I am wishing to serialize a complex object for returning from a web service request. Here are my assumptions. I need to have the serialized (deflated) object in an XML document (as opposed to a string) before returning to the calling client. I "believe" I am deserializing just fine it is just a matter of getting it loaded into the XMLDocument. However I could be wrong and the deserialization may be wrong therefore the XmlDocument blows up. Here is the code:
My Complex Object:
namespace ABCTest
{
[XmlRoot("TapRoot")]
public class UserDetails
{
[XmlElement]
public String AccountName { get; set; }
}
}
My serialization code:
FYi: UsrDtls == List<UserDetails>
XmlSerializer Obj2XML = new XmlSerializer(UsrDtls.GetType());
Stream strWriter = Stream.Null;
XmlWriter XWriter = new XmlTextWriter(strWriter, Encoding.Unicode);
XmlDocument XDoc = new XmlDocument();
Obj2XML.Serialize(XWriter, lst_Exercises);
string abc = Obj2XML.ToString(); //debugging line to attempt to browse the obj2xml object
XDoc.LoadXml(abc);
return XDoc;
I have no idea where you learned about web services in .NET. Just return the object. The web service infrastructure will take care of it.
You don't say whether you're using WCF services or the legacy ASMX services. The ASMX services should not be used for new development.
If you still have trouble when you "just return it", then please post the details of any exceptions you receive.
Related
currently I am coding on a mock for a rest service we're using. For one case I want to return a 404 with a specific message in the body:
#POST
#Produces(MediaType.APPLICATION_XML)
#Consumes(MediaType.APPLICATION_XML)
#Path("/bookings")
public javax.ws.rs.core.Response performBooking(final BookingRequest booking) {
if (shouldfail(booking)) {
return Response.status(Response.Status.NOT_FOUND).entity("specific message in entity").build();
}
// some more other cases below...
}
If I test the mock with a unit test everything works fine:
final String failedMessage = response.getEntity().toString();
But if I deploy the rest service and call it, I will get the correct 404 code, but the entity is null.
For valid answers I put a BookingResponse object in the entity (simple DTO with some IDs in it) and it works for that. Just the string seems to disappear.
Any idea why my string disappears?
This question already has answers here:
Need some advice for trying to mock a .NET WebClient or equivalent
(2 answers)
Closed 6 years ago.
Let's assumed that i've got simple method which gets some data from REST service. Method looks like:
public string GetDataFromRest(string uri) {
string result = String.Empty;
using(WebClient web = new WebClient()) {
result = web.DownloadString(uri);
}
return result;
}
So, now i want to create unit test for this method. I don't want to use external REST service but i want fake response from any URI without real conecting to service. Something like every execute of GetDataFromRest(uri) in Unit Test -> always returns some XML.
As the posted answer goes into some detail, part of your problem is you have a dependency on the WebClient class.
A sample wrapper for WebClient could look like:
public interface IWebClient
{
string DownloadString(string address);
}
public class WebClientWrapper : IWebClient
{
public string DownloadString(string address)
{
using(WebClient web = new WebClient()) {
return result = web.DownloadString(uri);
}
}
}
public class MyClass
{
private readonly IWebClient _webClient;
public MyClass(IWebClient webClient)
{
_webClient = webClient;
}
public string GetDataFromRest(string uri)
{
return _webClient.DownloadString(uri);
}
}
Now of course going this route means WebClientWrapper can be unit tested with a "less real" URI or what that you specifically control. I've only implemented one method of the WebClient, but this externalizes the dependency within GetDataFromRest from a real URI, as you can now mock the return data. This also helps in that anything else you need a WebClient for, you can now use the wrapper class, and easily mock the returned data, as you are now programming to an interface, rather than a concretion.
I am using Spring 4 + Jackson 2 and have written a fully functional POST method using #RequestBody on a custom class. This method has no trouble unmarshalling the object.
#ResponseBody
#RequestMapping(value="store", method = RequestMethod.POST)
public ServiceResponse store(#RequestBody CustomClass list) {
...
}
// Request: { code: "A", amount: 200 }
When I attempted to add another method to handle a collection of the same class instead, my POST requests were returning with the following error.
HTTP Status 400: The request sent by the client was syntactically incorrect.
I note that this error typically occurs when the JSON submitted does not match the entity class. However, all I am doing is submitting an array of the same object instead of the object itself, which has already proven to work.
