I have embedded a GWT RPC call within onModuleLoad method and this RPC call does not seem to be executing the onSuccess method. Within the RPC implementation at the server side it works well with debug print statements.
Code snippet below,
public void onModuleLoad() {
System.out.println("ON MODULE LOAD");
mobiTeamService.login(GWT.getHostPageBaseURL(), new AsyncCallback<LoginInfo> () {
public void onFailure(Throwable error) { System.out.println("FAILURE"); ClientSideUtils.logError(mobiTeamService, CLS,error) ;}
public void onSuccess(LoginInfo result) {
System.out.println("ON SUCCESS: " + result) ;
loginInfo = result ;
}
}) ;
}
Ensure that you have done the below steps (GWT-RPC), if so then the onSuccess will be definitely executed.
Interface(MobiTeamService) should be extending RemoteService(com.google.gwt.user.client.rpc.RemoteService)
AsynInterface(MobiTeamServiceAsync) should be in the same package where your interface resides.
MobiTeamServiceImpl should be extending RemoteServiceServlet and implementing MobiTeamService interface
Map your MobiTeamServiceImpl servlet in the web.xml, a servlet entry and its mapping
If you have specific path for accessing the service, then the path defined on the interface(MobiTeamService) by tag RemoteServiceRelativePath should be matching with the url pattern entry in the web.xml
You can also go thru this tutorial to get more understanding on GWT-RPC
http://www.gwtproject.org/doc/latest/tutorial/RPC.html
Related
I have implementated a Rest web service (the function is not relevant) using JAX-RS. Now I want to generate its documentation using Swagger. I have followed these steps:
1) In build.gradle I get all the dependencies I need:
compile 'org.glassfish.jersey.media:jersey-media-moxy:2.13'
2) I documentate my code with Swagger annotations
3) I hook up Swagger in my Application subclass:
public class ApplicationConfig extends ResourceConfig {
/**
* Main constructor
* #param addressBook a provided address book
*/
public ApplicationConfig(final AddressBook addressBook) {
register(AddressBookService.class);
register(MOXyJsonProvider.class);
register(new AbstractBinder() {
#Override
protected void configure() {
bind(addressBook).to(AddressBook.class);
}
});
register(io.swagger.jaxrs.listing.ApiListingResource.class);
register(io.swagger.jaxrs.listing.SwaggerSerializers.class);
BeanConfig beanConfig = new BeanConfig();
beanConfig.setVersion("1.0.2");
beanConfig.setSchemes(new String[]{"http"});
beanConfig.setHost("localhost:8282");
beanConfig.setBasePath("/");
beanConfig.setResourcePackage("rest.addressbook");
beanConfig.setScan(true);
}
}
However, when going to my service in http://localhost:8282/swagger.json, I get this output.
You can check my public repo here.
It's times like this (when there is no real explanation for the problem) that I throw in an ExceptionMapper<Throwable>. Often with server related exceptions, there are no mappers to handle the exception, so it bubbles up to the container and we get a useless 500 status code and maybe some useless message from the server (as you are seeing from Grizzly).
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.Response;
import javax.ws.rs.ext.ExceptionMapper;
public class DebugMapper implements ExceptionMapper<Throwable> {
#Override
public Response toResponse(Throwable exception) {
exception.printStackTrace();
if (exception instanceof WebApplicationException) {
return ((WebApplicationException)exception).getResponse();
}
return Response.serverError().entity(exception.getMessage()).build();
}
}
Then just register with the application
public ApplicationConfig(final AddressBook addressBook) {
...
register(DebugMapper.class);
}
When you run the application again and try to hit the endpoint, you will now see a stacktrace with the cause of the exception
java.lang.NullPointerException
at io.swagger.jaxrs.listing.ApiListingResource.getListingJson(ApiListingResource.java:90)
If you look at the source code for ApiListingResource.java:90, you will see
Swagger swagger = (Swagger) context.getAttribute("swagger");
The only thing here that could cause the NPE is the context, which scrolling up will show you it's the ServletContext. Now here's the reason it's null. In order for there to even be a ServletContext, the app needs to be run in a Servlet environment. But look at your set up:
HttpServer server = GrizzlyHttpServerFactory
.createHttpServer(uri, new ApplicationConfig(ab));
This does not create a Servlet container. It only creates an HTTP server. You have the dependency required to create the Servlet container (jersey-container-grizzly2-servlet), but you just need to make use of it. So instead of the previous configuration, you should do
ServletContainer sc = new ServletContainer(new ApplicationConfig(ab));
HttpServer server = GrizzlyWebContainerFactory.create(uri, sc, null, null);
// you will need to catch IOException or add a throws clause
See the API for GrizzlyWebContainerFactory for other configuration options.
