Eclipse CDT extend AdapterFactory - eclipse

I try to override the functionality of CDT ResumeAtLine, MoveToLine, RunToLine. For this reason I created a custom SuspendResumeAdapterFactory but it isn't loaded but compiles and runs without error. Do I maybe need a custom adaptableType too?
Here is the content of my plugin.xml.
<extension point="org.eclipse.core.runtime.adapters">
<factory
class="my.package.CustomSuspendResumeAdapterFactory"
adaptableType="org.eclipse.cdt.dsf.ui.viewmodel.IVMContext">
<adapter type="org.eclipse.debug.core.model.ISuspendResume"/>
</factory>
</extension>
And here my CustomSuspendResumeAdapterFactory this class is reconstructed from memory not 100% sure if the syntax is correct, but I think it should be clear to see what I want to do.
package my.package;
import org.eclipse.cdt.dsf.datamodel.DMContexts;
import org.eclipse.cdt.dsf.debug.internal.ui.actions.MoveToLine;
import org.eclipse.cdt.dsf.debug.internal.ui.actions.ResumeAtLine;
import org.eclipse.cdt.dsf.debug.internal.ui.actions.RunToLine;
import org.eclipse.cdt.dsf.debug.service.IRunControl.IContainerDMContext;
import org.eclipse.cdt.dsf.debug.service.IRunControl.IExecutionDMContext;
import org.eclipse.cdt.dsf.ui.viewmodel.datamodel.IDMVMContext;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.IAdapterFactory;
import org.eclipse.debug.core.DebugException;
import org.eclipse.debug.core.model.ISuspendResume;
public class CustomSuspendResumeAdapterFactory implements IAdapterFactory {
static class SuspendResume implements ISuspendResume, IAdaptable {
private final CustomRunToLine fRunToLine;
private final CustomMoveToLine fMoveToLine;
private final CustomResumeAtLine fResumeAtLine;
SuspendResume(IExecutionDMContext execCtx) {
fRunToLine = new CustomRunToLine(execCtx);
fMoveToLine = new CustomMoveToLine(execCtx);
fResumeAtLine = new CustomResumeAtLine(execCtx);
}
#SuppressWarnings("unchecked")
#Override
public <T> T getAdapter(Class<T> adapter) {
if (adapter.isInstance(RunToLine.class)) {
System.out.println("CUSTOM RUNTOLINE");
return (T)fRunToLine;
}
if (adapter.isInstance(MoveToLine.class)) {
System.out.println("CUSTOM MOVETOLINE");
return (T)fMoveToLine;
}
if (adapter.isInstance(ResumeToLine.class)) {
System.out.println("CUSTOM RESUMEATLINE");
return (T)fResumeAtLine;
}
return null;
}
#Override
public boolean canResume() { return false; }
#Override
public boolean canSuspend() { return false; }
// This must return true because the platform
// RunToLineActionDelegate will only enable the
// action if we are suspended
#Override
public boolean isSuspended() { return true; }
#Override
public void resume() throws DebugException {}
#Override
public void suspend() throws DebugException {}
}
#SuppressWarnings("unchecked")
#Override
public <T> T getAdapter(Object adaptableObject, Class<T> adapterType) {
if (ISuspendResume.class.equals(adapterType)) {
if (adaptableObject instanceof IDMVMContext) {
IExecutionDMContext execDmc = DMContexts.getAncestorOfType(
((IDMVMContext)adaptableObject).getDMContext(),
IExecutionDMContext.class);
// It only makes sense to RunToLine, MoveToLine or
// ResumeAtLine if we are dealing with a thread, not a container
if (execDmc != null && !(execDmc instanceof IContainerDMContext)) {
return (T)new SuspendResume(execDmc);
}
}
}
return null;
}
#Override
public Class<?>[] getAdapterList() {
return new Class[] { ISuspendResume.class };
}
}

Why your code is not run
You have provided a new adapter factory that converts object types that are already handled. i.e. your plugin.xml says you can convert IVMContext to ISuspendResume. But the DSF plug-in already provides such an adapter factory. If you have a new target type (like IMySpecialRunToLine) you could install a factory for that, it would take IVMContext and convert it to a IMySpecialRunToLine).
Although dated, the Eclipse Corner Article on Adapter Pattern may be useful if this is a new concept.