#ResponseBody
#RequestMapping(value="store-bulk", method = RequestMethod.POST)
public ServiceResponse storeBulk(#RequestBody List<CustomClass> list) {
...
}
// Request: [{ code: "A", amount: 200 }, { code: "B", amount: 400 }]
Am I missing something here?
In Java, type information for generics is erased at runtime, so Spring sees your List<CustomClass> object as List<Object> object, thus it cannot understand how to parse it.
One of ways to solve it, you could capture the type information by creating a wrapper class for your list, like this:
public class CustomClassList extends ArrayList<CustomClass> {
}
Sergey is right that the issue is due to type erasure. Your easiest way out is to bind to an array, so
#ResponseBody
#RequestMapping(value="store-bulk", method = RequestMethod.POST)
public ServiceResponse storeBulk(#RequestBody CustomClass[] object) {
...
}
The answer is that Spring 4 doesn't actually get rid of type erasure, contrary to what some other solutions suggest. While experimenting on debugging via manual unmarshalling, I decided to just handle that step myself instead of an implicit cast that I have no control over. I do hope someone comes along and proves me wrong, demonstrating a more intuitive solution though.
#ResponseBody
#RequestMapping(value="store-bulk", method = RequestMethod.POST)
public ServiceResponse storeBulk(#RequestBody String json) {
try {
List<CustomClass> list = new ObjectMapper().readValue(json, new TypeReference<List<CustomClass>>() { });
...
} catch (Exception e) {
...
}
}
Bonus: Right after I got this working, I bumped into this exception:
IllegalStateException: Already had POJO for id
If anyone gets this, it's because the objects in the list happen to reference some object that another item in the list already references. I could work around this since that object was identical for my entire collection, so I just removed the reference from the JSON side from all but the first object. I then added the missing references back after the JSON was unmarshalled into the List object.
Two-liner for the Java 8 users (the User object reference was the issue in my case):
User user = list.get(0).getUser();
list.stream().filter(c -> c.getUser() == null).forEach(t -> t.setUser(user));
I am trying to implement REST Service using XPage REST Service Control. I have opted for "customRESTService".
I would like to emit JSON when this service is requested. I can write logic in Server Side Java Script.
But I noticed that this customRESTService also supports "serviceBean", meaning I can write whole logic in pure JAVA.
I have given below code of the bean. I have declared it in faces-config.xml as well. But it throws exception while rendering. Has anyone used "serviceBean" in customRESTService?
I appreciate any help!! Thanks!!
public class GetApproverJSON{
public GetApproverJSON(){
System.out.println("Instantiating Bean");
}
public String doGet() throws NotesException{
JSONObject mainObj = new JSONObject();;
JSONObject itemObj;
try{
mainObj.put("label", "name");
mainObj.put("identifier", "abbr");
itemObj = new JSONObject();
itemObj.put("name", "");
itemObj.put("abbr", "");
mainObj.accumulate("items", itemObj);
return mainObj.toString();
}catch(Exception e){
System.out.println("Exception occured while generating JSON ");
e.printStackTrace();
return mainObj.toString();
}finally{
}
}
Error :
com.ibm.domino.services.ServiceException: Error while rendering service
at com.ibm.xsp.extlib.component.rest.CustomService$ScriptServiceEngine.renderService(CustomService.java:304)
at com.ibm.domino.services.HttpServiceEngine.processRequest(HttpServiceEngine.java:167)
at com.ibm.xsp.extlib.component.rest.UIBaseRestService._processAjaxRequest(UIBaseRestService.java:252)
at com.ibm.xsp.extlib.component.rest.UIBaseRestService.processAjaxRequest(UIBaseRestService.java:229)
at com.ibm.xsp.util.AjaxUtilEx.renderAjaxPartialLifecycle(AjaxUtilEx.java:206)
at com.ibm.xsp.webapp.FacesServletEx.renderAjaxPartial(FacesServletEx.java:221)
at com.ibm.xsp.webapp.FacesServletEx.serviceView(FacesServletEx.java:166)
at com.ibm.xsp.webapp.FacesServlet.service(FacesServlet.java:160)
at com.ibm.xsp.webapp.FacesServletEx.service(FacesServletEx.java:137)
at com.ibm.xsp.webapp.DesignerFacesServlet.service(DesignerFacesServlet.java:103)
at com.ibm.designer.runtime.domino.adapter.ComponentModule.invokeServlet(ComponentModule.java:576)
at com.ibm.domino.xsp.module.nsf.NSFComponentModule.invokeServlet(NSFComponentModule.java:1267)
