+ * The completion state of the wizard page will only be set to true
+ * if all of the following conditions are met:
+ *
+ * By default, this method returns false. Subclasses will
+ * typically want to overwrite this method to return whether any of
+ * the binding's update strategies is intended to be run asynchronously.
+ * However, subclasses may always decide not to execute the updates
+ * asynchronously.
+ *
+ * By default, this method returns true if and only if the
+ * converter associated to this strategy is intended to be executed
+ * asynchronously. Clients may extend without having to call the super
+ * implementation.
+ *
+ * Note that even if this method returns true, there is no
+ * guarantee as of whether the list update will indeed by executed
+ * asynchronously or not.
+ *
+ * By default, this method returns false.
+ *
+ * By default, this method returns true if and only if
+ * any of the validators or the converter associated to this strategy
+ * is intended to be executed asynchronously. Clients may extend without
+ * having to call the super implementation.
+ *
+ * Note that even if this method returns true, there is no
+ * guarantee as of whether the value update will indeed by executed
+ * asynchronously or not.
+ *
+ * This method returns true if and only if any of the
+ * binding's update strategies is intended to be run asynchronously.
+ * Thereby, the individual updates of this binding are always guaranteed to
+ * be executed in the correct order, thus ensuring that the target and model
+ * values will never get out of sync due to the asynchronous nature of the
+ * updates.
+ *
+ * In case the updates are executed asynchronously, the staleness state of + * the validation status observable can be used to determine whether there + * are any pending updates. This allows for awaiting the termination of + * those updates, if desired, by tracking the observable's staleness state. + *
+ * + * @return whether the updates performed by this binding are executed + * asynchronously. + * + * @see UpdateValueStrategy#isAsync() + */ + public boolean isAsync() { + return targetToModel.isAsync() || modelToTarget.isAsync(); + } + + /** * Incorporates the providednewStats into the
* multieStatus.
*
@@ -128,7 +184,6 @@
final IObservableValue destination,
final UpdateValueStrategy updateValueStrategy,
final boolean explicit, final boolean validateOnly) {
-
final int policy = updateValueStrategy.getUpdatePolicy();
if (policy == UpdateValueStrategy.POLICY_NEVER)
return;
@@ -137,78 +192,99 @@
source.getRealm().exec(new Runnable() {
public void run() {
- boolean destinationRealmReached = false;
- final MultiStatus multiStatus = BindingStatus.ok();
- try {
- // Get value
- Object value = source.getValue();
-
- // Validate after get
- IStatus status = updateValueStrategy
- .validateAfterGet(value);
- if (!mergeStatus(multiStatus, status))
- return;
-
- // Convert value
- final Object convertedValue = updateValueStrategy
- .convert(value);
-
- // Validate after convert
- status = updateValueStrategy
- .validateAfterConvert(convertedValue);
- if (!mergeStatus(multiStatus, status))
- return;
- if (policy == UpdateValueStrategy.POLICY_CONVERT
- && !explicit)
- return;
-
- // Validate before set
- status = updateValueStrategy
- .validateBeforeSet(convertedValue);
- if (!mergeStatus(multiStatus, status))
- return;
- if (validateOnly)
- return;
-
- // Set value
- destinationRealmReached = true;
- destination.getRealm().exec(new Runnable() {
- public void run() {
- if (destination == target) {
- updatingTarget = true;
- } else {
- updatingModel = true;
- }
- try {
- IStatus setterStatus = updateValueStrategy
- .doSet(destination, convertedValue);
-
- mergeStatus(multiStatus, setterStatus);
- } finally {
- if (destination == target) {
- updatingTarget = false;
- } else {
- updatingModel = false;
+ // Get value
+ final Object value = source.getValue();
+
+ UpdateRunnable update = new UpdateRunnable() {
+ public void run() {
+ boolean destinationRealmReached = false;
+ final MultiStatus multiStatus = BindingStatus.ok();
+ try {
+ // Validate after get
+ IStatus status = updateValueStrategy
+ .validateAfterGet(value);
+ if (!mergeStatus(multiStatus, status))
+ return;
+
+ // Convert value
+ final Object convertedValue = updateValueStrategy
+ .convert(value);
+
+ // Validate after convert
+ status = updateValueStrategy
+ .validateAfterConvert(convertedValue);
+ if (!mergeStatus(multiStatus, status))
+ return;
+ if (policy == UpdateValueStrategy.POLICY_CONVERT
+ && !explicit)
+ return;
+
+ // Validate before set
+ status = updateValueStrategy
+ .validateBeforeSet(convertedValue);
+ if (!mergeStatus(multiStatus, status))
+ return;
+ if (validateOnly)
+ return;
+
+ // Set value
+ destinationRealmReached = true;
+ destination.getRealm().exec(new Runnable() {
+ public void run() {
+ // If the update has been canceled before
+ // writing to the destination observable, we
+ // do not set the validation status, so we
+ // return outside the below try block.
+ if (isCanceled()) {
+ notifyDone();
+ return;
+ }
+
+ if (destination == target) {
+ updatingTarget = true;
+ } else {
+ updatingModel = true;
+ }
+ try {
+ IStatus setterStatus = updateValueStrategy
+ .doSet(destination,
+ convertedValue);
+
+ mergeStatus(multiStatus, setterStatus);
+ } finally {
+ if (destination == target) {
+ updatingTarget = false;
+ } else {
+ updatingModel = false;
+ }
+ setValidationStatus(multiStatus);
+ notifyDone();
+ }
+ }
+ });
+ } catch (Exception ex) {
+ // This check is necessary as in 3.2.2 Status
+ // doesn't accept a null message (bug 177264).