How to do custom Run To Line implementation
If you want to provide different implementation of Run To Line, you need to provide your own version of org.eclipse.cdt.dsf.debug.service.IRunControl2.runToLine(IExecutionDMContext, String, int, boolean, RequestMonitor). The org.eclipse.cdt.dsf.debug.internal.ui.actions.RunToLine class is simply glue to connect UI features (such as buttons/etc some provided directly, some by the core eclipse debug) to the DSF backend. i.e. if you look at what RunToLine does, all it actually does is get the IRunControl2 service and call runToLine on it.
The way to provider your own implementation of IRunControl2 is override org.eclipse.cdt.dsf.gdb.service.GdbDebugServicesFactory.createRunControlService(DsfSession) and provide your own GdbDebugServicesFactory in your custom launch delegate by overriding org.eclipse.cdt.dsf.gdb.launching.GdbLaunchDelegate.newServiceFactory(ILaunchConfiguration, String)
RunToLine will be triggered when the user select Run To Line from the popup menu in the editor, as per this screenshot:

Related

How to override installed mappings of Behavior?

In java-9 Skins made it into public scope, while Behaviors are left in the dark - nevertheless changed considerably, in now using InputMap for all input bindings.
CellBehaviorBase installs mouse bindings like:
InputMap.MouseMapping pressedMapping, releasedMapping;
addDefaultMapping(
pressedMapping = new InputMap.MouseMapping(MouseEvent.MOUSE_PRESSED, this::mousePressed),
releasedMapping = new InputMap.MouseMapping(MouseEvent.MOUSE_RELEASED, this::mouseReleased),
new InputMap.MouseMapping(MouseEvent.MOUSE_DRAGGED, this::mouseDragged)
);
A concrete XXSkin now installs the behavior privately:
final private BehaviorBase behavior;
public TableCellSkin(TableCell control) {
super(control);
behavior = new TableCellBehavior(control);
....
}
The requirement is replace the mousePressed behavior (in jdk9 context). The idea is to grab super's field reflectively, dispose all its mappings and install the custom behavior. For some reason that I don't understand, the old bindings are still active (though the old mappings are empty!) and are invoked before the new bindings.
Below is a runnable example to play with: the mapping to mousePressed is simply implemented to do nothing, particularly to not invoke super. To see the old bindings at work, I set a conditional debug breakpoint at CellBehaviorBase.mousePressed like (in Eclipse):
System.out.println("mousePressed super");
new RuntimeException("whoIsCalling: " + getNode().getClass()).printStackTrace();
return false;
Run a debug and click into any cell, then the output is:
mousePressed super
java.lang.RuntimeException: whoIsCalling: class de.swingempire.fx.scene.control.cell.TableCellBehaviorReplace$PlainCustomTableCell
at com.sun.javafx.scene.control.behavior.CellBehaviorBase.mousePressed(CellBehaviorBase.java:169)
at com.sun.javafx.scene.control.inputmap.InputMap.handle(InputMap.java:274)
at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
//... lots more of event dispatching
// until finally the output in my custom cell behavior
Feb. 02, 2016 3:14:02 NACHM. de.swingempire.fx.scene.control.cell.TableCellBehaviorReplace$PlainCustomTableCellBehavior mousePressed
INFORMATION: short-circuit super: Bulgarisch
I would expect to only see the very last part, that is the printout by my custom behavior. It feels like I'm somehow fundamentally off - but can't nail it. Ideas?
The runnable code (sorry for its length, most is boiler-plate, though):
public class TableCellBehaviorReplace extends Application {
private final ObservableList<Locale> locales =
FXCollections.observableArrayList(Locale.getAvailableLocales());
private Parent getContent() {
TableView<Locale> table = createLocaleTable();
BorderPane content = new BorderPane(table);
return content;
}
private TableView<Locale> createLocaleTable() {
TableView<Locale> table = new TableView<>(locales);
TableColumn<Locale, String> name = new TableColumn<>("Name");
name.setCellValueFactory(new PropertyValueFactory<>("displayName"));
name.setCellFactory(p -> new PlainCustomTableCell<>());
TableColumn<Locale, String> lang = new TableColumn<>("Language");
lang.setCellValueFactory(new PropertyValueFactory<>("displayLanguage"));
lang.setCellFactory(p -> new PlainCustomTableCell<>());
table.getColumns().addAll(name, lang);
return table;
}
/**
* Custom skin that installs custom Behavior. Note: this is dirty!
* Access super's behavior, dispose to get rid off its handlers, install
* custom behavior.