at com.ibm.designer.runtime.domino.adapter.ComponentModule$AdapterInvoker.invokeServlet(ComponentModule.java:847)
at com.ibm.designer.runtime.domino.adapter.ComponentModule$ServletInvoker.doService(ComponentModule.java:796)
at com.ibm.designer.runtime.domino.adapter.ComponentModule.doService(ComponentModule.java:565)
at com.ibm.domino.xsp.module.nsf.NSFComponentModule.doService(NSFComponentModule.java:1251)
at com.ibm.domino.xsp.module.nsf.NSFService.doServiceInternal(NSFService.java:598)
at com.ibm.domino.xsp.module.nsf.NSFService.doService(NSFService.java:421)
at com.ibm.designer.runtime.domino.adapter.LCDEnvironment.doService(LCDEnvironment.java:341)
at com.ibm.designer.runtime.domino.adapter.LCDEnvironment.service(LCDEnvironment.java:297)
at com.ibm.domino.xsp.bridge.http.engine.XspCmdManager.service(XspCmdManager.java:272)
Caused by: com.ibm.xsp.FacesExceptionEx: Bean getApproverJSON is not a CustomServiceBean
at com.ibm.xsp.extlib.component.rest.CustomService.findBeanInstance(CustomService.java:226)
at com.ibm.xsp.extlib.component.rest.CustomService$ScriptServiceEngine.renderService(CustomService.java:255)
... 20 more
You need to change your code to:
public class GetApproverJSON{ ...}
to:
public class GetApproverJSON extends CustomServiceBean {
#Override
public void renderService(CustomService service, RestServiceEngine engine) throws ServiceException {
HttpServletRequest request = engine.getHttpRequest();
HttpServletResponse response = engine.getHttpResponse();
response.setHeader("Content-Type", "application/json; charset=UTF-8");
// Here goes your code, get the response writer or stream
}
since that's the interface the REST service is expecting. You will need to implement just renderService. You can get the method (GET, POST etc.) from the request object
I've never used the service bean before, I usually create my own parser with a static doGet method very similar to yours and in the doGet property of the custom REST service make a call to the static doGet method I create. But I think (I'm probably wrong on this count) if you use the service bean it has to be an entire servlet like if you wrote your own actual REST Service, and not just the parser portion.
I've created quite a few of the parsers and have found that a list of maps:
List>
is usually the best approach for building the initial data. I then loop through the list to build my JSON. In the Extension Library there is a class called JsonWriter which makes it very easy to build a JSON Object. Use the JsonWriter like:
StringWriter sw = new StringWriter();
JsonWriter jw = new JsonWriter(sw);
jw.startObject();
jw.startProperty("SomeProperty");
jw.outStringLiteral("SomeValue");
jw.endProperty();
jw.endObject();
return sw.toString();
For a full on example you can take a look at the REST service I built for my JQuery FullCalendar demo. While none of the methods are static (I need to track a couple of properties) you should get the basic idea. But what kicks the whole thing off is a call to the writeJson() method. That is invoked in this custom control.
Those examples should get you going on building your own custom JSON parser and emitting that JSON back to your application.
I am using Jersey Framework for developing my Webservices. I have a DTO object named UserInfo with setters and getters inside it. I am setting this DTO value initially when the user logs in. How can I pass this user-specific DTO to a Jersey service class?
I have tried setting them inside MultivaluedMap and Form but I was out of luck making it work.
This is my code :
MultivaluedMap<String, String> queryParams = new MultivaluedMapImpl();
queryParams.add("queryTerm", "userdto");
Form f = new Form();
f.add("name", "1001D");
And this is the way I am trying to retrieve the Data.
public class HaiService {
#GET
#Produces("application/json")
#Consumes("application/json")
public String sayPlainTextHello(#Context UriInfo ui) {
MultivaluedMap queryParams=ui.getQueryParameters();
Iterator it=queryParams.keySet().iterator();
String theKey=null;
String returnString="";
while(it.hasNext()) {
theKey=(String)it.next();
System.out.println(queryParams.getFirst(theKey));
}
System.out.println("I am called");
return "Hi";
}
But I was out of luck. Typically my requirement is to store user-specific data on logon, and then retrive that inside the service class.
I am avoiding storing data in session because a user might login with multiple ID's under one browser, which produces the same session id, and there is a chance of data being overwritten for the first logged in user.