How to make IntelliJ IDEA highlight the implemented methods of an interface - eclipse

In Eclipse, when I put the caret on an Interface a class is implementing, the methods are marked in the side bar by default (as small colored stripes). This way I can easily see the methods the class is implementing without having to go into the interface itself and check out what methods it contains
I haven't found anything similar in IntelliJ. Is this even possible somehow easily?
(As a side note, I use Kotlin when programming, but I assume that this feature is not found for Java either)

In Java, you can put the caret on the "implements" keyword and press Ctrl-Shift-F7 to highlight methods implemented via an interface (if the class implements multiple interfaces, you get a popup asking you which methods to highlight). An equivalent feature for Kotlin is not implemented at this time (as of Kotlin 1.3).
In the class body, you can indeed see the interface methods highlighted by gutter icons, as the other answer says.

Methods or properties that are overriding or implementing anything of a parent class or interface are marked next to the line numbers, finding out from which class or interface they are coming can be done by hovering over them:
Clicking on it will take you to the parent/interface definition.
The same mark, but with a downwards pointing arrow, is used in the interface/parent class and shows a list of implementations/overrides when clicked on.
All of this also works for java and scala.

Related

adding icons to custom Eclipse editor hovers

I've created my own extension to DefaultTextHover within my custom Eclipse editor, and wanted to add icons to the hover -- similar to what the JDT does when I hover over a program element.
Currently, my implementation of getHoverInfo returns the appropriate String for the hover itself. But I would like the hover to also contain an icon -- similar to what I'm already using in my editor's outline.
How can I do this?
You need to make your extension to DefaultTextHover implement ITextHoverExtension which adds the new method getHoverControlCreator. This method returns a IInformationControlCreator which is used to create the IInformationControl which is used to display the hover information.
IInformationControl creates the hover and can interpret the hover text any way it wishes (as HTML for example).
There is a DefaultInformationControl implementation of IInformationControl available which does a lot of the work for you. This requires you to provide a class implementing DefaultInformationControl.IInformationPresenter and DefaultInformationControl.IInformationPresenterExtension.
There is an internal JFace class HTMLTextPresenter which can be used as an example for implementing the information presenter (since this is internal you should not use it directly).

Using an EditorPart inside a Composite

I'm new to RCP and I'm trying to create a new View or Editor. At the current state I'm extending ViewPart.
The Layout I want to achieve is a SashForm where both sides have a CTabFolder. One of the sides of the SashForm is basically a MultiPageEditorPart. One of it's tabs should be an editor for a specific language with syntax highlighting and similar features. From what I understand I could extend AbstractTextEditor for that (and maybe use it as one tab of a MultiPageEditorPart).
If I try to achieve this layout with a ViewPart as top level container which contains a SashForm, I can't add an EditorPart to one of the sides of the SashForm. Of course I could implement this editor from scratch as Composite but I want to avoid that.
I am also willing to use an EditorPart or MultiPageEditorPart as top level container but then I'd have to find a way to get the SashForm layout working. The whole editor should be splited first and then each side should have tabs.
Does anyone have an idea how to solve this?
If anything is unclear please ask. I've got the feeling I've put this into words a little complicatedly.
I think you should just make a ViewPart that has a text editing component of some kind on the left, instead of trying to find a way to use an EditorPart. All that EditorPart is really buying you is dirty flag management and Save support; syntax highlight and so forth you can add to the text editing component yourself (I was surprised at how few drop-in text components I found while poking around the internet just now; I expected to find "a few" and instead I found "basically none").
You can see one way to do very rudimentary syntax highlighting with a StyledText component here: JavaSourceCodeViewer
To see a more robust implementation of things like syntax highlight and autocomplete, take a look at the class that Eclipse uses for the editing of Java source code: CompilationUnitEditor
I think what you are trying to achieve is quite complicated and might require a lot of extra work. See an editor is not just different controls laid out in some order, but it has a lot of additional features that any editor class expects to work. These include things like selection service and action bars etc, that you will need to hook in to ensure smooth running.
That said, it should be possible to achieve what you are hoping for. You can have a look at the source code of the MultiPageEditorPart itself to see how it converts a single editor into a multi page editor, which is capable of hosting a completely independent editor on each of its pages. You would need to achieve something similar if you want your editor to host two MultiPageEditorParts separated by a sash. If you want to carry on, you should start implementing some stuff and if you run into any problems, post them here. You would be able to get a lot better help then.
You need something like MultiPageEditorSite. Use it for inspiration when implementing an EditorSiteDelegate. MultiPageEditorSite has support for separate keybindings between the pages, for example.
class ChildEditorSite implements IEditorSite {
IEditorSite parent;
public Object method() {
return parent.method();
}
}
Using this class, you can easily do the following in your main EditorPart:
class MyCoolPart extends EditorPart {
public void createControl(Composite parent) {
EditorPart child1 = new MyChild();
child1.init(new ChildEditorSite(getEditorSite()), myInput);
EditorPart child2 = new MyChild();
child2.init(new ChildEditorSite(getEditorSite()), myInput);
child1.createPartControl(parent);
child2.createPartControl(parent);
}
}
Be sure to also dispose of your children correctly when you dispose of your MyCoolPart. Please note that this only works in the most basic of cases. An EditorPart that is a DocumentEditor or that relies on IPersistablePart or implements listeners/adapters for confirming a save is probably going to require a lot more Lifecycle management...

How to implement Quick Fix / Quick Assist for custom eclipse editor?