*/
public static class PlainCustomTableCellSkin<S, T> extends TableCellSkin<S, T> {
private BehaviorBase<?> replacedBehavior;
public PlainCustomTableCellSkin(TableCell<S, T> control) {
super(control);
replaceBehavior();
}
private void replaceBehavior() {
BehaviorBase<?> old = (BehaviorBase<?>) invokeGetField(TableCellSkin.class, this, "behavior");
old.dispose();
// at this point, InputMap mappings are empty:
// System.out.println("old mappings: " + old.getInputMap().getMappings().size());
replacedBehavior = new PlainCustomTableCellBehavior<>(getSkinnable());
}
#Override
public void dispose() {
replacedBehavior.dispose();
super.dispose();
}
}
/**
* Custom behavior that's meant to override basic handlers. Here: short-circuit
* mousePressed.
*/
public static class PlainCustomTableCellBehavior<S, T> extends TableCellBehavior<S, T> {
public PlainCustomTableCellBehavior(TableCell<S, T> control) {
super(control);
}
#Override
public void mousePressed(MouseEvent e) {
if (true) {
LOG.info("short-circuit super: " + getNode().getItem());
return;
}
super.mousePressed(e);
}
}
/**
* C&P of default tableCell in TableColumn. Extended to install custom
* skin.
*/
public static class PlainCustomTableCell<S, T> extends TableCell<S, T> {
public PlainCustomTableCell() {
}
#Override protected void updateItem(T item, boolean empty) {
if (item == getItem()) return;
super.updateItem(item, empty);
if (item == null) {
super.setText(null);
super.setGraphic(null);
} else if (item instanceof Node) {
super.setText(null);
super.setGraphic((Node)item);
} else {
super.setText(item.toString());
super.setGraphic(null);
}
}
#Override
protected Skin<?> createDefaultSkin() {
return new PlainCustomTableCellSkin<>(this);
}
}
#Override
public void start(Stage primaryStage) throws Exception {
primaryStage.setScene(new Scene(getContent(), 400, 200));
primaryStage.setTitle(FXUtils.version());
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
/**
* Reflectively access super field.
*/
public static Object invokeGetField(Class source, Object target, String name) {
try {
Field field = source.getDeclaredField(name);
field.setAccessible(true);
return field.get(target);
} catch (NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException e) {
e.printStackTrace();
}
return null;
}
#SuppressWarnings("unused")
private static final Logger LOG = Logger
.getLogger(TableCellBehaviorReplace.class.getName());
}
Edit
The suggestion inherit from the abstract skin XXSkinBase instead of the concrete XXSkin (then you are free to install whatever behavior you want, dude :-) is very reasonable and should be the first option. In the particular case of XX being TableCell, that's currently not possible, as the base class contains abstract package-private methods. Also, there are XX that don't have an abstract base (like f.i. ListCell).
Might be a bug in InputMap:
Digging into the sources I found some internal book-keeping (eventTypeMappings) parallel to mappings (these are the handlers). InputMap is listening to changes in mappings and updates the internal book-keeping on changes
mappings.addListener((ListChangeListener<Mapping<?>>) c -> {
while (c.next()) {
// TODO handle mapping removal
if (c.wasRemoved()) {
for (Mapping<?> mapping : c.getRemoved()) {
removeMapping(mapping);
}
}
// removeMapping
private void removeMapping(Mapping<?> mapping) {
// TODO
}
Meaning that the internal structure is never cleaned, particularly not when the mappings are removed in behavior.dispose(). When looking up eventHandlers - by inputMap.handle(e), see debug stacktrace shown in the question - the old handler is found in the internal book-keeping structure.
Joys of early experiments ... ;-)
At the end, a (very dirty, very hacky!) solution is to take over InputMap's job and force a cleanup of the internals:
private void replaceBehavior() {
BehaviorBase<?> old = (BehaviorBase<?>) invokeGetField(TableCellSkin.class, this, "behavior");
old.dispose();
cleanupInputMap(old.getInputMap());
// at this point, InputMap mappings are empty:
// System.out.println("old mappings: " + old.getInputMap().getMappings().size());
replacedBehavior = new PlainCustomTableCellBehavior<>(getSkinnable());
}
/**
* This is a hack around InputMap not cleaning up internals on removing mappings.
* We remove MousePressed/MouseReleased/MouseDragged mappings from the internal map.
* Beware: obviously this is dirty!