Now if you run it and hit the endpoint again, you will see the Swagger JSON. Do note that the response from the endpoint is only the JSON, it is not the documentation interface. For that you need to use the Swagger UI that can interpret the JSON.
Thanks for the MCVE project BTW.
Swagger fixed this issue in 1.5.7. It was Issue 1103, but the fix was rolled in last February. peeskillet's answer will still work, but so will OP's now.
I'm currently working on a simple GWT project. One of the things I'd like to do is that when the page loads I can dynamically populate the contents of a ListBox based on certain criteria. I actually don't see any handlers for a ListBox to handle the initial render event but I see change handlers.
How does one populate a ListBox contents with data from the server side on pageload with GWT?
Right now I have a class that implements EntryPoint that has a
final ListBox fooList = new ListBox();
I also have a set of beans but I also have a class implementing RemoteService. Since I can't seem to get direct calls to my user defined packages directly in the EntryPoint (which makes sense) how do I populate that ListBox with server side content on initial page load? Right now I'm using a List but I figure if I cant get that to work I can get a DB call to work...
I've tried things in the EntryPoint like:
for (String name : FOOS) {
fooList.addItem(name, name);
}
However FOOS would derive from a server side data and the EntryPoint is supposed to be largerly limited to what can compile to JS! I can't get user defined classes to be recognized on that side as that string is the result of a set of user defined classes.
I also tried creating a method in the class implementing RemoteService that returns a ListBox. This also didn't compile when I tried to call this method. Perhaps I don't fully understand how to call methods in a RemoteService service implementing class.
I've searched a lot and I can't find anything that clearly explains the fundamentals on this. My background is much more ASP.NET and JSPs so perhaps I'm missing something.
I'm using GWT 2.6 is that is relevant.
The usual procedure is the following:
Create a bean class for the data you want to transmit between client and server. Let's call it MyBean.
Place MyBean in the shared package of your project.
This class has to implement either Serializable or IsSerializable, otherwise GWT will complain that it doesn't know how to transmit it.
Create your RemoteService that contains the method you want to use to transmit MyBean from/to the server.
Once you get your data on the client using an AsyncCallback and your RemoteService, fill the ListBox using your beans, e.g. by calling MyBean#getName() or MyBean#toString().
Success!
I based my example on the GWT sample project ( I named it example), just replace the classes and it should work :
public class Example implements EntryPoint {
/**
* Create a remote service proxy to talk to the server-side Greeting
* service.
*/
private final GreetingServiceAsync greetingService = GWT
.create(GreetingService.class);
/**
* This is the entry point method.
*/
public void onModuleLoad() {
final ListBox listBox = new ListBox();
RootPanel.get("sendButtonContainer").add(listBox);
greetingService.getSomeEntries(new AsyncCallback<String[]>() {
#Override
public void onSuccess(String[] result) {
for (int i = 0; i < result.length; i++) {
listBox.addItem(result[i]);
}
}
#Override
public void onFailure(Throwable caught) {
}
});
}
}
This is our EntryPoint, it creates a listbox and calls the server with a AsyncCallback to get some dynamic data. If the call is successfull (onSuccess), the data is written into the listbox.
The GreetingService interface define the synchronous methods, it is implemented in the GreetingServiceImpl class :
#RemoteServiceRelativePath("greet")
public interface GreetingService extends RemoteService {
String[] getSomeEntries() ;
}
The asynchronous counterpart is the GreetingServiceAsync interface, we used it before to call the server :
public interface GreetingServiceAsync {
void getSomeEntries(AsyncCallback<String[]> callback) ;
}
The GreetingServiceImpl class is located on the server. Here you could call for example a database:
#SuppressWarnings("serial")
public class GreetingServiceImpl extends RemoteServiceServlet implements
GreetingService {
#Override
public String[] getSomeEntries() {
String[] entries = { "Entry 1","Entry 2","Entry 3" };
return entries;
}
}
Now if you want to use some Bean/Pojo between the server and client, replace the String[] in each class/interface with the object name, put the class in the shared package and consider that it implements Serializable/IsSerializable.
