I'm trying to use JDT SearchEngine to find references to a given object. But I'm getting a "NullPointerException" while invoking the "search" method of org.eclipse.jdt.core.search.SearchEngine.
Following is the error trace:
java.lang.NullPointerException at
org.eclipse.jdt.internal.core.search.BasicSearchEngine.findMatches(BasicSearchEngine.java:214)
at
org.eclipse.jdt.internal.core.search.BasicSearchEngine.search(BasicSearchEngine.java:515)
at
org.eclipse.jdt.core.search.SearchEngine.search(SearchEngine.java:582)
And following is the method I'm using to perform search:
private static void search(String elementName) { //elementName -> a method Name
try {
SearchPattern pattern = SearchPattern.createPattern(elementName, IJavaSearchConstants.METHOD,
IJavaSearchConstants.REFERENCES, SearchPattern.R_PATTERN_MATCH);
IJavaSearchScope scope = SearchEngine.createWorkspaceScope();
SearchRequestor requestor = new SearchRequestor() {
#Override
public void acceptSearchMatch(SearchMatch match) {
System.out.println("Element - " + match.getElement());
}
};
SearchEngine searchEngine = new SearchEngine();
SearchParticipant[] searchParticipants = new SearchParticipant[] { SearchEngine
.getDefaultSearchParticipant() };
searchEngine.search(pattern, searchParticipants, scope, requestor, null);
} catch (Exception e) {
e.printStackTrace();
}
}
Refer the "Variables" window of the following snapshot to check the values of the arguments passing to the "searchEngine.search()":
I think the the issue is because of the value of "scope" [Highlighted in 'BLACK' above].
Which means "SearchEngine.createWorkspaceScope()" doesn't return expected values in this case.
NOTE: Please note that this is a part of my program which runs as a stand-alone java program (not an eclipse plugin) using JDT APIs to parse a given source code (using JDT-AST).
Isn't it possible to use JDT SearchEngine in such case (non eclipse plugin program), or is this issue due to some other reason?
Really appreciate your answer on this.
No. You cannot use the search engine without openning a workspace. The reason is that the SearchEngine relies on the eclipse filesystem abstraction (IResource, IFile, IFolder, etc.). This is only available when the workspace is open.
Related
I would like to send a binary file via an appended MVCResourceCommand I coded for the native journal portlet. But the program is unable to use the OutputStream provided by the resource request.
IOUtils.copy( input, response.getPortletOutputStream() );
Considering:
The code works perfectly on StrutsActions
In custom portlets, it also works
In StrutsActions:
IOUtils.copy( input, response.getOutputStream() );
However, the code throws an IllegalStateException, saying that the writer is being used when I call response.getOutputStream().
I know we can not mix these two
The code is not attempting to do so
I wonder if Liferay is doing something with that request before it reaches my extension of BaseMVCResourceCommand, this is specifically for that native portlet.
I checked the preview feature for a webcontect item, but its URL is for the view mode.
The URL is created from a portlet:resourceURL tag inserted through a JSP fragment and the command is in its own OSGi module.
For sure, the URL is correct and the command logs that it was hit, but the exception is thrown afterwards.
The portlet I am trying to change is the:
"com_liferay_journal_web_portlet_JournalPortlet"
Any thoughts?
PS: I know about the Servlet and Portlet ResponseUtils. but they also eventually try getting the stream, leadin to the same exception.
#Component( immediate = true,
property = {
"javax.portlet.name=" + JOURNAL, "mvc.command.name=/command"
},
service = MVCResourceCommand.class )
public class Resource extends BaseMVCResourceCommand {
#Override
public void doServeResource( ResourceRequest request, ResourceResponse response ) throws PortletException {
try {
response.getPortletOutputStream();
}
catch ( Exception e ) {
throw new PortletException( e );
}
}
}
Caused by: java.lang.IllegalStateException: Unable to obtain OutputStream because Writer is already in use
at com.liferay.portlet.MimeResponseImpl.getPortletOutputStream(MimeResponseImpl.java:75)
Update:
It seems this is the source of my issues (PortletURLImpl), still looking for a solution though:
if (lifecycle.equals(PortletRequest.RESOURCE_PHASE)) {
_copyCurrentRenderParameters = true;
}
When the URL is created it comes with all sources of garbage from the render phase. Including an MVCPath
In our poc, we have a cache in PARTIONED MODE, with 2 backups, and we started 3 nodes. 100 entries were loaded into cache and we did below steps to retrive it.
public void perform () throws GridException {
final GridCache<Long, Entity> cache= g.cache("cache");
GridProjection proj= g.forCache("cache");
Collection< Collection<Entity>> list= proj .compute().broadcast(
new GridCallable< Collection<Entity>>() {
#Override public Collection<Entity> call() throws Exception {
Collection<Entity> values= cache.primaryValues();
System.out.println("List size on each Node: "+ values.size());
// console from each node shows 28,38,34 respectively, which is correct
return values;
}
}).get();
for (Collection<Entity> e: list){
System.out.println("list size when arrives on main Node :"+ e.size());
//console shows 28 for three times, which is not correct
}
}
I assume that primaryValues() is to take value of each element returned by primaryEntrySet() out and put into a Collection. I also tried to use primaryEntrySet and it works without such problem.