*
* #param inputMap
*/
private void cleanupInputMap(InputMap<?> inputMap) {
Map eventTypeMappings = (Map) invokeGetField(InputMap.class, inputMap, "eventTypeMappings");
eventTypeMappings.remove(MouseEvent.MOUSE_PRESSED);
eventTypeMappings.remove(MouseEvent.MOUSE_RELEASED);
eventTypeMappings.remove(MouseEvent.MOUSE_DRAGGED);
}
BTW: just in case anybody is wondering wtf - without, my hack around the missing commitOnFocusLost when editing a cell stopped working in java-9.
Try in PlainCustomTableCellSkin to inherit from the abstract class TableCellSkinBase rather than from TableCellSkin.
Then you can call the super constructor, which takes an TableCellBehaviorBase object as additional param.
Then you can save your time replacing it, by initializing it directly with the right one.
Just for more claryfication:
TableCellSkin extends TableCellSkinBase
TableCellBehavior extends TableCellBehaviorBase
One more thing. You need to also call super.init(tableCell) in your constructor.
Take the TableCellSkin class as reference.

Getting user data in NewProjectCreationPage in Eclipse Plugin

I have been successful in making a plugin. However now i need that on project creation page i add some more textboxes to get the user information. Also i need to use this information to add into the auto generated .php files made in project directory.
I want to know how can i override the WizardNewProjectCreationPage to add some more textboxes to the already given layout. I am pretty new to plugin development. Here is the code for my custom wizard.
import java.net.URI;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExecutableExtension;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.wizard.Wizard;
import org.eclipse.jface.wizard.WizardDialog;
import org.eclipse.ui.INewWizard;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.dialogs.WizardNewProjectCreationPage;
import org.eclipse.ui.wizards.newresource.BasicNewProjectResourceWizard;
import rudraxplugin.pages.MyPageOne;
import rudraxplugin.projects.RudraxSupport;
public class CustomProjectNewWizard extends Wizard implements INewWizard, IExecutableExtension {
private WizardNewProjectCreationPage _pageOne;
protected MyPageOne one;
private IConfigurationElement _configurationElement;
public CustomProjectNewWizard() {
// TODO Auto-generated constructor stub
setWindowTitle("RudraX");
}
#Override
public void init(IWorkbench workbench, IStructuredSelection selection) {
// TODO Auto-generated method stub
}
#Override
public void addPages() {
super.addPages();
_pageOne = new WizardNewProjectCreationPage("From Scratch Project Wizard");
_pageOne.setTitle("From Scratch Project");
_pageOne.setDescription("Create something from scratch.");
addPage(one);
addPage(_pageOne);
}
#Override
public boolean performFinish() {
String name = _pageOne.getProjectName();
URI location = null;
if (!_pageOne.useDefaults()) {
location = _pageOne.getLocationURI();
System.err.println("location: " + location.toString()); //$NON-NLS-1$
} // else location == null
RudraxSupport.createProject(name, location);
// Add this
BasicNewProjectResourceWizard.updatePerspective(_configurationElement);
return true;
}
#Override
public void setInitializationData(IConfigurationElement config,
String propertyName, Object data) throws CoreException {
_configurationElement = config;
// TODO Auto-generated method stub
}
}
Ask for any other code required. Any help is appreciated. Thank You.
Instead of using WizardNewProjectCreationPage directly create a new class extending WizardNewProjectCreationPage and override the createControl method to create new controls:
class MyNewProjectCreationPage extends WizardNewProjectCreationPage
{
#Override
public void createControl(Composite parent)
{
super.createControl(parent);
Composite body = (Composite)getControl();
... create new controls here
}
}

Eclipse RCP e4 Logging

I amtrying to add logging capabilities to my RCP e4 application. I found the following Snippet.
import org.eclipse.e4.core.di.annotations.Creatable;
import org.eclipse.e4.core.di.annotations.Optional;
import org.eclipse.e4.core.services.log.Logger;
#Creatable
public class LoggerWrapper extends Logger {
#Optional
#Inject
private Logger logger;
#Override
public boolean isErrorEnabled() {
if (logger != null) {
return logger.isErrorEnabled();
}
return false;
}
#Override
public void error(Throwable t, String message) {
if (logger != null && isErrorEnabled()) {
logger.error(t, withPluginInfo(message));
}
}
}
But I am not sure how to configure/initialize the Logger? Any help will be appreciated. Thanks!
