java.lang.ClassCastException: java.util.LinkedHashMap ढाला नहीं जा सकता

Question

जावास्क्रिप्ट

$.ajax({  
    headers : { 
     'Accept' : 'application/json' , 
     'Content-Type' : 'application/json' 
    }, 
    url   : "/realgrid/product/addOd.do", 
    type  : "post", 
    data  : JSON.stringify(JsonOrderDetailValues), 
    dataType : "json", 
    success  : function(data){ 
     var json = eval(data); 
     if (json.result == 1) { 
       alert("insert."); 
     }else if(json.result == 2){ 
       alert("update.") 
     }else { 
      alert("error."); 
     } 
    }, 
    error : function(request,status,error){ 
     alert("code:"+request.status+"\n"+"error:"+error); 
    } 
}); 

console.log (JsonOrderDetailValues)

[Object, Object, Object, Object] 
0: Object 
categoryCode: "AC-MV" 
categoryName: undefined 
costPrice: 168050 
date: undefined 
modelCode: "YP-GB70" 
modelName: undefined 
no: 1 
number: "201309120932" 
total: 88 
totalPrice: 14788400 
typeCode: "AV" 
typeName: undefined 
unitPrice: 294500 
__proto__: Object 
1: Object 
2: Object 
3: Object 

जावा वसंत नियंत्रक

@RequestMapping (value="/addOd.do",method=RequestMethod.POST) 
public ModelAndView addOdMaster(@RequestBody List<OrderDetails> od){ 

     //java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast 
    System.out.println(od.get(0).getNumber()); 

    Map<String, Integer> result = new HashMap<String,Integer>(); 
    result.put("result", 0); 
    return new ModelAndView("jsonView",result); 
} 

VO

public class OrderDetails { 
private String number; 
private int no; 
private String typeCode; 
private String categoryCode; 
private String modelCode; 
private int total; 
private int costPrice; 
private int unitPrice; 
private int totalPrice; 


public int getTotalPrice() { 
    return totalPrice; 
} 
public void setTotalPrice(int totalPrice) { 
    this.totalPrice = totalPrice; 
} 
public String getNumber() { 
    return number; 
} 
public void setNumber(String number) { 
    this.number = number; 
} 
public int getNo() { 
    return no; 
} 
public void setNo(int no) { 
    this.no = no; 
} 
public String getTypeCode() { 
    return typeCode; 
} 
public void setTypeCode(String typeCode) { 
    this.typeCode = typeCode; 
} 
public String getCategoryCode() { 
    return categoryCode; 
} 
public void setCategoryCode(String categoryCode) { 
    this.categoryCode = categoryCode; 
} 
public String getModelCode() { 
    return modelCode; 
} 
public void setModelCode(String modelCode) { 
    this.modelCode = modelCode; 
} 
public int getTotal() { 
    return total; 
} 
public void setTotal(int total) { 
    this.total = total; 
} 
public int getCostPrice() { 
    return costPrice; 
} 
public void setCostPrice(int costPrice) { 
    this.costPrice = costPrice; 
} 
public int getUnitPrice() { 
    return unitPrice; 
} 
public void setUnitPrice(int unitPrice) { 
    this.unitPrice = unitPrice; 
} 
} 

त्रुटि संदेश

FATAL: Servlet.service() for servlet [dispatcher] in context with path [/realgrid] threw exception [Request processing failed; nested exception is java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to com.realgrid.productControl.model.OrderDetails] with root cause 
java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to com.realgrid.productControl.model.OrderDetails 
    at com.realgrid.productControl.controller.ProductControlController.addOdMaster(ProductControlController.java:181) 
    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.invoke(InvocableHandlerMethod.java:213) 
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:126) 
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:96) 
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:617) 
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:578) 
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80) 
    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:304) 
    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 org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240) 
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164) 
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462) 
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164) 
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100) 
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:562) 
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) 
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:395) 
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:250) 
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:188) 
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302) 
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) 
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) 
    at java.lang.Thread.run(Unknown Source) 

क्यों नहीं ?

Answer 1

वसंत के पुराने संस्करणों में, वसंत नहीं (या बल्कि नहीं होता) निर्धारित कर सकते हैं कि

@RequestBody List<OrderDetails> od 

OrderDetails और इसलिए जैक्सन (JSON deserialiser) की एक सामान्य प्रकार एक डिफ़ॉल्ट के रूप में LinkedHashMap का उपयोग होता था प्रकार। टाइप करें सुरक्षा आपके मामले में टूट जाएगी क्योंकि इस पूरे अनुरोध से इनवोकेशन हैंडलिंग (@RequestMapping विधि और इसके तर्क) प्रतिबिंब के माध्यम से किया जाता है।

समाधान उन संस्करणों के लिए अपने स्वयं के प्रकार

public class OrderDetailsList extends ArrayList<OrderDetails> {} 

बना सकते हैं और उपयोग करें कि एक पैरामीटर

@RequestBody OrderDetailsList od 

के रूप में (या वसंत 4. में नवीनीकृत)