The way GridGain serializes cache collections is by reference which may not be very intuitive. I have filed a Jira issue with Apache Ignite project (which is the next version of GridGain open source edition): https://issues.apache.org/jira/browse/IGNITE-38
In the mean time, please try the following from your GridCallable, which should work:
return new ArrayList(cache.primaryValues());
I am using Breeze with much success in my SPA, but seem to be stuck when trying to return parent->child data in a single query by using expand().
When doing a single table query, the $type in the JSON return is correct:
$type: MySPA.Models.Challenge, MySPA
However if I use expand() in my query I get the relational data, but the $type is this:
System.Collections.Generic.Dictionary 2[[System.String, mscorlib],[System.Object, mscorlib]]
Because of the $type is not the proper table + namespace, the client side code can't tell that this is an entity and exposes it as JSON and not a Breeze object (with observables, entityAspect, etc.).
At first I was using my own ContextProvider so that I could override the Before/After saving methods. When I had these problems, I reverted back to the stock EFContextProvider<>.
I am using EF5 in a database first mode.
Here's my controller code:
[BreezeController]
public class DataController : ApiController
{
// readonly ModelProvider _contextProvider = new ModelProvider();
readonly EFContextProvider<TestEntities> _contextProvider = new EFContextProvider<TestEntities>();
[HttpGet]
public string Metadata()
{
return _contextProvider.Metadata();
}
[Queryable(AllowedQueryOptions = AllowedQueryOptions.All)]
[HttpGet]
public IQueryable<Challenge> Challenges()
{
return _contextProvider.Context.Challenges;
}
[HttpPost]
public SaveResult SaveChanges(JObject saveBundle)
{
return _contextProvider.SaveChanges(saveBundle);
}
public IQueryable<ChallengeNote> ChallengeNotes()
{
return _contextProvider.Context.ChallengeNotes;
}
}
Here's my BreezeWebApiConfig.cs
public static void RegisterBreezePreStart()
{
GlobalConfiguration.Configuration.Formatters.Remove(GlobalConfiguration.Configuration.Formatters.XmlFormatter);
GlobalConfiguration.Configuration.Routes.MapHttpRoute(
name: "BreezeApi",
routeTemplate: "breeze/{controller}/{action}"
);
}
Is there a configuration setting that I am missing?
Did you try "expanding" on server side? Is it needed to do expand on client side? I tried to do expand before but failed for me as well, did some research and decided I'd rather place it on server:
[HttpGet]
public IQueryable<Challenge> ChallengesWithNotes()
{
return _contextProvider.Context.Challenges.Include("ChallengeNotes");
}
This should be parsed as expected. On client side you would query for "ChallengeNotes" instead of "Challenges" and you wouldn't need to write expand part.
I strongly suspect that the problem is due to your use of the [Queryable] attribute.
You must use the [BreezeQueryable] attribute instead!
See the documentation on limiting queries.
We are aware that Web API's QueryableAttribute has been deprecated in favor of EnableQueryAttribute in Web API v.1.5. Please stick with BreezeQueryable until we've had a chance to write a corresponding derived attribute for EnableQuery. Check with the documentation for the status of this development.
I tried making a form in GXT to upload files, but I see more examples on the net, I failed to make it work a simple FileUploadField to save the file locally.
Cde fragment:
formPanel = new FormPanel();
formPanel.setBodyBorder(false);
formPanel.setHeaderVisible(false);
formPanel.setAction(GWT.getModuleBaseURL() + "fileUpload");
formPanel.setEncoding(Encoding.MULTIPART);
formPanel.setMethod(Method.POST);
formPanel.setButtonAlign(HorizontalAlignment.CENTER);
formPanel.setHeaderVisible(true);
fileUploadField = new FileUploadField();
fileUploadField.setName("fileName");
fileUploadField.setAllowBlank(false);
fileUploadField.setFieldLabel("Archivo");
fileUploadField.addListener(Events.OnChange, new Listener<BaseEvent>() {
public void handleEvent(BaseEvent BaseEvent) {
aSubmitButton.setEnabled(true);
}
});
aSubmitButton = new Button("OK");
aSubmitButton.setEnabled(false);
aSubmitButton.setId("submit_button");
aSubmitButton.addSelectionListener(new SelectionListener<ButtonEvent>() {
#Override
public void componentSelected(ButtonEvent inButtonEvent) {
formPanel.submit();
}
});
The above code is the declaration of FormPanel and FileUploadField.