If I read E4Application correctly it will always initialize the application context to contain a Logger which is implemented by org.eclipse.e4.ui.internal.workbench.WorkbenchLogger.
You could override this in the PostContextCreate method of your Life Cycle class (if you have one).
You can also inject StatusReporter which provides simple logging facilities in the Eclipse log (based on Status objects).

Reusable Liferay (6.0.6) service

I am trying to implement resuable Custom Services without using ext and servicebuilder.
I referred this article: http://www.devatwork.nl/2010/04/implementing-a-reusable-liferay-service-without-ext-or-service-builder/ , but I am confused in how should I implement this using eclipse? Following are the steps that I followed to do this:
- Created liferay-plugin project within eclipse.
- Created package containing CustomServices (interface) and CustomServicesUtil.
- Created jar file of package in step 2.
- Placed that jar file in tomcat\lib\ext\
- Then created package (with in same liferay-plugin project), that includes CutomServicesImpl and CustomServicesBaseImpl
- Defined portlet-spring.xml, service.properties, and modified web.xml (as per the article), and finally deployed the project.
On deployment, project is deployed successfully, but when I am trying to use customMethods defined in CustomServicesImpl through CustomServicesUtil.getCustomMethod(), I am getting the following error:
"java.lang.ClassNotFoundException: com.demo.custom.services.CustomServicesUtil"
I configure build path to include customservices.jar file but its not working out, still showing the same error. I don’t know whether this is the correct way to implement resuable services or not. I tried this so that i can make use of custom method in one of my project.
Here is the code for custom services:
CustomServices.java
package com.demo.custom.services;
import com.liferay.portal.model.User;
public interface CustomServices {
String getCustomName(User user);
}
CustomServicesUtil.java
package com.demo.custom.services;
import com.liferay.portal.model.User;
public class CustomServicesUtil {
private static CustomServices services;
public static CustomServices getServices() {
if (services == null) {
throw new RuntimeException("Custom Services not set");
}
return services;
}
public void setServices(CustomServices pServices) {
services = pServices;
}
public static String getCustomName(User user){
return getServices().getCustomName(user);
}
}
CustomServicesBaseImpl.java
package com.demo.custom.services.impl;
import com.demo.custom.services.CustomServices;
import com.liferay.portal.kernel.exception.SystemException;
import com.liferay.portal.service.base.PrincipalBean;
import com.liferay.portal.util.PortalUtil;
public abstract class CustomServicesBaseImpl extends PrincipalBean implements CustomServices {
protected CustomServices services;
public CustomServices getServices() {
return services;
}
public void setServices(CustomServices pServices) {
this.services = pServices;
}
protected void runSQL(String sql) throws SystemException {
try {
PortalUtil.runSQL(sql);
} catch (Exception e) {
throw new SystemException(e);
}
}
}
CustomServicesImpl.java
package com.demo.custom.services.impl;
import com.liferay.portal.model.User;
public class CustomServicesImpl extends CustomServicesBaseImpl {
#Override
public String getCustomName(User user) {
// TODO Auto-generated method stub
if(user == null){
return null;
}else{
return new StringBuffer().append(user.getFirstName()).append(" ").append(user.getLastName()).toString();
}
}
}
Here is the code of controller class of my another portlet, where i am making use of this service.
HelloCustomName.java
package com.test;
import java.io.IOException;
import javax.portlet.PortletException;
import javax.portlet.RenderRequest;
import javax.portlet.RenderResponse;
import com.demo.custom.services.CustomServicesUtil;
import com.liferay.portal.kernel.util.WebKeys;
import com.liferay.portal.model.User;
import com.liferay.portal.theme.ThemeDisplay;
import com.liferay.util.bridges.mvc.MVCPortlet;
public class HelloCustomName extends MVCPortlet {
#Override
public void doView(RenderRequest renderRequest,
RenderResponse renderResponse) throws IOException, PortletException {
System.out.println("--doview----");
ThemeDisplay themeDisplay = (ThemeDisplay)renderRequest.getAttribute(WebKeys.THEME_DISPLAY);
User user = themeDisplay.getUser();
String customName = CustomServicesUtil.getCustomName(user); //getting error here
System.out.println("customName:" + customName);
}
}
Please point me on how to implement resuable services? Any guidance will be really useful.
Thanks.
My mind, you don't need the complexity of services. Simply make utility classes and put this in to tomcat/lib/ext. Be sure that tomcat/lib/ext is correct configured in tomcat/conf/catalina.properties, something like this:
common.loader=${catalina.home}/lib/ext/*.jar

Using GWT Editors with a complex usecase

I'm trying to create a page which is very similar to the Google Form creation page.
