javax.xml.bind.JAXBException: Class *** nor any of its super class is known to this context

Question

I'm trying to pass a object via REST web service. Following are my classes explains the functionality that I need using some example codes.

Rest Web Service Class method

@POST @Path("/find") @Consumes(MediaType.APPLICATION_FORM_URLENCODED) @Produces({MediaType.APPLICATION_JSON}) public Response getDepartments(){     Response response = new Response();      try {          response.setCode(MessageCode.SUCCESS);         response.setMessage("Department Names");         Department dept = new Department("12", "Financial");         response.setPayload(dept);      } catch (Exception e) {         response.setCode(MessageCode.ERROR);         response.setMessage(e.getMessage());         e.printStackTrace();     }            return response; } 

Response Class

import java.io.Serializable; import javax.xml.bind.annotation.XmlRootElement;  @XmlRootElement  public class Response implements Serializable{      private static final long serialVersionUID = 1L;      public enum MessageCode {         SUCCESS, ERROR, UNKNOWN     }      private MessageCode code;     private String message;     private Object payload;      public MessageCode getCode() {         return code;     }      public void setCode(MessageCode code) {         this.code = code;     }      public String getMessage() {         return message;     }      public void setMessage(String message) {         this.message = message;     }      public Object getPayload() {         return payload;     }      public void setPayload(Object payload) {         this.payload = payload;     } } 

Department Class

@XmlRootElement public class Department implements java.io.Serializable {       private String deptNo;     private String deptName;       public Department() {     }      public Department(String deptNo, String deptName) {         this.deptNo = deptNo;         this.deptName = deptName;     }      public String getDeptNo() {         return this.deptNo;     }      public void setDeptNo(String deptNo) {         this.deptNo = deptNo;     }      public String getDeptName() {         return this.deptName;     }      public void setDeptName(String deptName) {         this.deptName = deptName;     }  } 

When I make a call to getDepartments method in the rest web service class it returns following exceptions. But If I change the type Object of the payload to Department in the Response class it returns the json response correctly. But since I need to use this Response class for different types of Classes I can't restring the payload to one class type. Can anyone please help me in this matter?

Stack Trace

Dec 27, 2012 9:34:18 PM com.sun.jersey.spi.container.ContainerResponse logException SEVERE: Mapped exception to response: 500 (Internal Server Error) javax.ws.rs.WebApplicationException: javax.xml.bind.MarshalException  - with linked exception: [javax.xml.bind.JAXBException: class Department nor any of its super class is known to this context.]     at com.sun.jersey.core.provider.jaxb.AbstractRootElementProvider.writeTo(AbstractRootElementProvider.java:159)     at com.sun.jersey.spi.container.ContainerResponse.write(ContainerResponse.java:306)     at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1437)     at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1349)     at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1339)     at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416)     at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:537)     at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:699)     at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)     at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)     at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:401)     at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)     at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)     at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:766)     at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)     at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)     at org.mortbay.jetty.Server.handle(Server.java:326)     at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)     at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:945)     at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:756)     at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)     at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)     at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)     at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582) Caused by: javax.xml.bind.MarshalException  - with linked exception: [javax.xml.bind.JAXBException: class Department nor any of its super class is known to this context.]     at com.sun.xml.bind.v2.runtime.MarshallerImpl.write(MarshallerImpl.java:323)     at com.sun.xml.bind.v2.runtime.MarshallerImpl.marshal(MarshallerImpl.java:177)     at com.sun.jersey.json.impl.BaseJSONMarshaller.marshallToJSON(BaseJSONMarshaller.java:103)     at com.sun.jersey.json.impl.provider.entity.JSONRootElementProvider.writeTo(JSONRootElementProvider.java:136)     at com.sun.jersey.core.provider.jaxb.AbstractRootElementProvider.writeTo(AbstractRootElementProvider.java:157)     ... 23 more Caused by: javax.xml.bind.JAXBException: class Department nor any of its super class is known to this context.     at com.sun.xml.bind.v2.runtime.XMLSerializer.reportError(XMLSerializer.java:250)     at com.sun.xml.bind.v2.runtime.XMLSerializer.reportError(XMLSerializer.java:265)     at com.sun.xml.bind.v2.runtime.XMLSerializer.childAsXsiType(XMLSerializer.java:657)     at com.sun.xml.bind.v2.runtime.property.SingleElementNodeProperty.serializeBody(SingleElementNodeProperty.java:156)     at com.sun.xml.bind.v2.runtime.ClassBeanInfoImpl.serializeBody(ClassBeanInfoImpl.java:344)     at com.sun.xml.bind.v2.runtime.XMLSerializer.childAsSoleContent(XMLSerializer.java:597)     at com.sun.xml.bind.v2.runtime.ClassBeanInfoImpl.serializeRoot(ClassBeanInfoImpl.java:328)     at com.sun.xml.bind.v2.runtime.XMLSerializer.childAsRoot(XMLSerializer.java:498)     at com.sun.xml.bind.v2.runtime.MarshallerImpl.write(MarshallerImpl.java:320)     ... 27 more Caused by: javax.xml.bind.JAXBException: class Department nor any of its super class is known to this context.     at com.sun.xml.bind.v2.runtime.JAXBContextImpl.getBeanInfo(JAXBContextImpl.java:611)     at com.sun.xml.bind.v2.runtime.XMLSerializer.childAsXsiType(XMLSerializer.java:652)     ... 33 more 

Answer 1

JAX-RS implementations automatically support marshalling/unmarshalling of classes based on discoverable JAXB annotations, but because your payload is declared as Object, I think the created JAXBContext misses the Department class and when it's time to marshall it it doesn't know how.

A quick and dirty fix would be to add a XmlSeeAlso annotation to your response class:

@XmlRootElement @XmlSeeAlso({Department.class}) public class Response implements Serializable {   .... 

or something a little more complicated would be "to enrich" the JAXB context for the Response class by using a ContextResolver:

import javax.ws.rs.Produces; import javax.ws.rs.core.MediaType; import javax.ws.rs.ext.ContextResolver; import javax.ws.rs.ext.Provider; import javax.xml.bind.JAXBContext; import javax.xml.bind.JAXBException;  @Provider @Produces({ MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML }) public class ResponseResolver implements ContextResolver<JAXBContext> {     private JAXBContext ctx;      public ResponseResolver() {         try {             this.ctx = JAXBContext.newInstance(                          Response.class,                          Department.class                      );         } catch (JAXBException ex) {             throw new RuntimeException(ex);         }     }      public JAXBContext getContext(Class<?> type) {         return (type.equals(Response.class) ? ctx : null);     } } 

Answer 2

I have the same problem and I solved it by adding package to explore to the Jaxb2marshaller. For spring will be define a bean like this:

@Bean     public Jaxb2Marshaller marshaller() {         Jaxb2Marshaller marshaller = new Jaxb2Marshaller();         String[] packagesToScan= {"<packcge which contain the department class>"};         marshaller.setPackagesToScan(packagesToScan);         return marshaller;     } 

By this way if all your request and response classes are in the same package you do not need to specifically indicate the classes on the JAXBcontext