We use gwtupload-0.6.3-compat.jar library to do the job.
Basically, the idea is that on the server side you need to create a servlet, which is going to be accepting your uploaded files. The mentioned library provides UploadAction servlet extension facilitating that.
On the client side you can use one of gwtupload components. We use MultiUploader for instance. That's literally a few lines of code there. Main code is in the listener:
private IUploader.OnFinishUploaderHandler onFinishUploaderHandler = new IUploader.OnFinishUploaderHandler() {
public void onFinish(IUploader uploader) {
if (uploader.getStatus() == Status.SUCCESS) {
// What you want to do when file is uploaded.
}
}
};
The rest is taken care of by the component. Since the library is for GWT, it comes with source code, so you can see what it's doing behind the scene and read extensive comments in the code.
Free to use of course.
I have been trying to follow this example (download the source code from a link on the site or here, but I keep running into an error that seems embedded in the example.
My procedure has been as follows (after installing the AppFabric SDK and other dependencies):
Download the source
Create a Service Namespace on the AppFabric.
Import the project into a new Windows Azure project with one Worker Role, make sure that it all compiles and that the default Worker Role Run() method starts and functions.
Configure the method GetInterRoleCommunicationEndpoint in InterRoleCommunicationExtension.cs with the ServiceNameSpace and IssuerSecret from my AppFabric Service Namespace (IssuerName and ServicePath stay default). This is a hard-wiring of my own parameters.
Copy/paste the initialization logic from the "SampleWorkerRole.cs" file in the demo into the OnStart() method of my project's Worker Role
Comment-out references to Tracemanager.* as the demo code does not have the Tracemanager methods implemented and they're not crucial for this test to work. There are about 7-10 of these references (just do a Find -> "Tracemanager" in entire solution).
Build successfully.
Run on local Compute Emulator.
When I run this test, during the initialization of a new InterRoleCommunicationExtension (the first piece of the inter-role communication infrastructure to be initialized, this.interRoleCommunicator = new InterRoleCommunicationExtension();), an error is raised: "Value cannot be null. Parameter name: contractType."
Drilling into this a bit, I follow the execution down to the following method in ServiceBusHostFactory.cs (one of the files from the sample):public static Type GetServiceContract(Type serviceType)
{
Guard.ArgumentNotNull(serviceType, "serviceType");
Type[] serviceInterfaces = serviceType.GetInterfaces();
if (serviceInterfaces != null && serviceInterfaces.Length > 0)
{
foreach (Type serviceInterface in serviceInterfaces)
{
ServiceContractAttribute serviceContractAttr = FrameworkUtility.GetDeclarativeAttribute<ServiceContractAttribute>(serviceInterface);
if (serviceContractAttr != null)
{
return serviceInterface;
}
}
}
return null;
}
The serviceType parameter's Name property is "IInterRoleCommunicationServiceContract," which is one of the classes of the demo, and which extends IObservable. The call to serviceType.GetInterfaces() returns the "System.IObservable`1" interface, which is then passed into FrameworkUtility.GetDeclarativeAttribute(serviceInterface);, which has the following code:
public static IList GetDeclarativeAttributes(Type type) where T : class
{
Guard.ArgumentNotNull(type, "type");
object[] customAttributes = type.GetCustomAttributes(typeof(T), true);
IList<T> attributes = new List<T>();
if (customAttributes != null && customAttributes.Length > 0)
{
foreach (object customAttr in customAttributes)
{
if (customAttr.GetType() == typeof(T))
{
attributes.Add(customAttr as T);
}
}
}
else
{
Type[] interfaces = type.GetInterfaces();
if (interfaces != null && interfaces.Length > 0)
{
foreach (object[] customAttrs in interfaces.Select(iface => iface.GetCustomAttributes(typeof(T), false)))
{
if (customAttrs != null && customAttrs.Length > 0)
{
foreach (object customAttr in customAttrs)
{
attributes.Add(customAttr as T);
}
}
}
}
}
return attributes;
}</code><br>
It is here that the issue arises. After not finding any customAttributes on the "IObservable1" type, it calls type.GetInterfaces(), expecting a return. Even though type is "System.IObservable1," this method returns an empty array, which causes the function to return null and the exception with the above message to be raised.
I am extremely interested in getting this scenario working, as I think the Publish/Subscribe messaging paradigm is the perfect solution for my application. Has anyone been able to get this demo code (from the AppFabric CAT Team itself!) working, or can spot my error? Thank you for your help.
Answered in the original blog post (see link below). Please advise if you are still experiencing problems. We are committed to supporting our samples on best effort basis.
http://blogs.msdn.com/b/appfabriccat/archive/2010/09/30/implementing-reliable-inter-role-communication-using-windows-azure-appfabric-service-bus-observer-pattern-amp-parallel-linq.aspx#comments