This is how I am attempting to model it using the GWT MVP framework (Places and Activities), and Editors.
CreateFormActivity (Activity and presenter)
CreateFormView (interface for view, with nested Presenter interface)
CreateFormViewImpl (implements CreateFormView and Editor< FormProxy >
CreateFormViewImpl has the following sub-editors:
TextBox title
TextBox description
QuestionListEditor questionList
QuestionListEditor implements IsEditor< ListEditor< QuestionProxy, QuestionEditor>>
QuestionEditor implements Editor < QuestionProxy>
QuestionEditor has the following sub-editors:
TextBox questionTitle
TextBox helpText
ValueListBox questionType
An optional subeditor for each question type below.
An editor for each question type:
TextQuestionEditor
ParagraphTextQuestionEditor
MultipleChoiceQuestionEditor
CheckboxesQuestionEditor
ListQuestionEditor
ScaleQuestionEditor
GridQuestionEditor
Specific Questions:
What is the correct way to add / remove questions from the form. (see follow up question)
How should I go about creating the Editor for each question type? I attempted to listen to the questionType value changes, I'm not sure what to do after. (answered by BobV)
Should each question-type-specific editor be wrapper with an optionalFieldEditor? Since only one of can be used at a time. (answered by BobV)
How to best manage creating/removing objects deep in the object hierarchy. Ex) Specifying answers for a question number 3 which is of type multiple choice question. (see follow up question)
Can OptionalFieldEditor editor be used to wrap a ListEditor? (answered by BobV)
Implementation based on Answer
The Question Editor
public class QuestionDataEditor extends Composite implements
CompositeEditor<QuestionDataProxy, QuestionDataProxy, Editor<QuestionDataProxy>>,
LeafValueEditor<QuestionDataProxy>, HasRequestContext<QuestionDataProxy> {
interface Binder extends UiBinder<Widget, QuestionDataEditor> {}
private CompositeEditor.EditorChain<QuestionDataProxy, Editor<QuestionDataProxy>> chain;
private QuestionBaseDataEditor subEditor = null;
private QuestionDataProxy currentValue = null;
#UiField
SimplePanel container;
#UiField(provided = true)
#Path("dataType")
ValueListBox<QuestionType> dataType = new ValueListBox<QuestionType>(new Renderer<QuestionType>() {
#Override
public String render(final QuestionType object) {
return object == null ? "" : object.toString();
}
#Override
public void render(final QuestionType object, final Appendable appendable) throws IOException {
if (object != null) {
appendable.append(object.toString());
}
}
});
private RequestContext ctx;
public QuestionDataEditor() {
initWidget(GWT.<Binder> create(Binder.class).createAndBindUi(this));
dataType.setValue(QuestionType.BooleanQuestionType, true);
dataType.setAcceptableValues(Arrays.asList(QuestionType.values()));
/*
* The type drop-down UI element is an implementation detail of the
* CompositeEditor. When a question type is selected, the editor will
* call EditorChain.attach() with an instance of a QuestionData subtype
* and the type-specific sub-Editor.
*/
dataType.addValueChangeHandler(new ValueChangeHandler<QuestionType>() {
#Override
public void onValueChange(final ValueChangeEvent<QuestionType> event) {
QuestionDataProxy value;
switch (event.getValue()) {
case MultiChoiceQuestionData:
value = ctx.create(QuestionMultiChoiceDataProxy.class);
setValue(value);
break;
case BooleanQuestionData:
default:
final QuestionNumberDataProxy value2 = ctx.create(BooleanQuestionDataProxy.class);
value2.setPrompt("this value doesn't show up");
setValue(value2);
break;
}
}
});
}
/*
* The only thing that calls createEditorForTraversal() is the PathCollector
* which is used by RequestFactoryEditorDriver.getPaths().
*
* My recommendation is to always return a trivial instance of your question
* type editor and know that you may have to amend the value returned by
* getPaths()
*/
#Override
public Editor<QuestionDataProxy> createEditorForTraversal() {
return new QuestionNumberDataEditor();
}
#Override
public void flush() {
//XXX this doesn't work, no data is returned
currentValue = chain.getValue(subEditor);
}
/**
* Returns an empty string because there is only ever one sub-editor used.