I have extended org.eclipse.ui.editors.text.TextEditor to implement a custom editor.
For this editor, I have defined a marker type (org.eclipse.core.resources.markers extension point) and an annotation type (org.eclipse.ui.editors.annotationTypes extension point) to mark specific parts of code in my editor. I use a reconciler to update my annotation model.
Now I want to add a quick fix / quick assist feature. I simply want eclipse, to show a box with proposals, when I hover over an annotated part of the code and replace that part with a given string, when I click on a proposal. Just like the quick fix feature for the java editor.
So, what is the best way to implement this behavior?
I read about marker resolution generators and quick assist processors, but I'm still confused how it all works together...
I would be glad, if someone could point me to the right direction.
EDIT: From what I've understood so far, a MarkerResolutionGenerator is responsible for showing quick fixes in the problems view. To get quick fixes in the source viewer, I would have to set a QuickAssistAssistant for my SourceViewer and implement a QuickAssistProcessor which returns CompletionProposals.
Is this the right way to do it?
EDIT2: I'm wondering if I need Markers at all, or only Annotations, I'm confused...
I finally found out how to get Quick Fix to work for my editor.
I use the annotationTypes extension point to register my own annotation type and the markerAnnotationSpecification extension point to specify the look and feel. In my custom SourceViewerConfiguration class I override getAnnotationHover(...) to return a DefaultAnnotationHover object and getTextHover(...) to return a DefaultTextHover object, so the annotations are shown in my source viewer.
Then I override getReconciler(...) to return a MonoReconciler with my own implementation of IReconcilingStrategy to create the annotations in its reconcile(...) method. And finally I override getQuickAssistAssistant(...) to return a QuickAssistAssistant with my own implementation of IQuickAssistProcessor. The computeQuickAssistProposals(...) method in the processor class computes the quick fix proposals which show up, when I press CTRL+1.
I don't create any Marker objects and don't use a MarkerResolutionGenerator, since the marker concept is much more heavyweight than using only annotations and the functionality which annotations provide fits my needs.
You have to register an extension to the extension point org.eclipse.ui.ide.markerResolution. This extension refers to a markerType (using the markerId), and also a resolution generator.
The latter component is responsible for calculating the possible fixes: it reads the marker, it can check the related files, etc., and creates marker resolution instances. These resolution instances basically process the erroneous files, and hopefully fix the original problem.
During marker resolution, you should not worry about removing the markers, as after the fix is executed, sometimes the validation would run again (e.g. during the build, or if no automatic validation is available, then manually - but it is not the task of the marker resolution to update the list of markers).

GWT use of interface instead of widget

in a définition of a widget, what is a better practice, and why, use the widget himself or the type "higher", example, it's a better practice to do
1) Button myButton;
or
2) Hastext myButton; (and set a button later)
thanks for your answer.
It is usually a good idea to use "higher" types or interfaces. By doing this properly you can hide implementation details. The code that uses an object looks at it as the one of a higher type and it is not important what is actually hiding behind it. This is good because you can easily change an implementation of the object without breaking anything.
For example when defining a panel in an application you should use Panel class instead of its implementation e.g. HorizontalPanel or VerticalPanel.:
Panel myPanel;
Then you can create a proper implementation of it, e.g HorizontalPanel:
myPanel = new HorizontalPanel();
If you then later decide to change myPanel to be VerticalPanel you will not have to change anything in the code that uses myPanel. Everything will work just fine.
However you must remember that you will be only able to use methods available in Panel class. Additional methods defined in e.g. HorizontalPanel will not be accessible. And this is actually what you should remember when choosing the type of your widgets. Your widgets should be of types which provide methods which you want to use.
In your example using HasText instead of Button isn't probably a good idea because HasText has only methods for setting and getting a text and you probably also want to have access to addClickHandler method available in Button and a few more.
So to summarize it is good to use "higher types" but they should not be "too high" to be useful.
The answer to that lies in the Model-View-Presenter pattern, that was introduced in last years Google IO presentation by Ray Ryan. There's also an official tutorial/docs - part 1 and part 2. There are also a number of questions here on SO that cover that topic :)
And a quick answer to your question (that will make more sense once you get familiar with MVP): use interfaces in the Presenter and their implementations in the View :) That way your Presenter stays oblivious to the underlying implementation/Widget you actually used (was it a Button? Or a Label? It doesn't matter, they both implement HasText).

Adding Content to a GWT Horizontal Panel from another class

I am trying to populate the right-hand-side of a HorizontalPanel used in an onModuleLoad() method from another class (containing other widgets) so to keep the code separate.
What I am trying to achieve is similar to a PHP include where I can alter the code in another class and it will affect the right-hand panel only.
Does this other class have to be a composite widget? Or can I do a similar thing that I do when creating the Entry class?
I'm not sure if you mean you want to load a complete different GWT module on the right-hand panel or simply want to load a different class. I assume the latter.sense.
In such case a GWT TabPanel, but positioned Vertical. This is a combination of a DeckPanel and a TabBarPanel. In GWT there is standard VerticalTabPanel available, but you can find one in the open source cobogw library, see http://www.cobogw.org. An example including source code can be found on the demo page: http://cobogw.googlecode.com/svn/demo/WidgetsDemo.html#VerticalTabPanel
The example also uses a LazyPanel. This means each class is initialized only when the user clicks on the link, which makes startup a lot faster.
Just add the reference to the horizontalpanel to some other class (like a controller class or main panel class) and then call into this class from your right side panel. You can even have a controller class that holds this static horizontalpanel with a method like
HorizontalPanel hPanel; //set this from on module load, or controller.create method for instance
public static setRightContents(Panel panel){
hPanel.add(panel)
}
and just call this from the other class Controller.setRightContents(myNewRightPanel).
Really you just need to stop thinking this is a website and start thinking more of a thick client application using even driven programming.