFromArray(BeanDeserializer.java:869)
    at org.codehaus.jackson.map.deser.BeanDeserializer.deserialize(BeanDeserializer.java:597)
    at org.codehaus.jackson.map.ObjectMapper._readMapAndClose(ObjectMapper.java:2725)
    at org.codehaus.jackson.map.ObjectMapper.readValue(ObjectMapper.java:1916)
    at org.springframework.http.converter.json.MappingJacksonHttpMessageConverter.readInternal(MappingJacksonHttpMessageConverter.java:122)
    at org.springframework.http.converter.AbstractHttpMessageConverter.read(AbstractHttpMessageConverter.java:153)
    at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.readWithMessageConverters(HandlerMethodInvoker.java:641)
    at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveRequestBody(HandlerMethodInvoker.java:605)
    at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveHandlerArguments(HandlerMethodInvoker.java:354)
    at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:171)
    at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:436)
    at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:424)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:789)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:206)
    at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:179)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:311)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:116)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:101)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:113)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:139)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:45)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter(BasicAuthenticationFilter.java:150)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:182)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:125)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
    at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:173)
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at com.esewa.server.web.filter.GWTCacheControlFilter.doFilter(GWTCacheControlFilter.java:36)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1001)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:579)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
    at java.lang.Thread.run(Thread.java:662)

Any suggestion would be of great help.

UPDATE by editor (Mona Jalal): On a side note I get this error when posting raspi IP to Postman and click on the send button:

144.92.129.230:8080/api/devices

{
  "timestamp": 1457494478717,
  "status": 400,
  "error": "Bad Request",
  "exception": "org.springframework.http.converter.HttpMessageNotReadableException",
  "message": "Required request body content is missing: org.springframework.web.method.HandlerMethod$HandlerMethodParameter@53cb13b3",
  "path": "/api/devices"
}

Answer 1

Clearly, the JSON parser is unable to parse your JSON. Try validating the JSON at http://jsonlint.com/ to see what the problem is.

As others have mentioned, you have an extraneous set of quotes just inside your initial square brackets.

You must remove these. If the conversion still doesn't work, you may have additional problems with the mapping of your JSON to your object, but don't confuse the two issues and put the quotes back - you will get nowhere with that approach - you need valid JSON first, then you can work on making sure that the valid JSON can be deserialized into the expected object.

Perhaps a unit test for the JSON deserialization is in order?