*/
#Override
public String getPathElement(final Editor<QuestionDataProxy> subEditor) {
return "";
}
#Override
public QuestionDataProxy getValue() {
return currentValue;
}
#Override
public void onPropertyChange(final String... paths) {
}
#Override
public void setDelegate(final EditorDelegate<QuestionDataProxy> delegate) {
}
#Override
public void setEditorChain(final EditorChain<QuestionDataProxy, Editor<QuestionDataProxy>> chain) {
this.chain = chain;
}
#Override
public void setRequestContext(final RequestContext ctx) {
this.ctx = ctx;
}
/*
* The implementation of CompositeEditor.setValue() just creates the
* type-specific sub-Editor and calls EditorChain.attach().
*/
#Override
public void setValue(final QuestionDataProxy value) {
// if (currentValue != null && value == null) {
chain.detach(subEditor);
// }
QuestionType type = null;
if (value instanceof QuestionMultiChoiceDataProxy) {
if (((QuestionMultiChoiceDataProxy) value).getCustomList() == null) {
((QuestionMultiChoiceDataProxy) value).setCustomList(new ArrayList<CustomListItemProxy>());
}
type = QuestionType.CustomList;
subEditor = new QuestionMultipleChoiceDataEditor();
} else {
type = QuestionType.BooleanQuestionType;
subEditor = new BooleanQuestionDataEditor();
}
subEditor.setRequestContext(ctx);
currentValue = value;
container.clear();
if (value != null) {
dataType.setValue(type, false);
container.add(subEditor);
chain.attach(value, subEditor);
}
}
}
Question Base Data Editor
public interface QuestionBaseDataEditor extends HasRequestContext<QuestionDataProxy>, IsWidget {
}
Example Subtype
public class BooleanQuestionDataEditor extends Composite implements QuestionBaseDataEditor {
interface Binder extends UiBinder<Widget, BooleanQuestionDataEditor> {}
#Path("prompt")
#UiField
TextBox prompt = new TextBox();
public QuestionNumberDataEditor() {
initWidget(GWT.<Binder> create(Binder.class).createAndBindUi(this));
}
#Override
public void setRequestContext(final RequestContext ctx) {
}
}
The only issue left is that QuestionData subtype specific data isn't being displayed, or flushed. I think it has to do with the Editor setup I'm using.
For example, The value for prompt in the BooleanQuestionDataEditor is neither set nor flushed, and is null in the rpc payload.
My guess is: Since the QuestionDataEditor implements LeafValueEditor, the driver will not visit the subeditor, even though it has been attached.
Big thanks to anyone who can help!!!
Fundamentally, you want a CompositeEditor to handle cases where objects are dynamically added or removed from the Editor hierarchy. The ListEditor and OptionalFieldEditor adaptors implement CompositeEditor.
If the information required for the different types of questions is fundamentally orthogonal, then multiple OptionalFieldEditor could be used with different fields, one for each question type. This will work when you have only a few question types, but won't really scale well in the future.
A different approach, that will scale better would be to use a custom implementation of a CompositeEditor + LeafValueEditor that handles a polymorphic QuestionData type hierarchy. The type drop-down UI element would become an implementation detail of the CompositeEditor. When a question type is selected, the editor will call EditorChain.attach() with an instance of a QuestionData subtype and the type-specific sub-Editor. The newly-created QuestionData instance should be retained to implement LeafValueEditor.getValue(). The implementation of CompositeEditor.setValue() just creates the type-specific sub-Editor and calls EditorChain.attach().
FWIW, OptionalFieldEditor can be used with ListEditor or any other editor type.
We implemented similar approach (see accepted answer) and it works for us like this.