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 trying to implement an API (SCORM API) using GWT.
The client code expects an API object with methods like Initialize(), getLastError() and so on...
I tried to implement this api as an Java Object, but i see that the compiled names are changed and cannot be used directly by client code.
I see that gwt-exporter can do the trick (http://code.google.com/p/gwt-exporter/) but i would like to know how to do it using pure gwt and jsni.
As the API is expected as a object, named API_1484_11 attached to the window object, not an function, , i don't see how to use the $entry() idiom.
Here is my current, failing, code:
public final class SCORMApi {
protected SCORMApi() {}
public void Initialize(){
GWT.log("** INITIALIZE CALLED **");
}
public static void create(){
bind(new SCORMApi());
}
public static native void bind(SCORMApi api) /*-{
$wnd.API_1484_11 = api;
}-*/;
}
So, in this context, my question is:
How can i get javascript calls (e.g. window.API_1484_11.Initialize() ) to reach my java gwt code?
You're on the right lines with your bind method. But you haven't understood how to call Java methods from within JSNI. This is how you do it in the case of your Initialize method:
public static native void bind(SCORMApi api) /*-{
$wnd.API_1484_11 = {
initialize: function() {
$entry( api.#com.yourpackage.name.SCORMApi::Initialize()() );
}
};
}-*/;
The blogs Getting To Really Know GWT parts 1 and 2 are required reading on this subject.
I'm listening for a window close event:
closeHandlerReg = Window.addCloseHandler(new CloseHandler<Window>() {
#Override
public void onClose(CloseEvent<Window> event) {
// ...
}
});
The documentation says that no UI can be shown in that callback. What about GWT RPC calls? I'm trying to make one, but it isn't showing up on the server (either in breakpoints or log statements).
Problem is that GWT RPC is asynchronous and the calls to RPC services return immediately. In this case the window is closed before the browser has a chance to send the underlying XMLHTTPRequest.
If it's absolutely necessary you should be able to hand-craft calling some sort of servlet (not GWT RPC) with a "synchronous" XMLHTTPRequest. Have a look here for an example: http://weblogs.asp.net/bleroy/archive/2005/12/15/433278.aspx
But really you shouldn't be doing anything of this sort in the window.onunload or window.onbeforeunload (these are the underlying DOM events for CloseEvent and ClosingEvent for the Window. Perhaps there is a better way to do what you are trying to do.
The use case you have should be possible. When you make the RPC call in the closeHandler it should arrive at the server, because while it returns directly, it has started sending the data, and set a callback to wait for the result. However the callback will fail because the connection is lost because the window is closed. But that is no problem as you only want to notify the server. So the question might be what are you sending? and does it work at all, when you send it at some other point in the code, not in the closeHandler?
Old question, but still - maybe someone faces the same issue.
RPCs won't work in the closing handler as already discussed. This workaround worked for me:
In the onClose method, do something like:
Window.Location.replace(GWT.getModuleBaseURL() + "rpcCall?param1=" + param1 + "¶m2=" + param2);
whereas "rpcCall" is the name of the rpc url you have set in your web.xml file. Of course, a random number of parameters may be passed within the URL.
Then, in your server-side implementation of your rpc interface, you can override the doGet method:
#Override
public void doGet(HttpServletRequest request, HttpServletResponse response) {
String param1 = URLDecoder.decode(request.getParameter("param1"), "UTF-8");
String param2 = URLDecoder.decode(request.getParameter("param2"), "UTF-8");
// do something
}
And another solution: Don't do an rpc call on window closing, but a regular http call that can then be handled by a custom servlet on the server side.
In your GWT module, do something like this:
Window.addWindowClosingHandler(new ClosingHandler() {
#Override
public void onWindowClosing(ClosingEvent event) {
sendWindowClosed(GWT.getModuleBaseURL() + "teardownservice");
}
});
private native void sendWindowClosed(String url)
/*-{
var Http = new XMLHttpRequest();
Http.open("GET", url);
Http.send();
}-*/;
}
In the server-side servlet, you can then handle this call:
public class TearDownServlet extends HttpServlet {
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
.... whatever you want ....
}
}