Since driver is initially unaware of simple editor paths that might be used by sub-editors, every sub-editor has own driver:
public interface CreatesEditorDriver<T> {
RequestFactoryEditorDriver<T, ? extends Editor<T>> createDriver();
}
public interface RequestFactoryEditor<T> extends CreatesEditorDriver<T>, Editor<T> {
}
Then we use the following editor adapter that would allow any sub-editor that implements RequestFactoryEditor to be used. This is our workaround to support polimorphism in editors:
public static class DynamicEditor<T>
implements LeafValueEditor<T>, CompositeEditor<T, T, RequestFactoryEditor<T>>, HasRequestContext<T> {
private RequestFactoryEditorDriver<T, ? extends Editor<T>> subdriver;
private RequestFactoryEditor<T> subeditor;
private T value;
private EditorDelegate<T> delegate;
private RequestContext ctx;
public static <T> DynamicEditor<T> of(RequestFactoryEditor<T> subeditor) {
return new DynamicEditor<T>(subeditor);
}
protected DynamicEditor(RequestFactoryEditor<T> subeditor) {
this.subeditor = subeditor;
}
#Override
public void setValue(T value) {
this.value = value;
subdriver = null;
if (null != value) {
RequestFactoryEditorDriver<T, ? extends Editor<T>> newSubdriver = subeditor.createDriver();
if (null != ctx) {
newSubdriver.edit(value, ctx);
} else {
newSubdriver.display(value);
}
subdriver = newSubdriver;
}
}
#Override
public T getValue() {
return value;
}
#Override
public void flush() {
if (null != subdriver) {
subdriver.flush();
}
}
#Override
public void onPropertyChange(String... paths) {
}
#Override
public void setDelegate(EditorDelegate<T> delegate) {
this.delegate = delegate;
}
#Override
public RequestFactoryEditor<T> createEditorForTraversal() {
return subeditor;
}
#Override
public String getPathElement(RequestFactoryEditor<T> subEditor) {
return delegate.getPath();
}
#Override
public void setEditorChain(EditorChain<T, RequestFactoryEditor<T>> chain) {
}
#Override
public void setRequestContext(RequestContext ctx) {
this.ctx = ctx;
}
}
Our example sub-editor:
public static class VirtualProductEditor implements RequestFactoryEditor<ProductProxy> {
interface Driver extends RequestFactoryEditorDriver<ProductProxy, VirtualProductEditor> {}
private static final Driver driver = GWT.create(Driver.class);
public Driver createDriver() {
driver.initialize(this);
return driver;
}
...
}
Our usage example:
#Path("")
DynamicEditor<ProductProxy> productDetailsEditor;
...
public void setProductType(ProductType type){
if (ProductType.VIRTUAL==type){
productDetailsEditor = DynamicEditor.of(new VirtualProductEditor());
} else if (ProductType.PHYSICAL==type){
productDetailsEditor = DynamicEditor.of(new PhysicalProductEditor());
}
}
Would be great to hear your comments.
Regarding your question why subtype specific data isn't displayed or flushed:
My scenario is a little bit different but I made the following observation:
GWT editor databinding does not work as one would expect with abstract editors in the editor hierarchy. The subEditor declared in your QuestionDataEditor is of type QuestionBaseDataEditor and this is fully abstract type (an interface). When looking for fields/sub editors to populate with data/flush GWT takes all the fields declared in this type. Since QuestionBaseDataEditor has no sub editors declared nothing is displayed/flushed. From debugging I found out that is happens due to GWT using a generated EditorDelegate for that abstract type rather than the EditorDelegate for the concrete subtype present at that moment.
In my case all the concrete sub editors had the same types of leaf value editors (I had two different concrete editors one to display and one to edit the same bean type) so I could do something like this to work around this limitation:
interface MyAbstractEditor1 extends Editor<MyBean>
{
LeafValueEditor<String> description();
}
// or as an alternative
abstract class MyAbstractEditor2 implements Editor<MyBean>
{
#UiField protected LeafValueEditor<String> name;
}
class MyConcreteEditor extends MyAbstractEditor2 implements MyAbstractEditor1
{
#UiField TextBox description;
public LeafValueEditor<String> description()
{
return description;
}
// super.name is bound to a TextBox using UiBinder :)
}
Now GWT finds the subeditors in the abstract base class and in both cases I get the corresponding fields name and description populated and flushed.
Unfortunately this approach is not suitable when the concrete subeditors have different values in your bean structure to edit :(
I think this is a bug of the editors framework GWT code generation, that can only be solved by the GWT development team.
Isn't the fundamental problem that the binding happens at compile time so will only bind to QuestionDataProxy so won't have sub-type specific bindings? The CompositeEditor javadoc says "An interface that indicates that a given Editor is composed of an unknown number of sub-Editors all of the same type" so that rules this usage out?
At my current job I'm pushing to avoid polymorphism altogether as the RDBMS doesn't support it either. Sadly we do have some at the moment so I'm experimenting with a dummy wrapper class that exposes all the sub-types with specific getters so the compiler has something to work on. Not pretty though.
Have you seen this post: http://markmail.org/message/u2cff3mfbiboeejr this seems along the right lines.
I'm a bit worried about code bloat though.
Hope that makes some sort of sense!