+ String message = (ex.getMessage() != null) ? ex
+ .getMessage() : ""; //$NON-NLS-1$
+
+ mergeStatus(multiStatus, new Status(IStatus.ERROR,
+ Policy.JFACE_DATABINDING, IStatus.ERROR,
+ message, ex));
+ } finally {
+ if (!destinationRealmReached) {
+ // Set the validation status unless the update
+ // has been canceled in the meanwhile.
+ if (!isCanceled()) {
+ setValidationStatus(multiStatus);
}
- setValidationStatus(multiStatus);
+ notifyDone();
}
}
- });
- } catch (Exception ex) {
- // This check is necessary as in 3.2.2 Status
- // doesn't accept a null message (bug 177264).
- String message = (ex.getMessage() != null) ? ex
- .getMessage() : ""; //$NON-NLS-1$
-
- mergeStatus(multiStatus, new Status(IStatus.ERROR,
- Policy.JFACE_DATABINDING, IStatus.ERROR, message,
- ex));
- } finally {
- if (!destinationRealmReached) {
- setValidationStatus(multiStatus);
}
+ };
- }
+ updateExecutor.execute(update, !explicit);
}
});
}
@@ -230,6 +306,8 @@
}
public void dispose() {
+ updateExecutor.terminate();
+
if (targetChangeListener != null) {
target.removeValueChangeListener(targetChangeListener);
targetChangeListener = null;
Index: src/org/eclipse/core/internal/databinding/conversion/ObjectToStringConverter.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.core.databinding/src/org/eclipse/core/internal/databinding/conversion/ObjectToStringConverter.java,v
retrieving revision 1.1
diff -u -r1.1 ObjectToStringConverter.java
--- src/org/eclipse/core/internal/databinding/conversion/ObjectToStringConverter.java 16 Mar 2007 21:19:39 -0000 1.1
+++ src/org/eclipse/core/internal/databinding/conversion/ObjectToStringConverter.java 16 Jun 2008 20:08:56 -0000
@@ -53,4 +53,7 @@
return String.class;
}
+ public boolean isAsync() {
+ return false;
+ }
}
Index: src/org/eclipse/core/internal/databinding/conversion/StringToBooleanPrimitiveConverter.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.core.databinding/src/org/eclipse/core/internal/databinding/conversion/StringToBooleanPrimitiveConverter.java,v
retrieving revision 1.3
diff -u -r1.3 StringToBooleanPrimitiveConverter.java
--- src/org/eclipse/core/internal/databinding/conversion/StringToBooleanPrimitiveConverter.java 16 Apr 2008 02:51:52 -0000 1.3
+++ src/org/eclipse/core/internal/databinding/conversion/StringToBooleanPrimitiveConverter.java 16 Jun 2008 20:08:56 -0000
@@ -85,4 +85,7 @@
return Boolean.TYPE;
}
+ public boolean isAsync() {
+ return false;
+ }
}
Index: src/org/eclipse/core/internal/databinding/conversion/StringToDateConverter.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.core.databinding/src/org/eclipse/core/internal/databinding/conversion/StringToDateConverter.java,v
retrieving revision 1.1
diff -u -r1.1 StringToDateConverter.java
--- src/org/eclipse/core/internal/databinding/conversion/StringToDateConverter.java 16 Mar 2007 21:19:38 -0000 1.1
+++ src/org/eclipse/core/internal/databinding/conversion/StringToDateConverter.java 16 Jun 2008 20:08:56 -0000
@@ -32,5 +32,9 @@
public Object getToType() {
return Date.class;
- }
+ }
+
+ public boolean isAsync() {
+ return false;
+ }
}
Index: src/org/eclipse/core/internal/databinding/conversion/DateToStringConverter.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.core.databinding/src/org/eclipse/core/internal/databinding/conversion/DateToStringConverter.java,v
retrieving revision 1.1
diff -u -r1.1 DateToStringConverter.java
--- src/org/eclipse/core/internal/databinding/conversion/DateToStringConverter.java 16 Mar 2007 21:19:38 -0000 1.1
+++ src/org/eclipse/core/internal/databinding/conversion/DateToStringConverter.java 16 Jun 2008 20:08:56 -0000
@@ -35,5 +35,9 @@
public Object getToType() {
return String.class;
- }
+ }
+
+ public boolean isAsync() {
+ return false;
+ }
}
Index: src/org/eclipse/core/internal/databinding/conversion/IdentityConverter.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.core.databinding/src/org/eclipse/core/internal/databinding/conversion/IdentityConverter.java,v
retrieving revision 1.2
diff -u -r1.2 IdentityConverter.java
--- src/org/eclipse/core/internal/databinding/conversion/IdentityConverter.java 7 Nov 2007 03:19:45 -0000 1.2
+++ src/org/eclipse/core/internal/databinding/conversion/IdentityConverter.java 16 Jun 2008 20:08:56 -0000
@@ -107,4 +107,7 @@
return toType;
}
+ public boolean isAsync() {
+ return false;
+ }
}
Index: src/org/eclipse/core/internal/databinding/conversion/StringToCharacterConverter.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.core.databinding/src/org/eclipse/core/internal/databinding/conversion/StringToCharacterConverter.java,v
retrieving revision 1.2
diff -u -r1.2 StringToCharacterConverter.java
--- src/org/eclipse/core/internal/databinding/conversion/StringToCharacterConverter.java 7 Nov 2007 03:19:45 -0000 1.2
+++ src/org/eclipse/core/internal/databinding/conversion/StringToCharacterConverter.java 16 Jun 2008 20:08:56 -0000
@@ -70,6 +70,10 @@
return primitiveTarget ? Character.TYPE : Character.class;
}
+ public boolean isAsync() {
+ return false;
+ }
+
/**
* @param primitive
* @return converter
Index: src/org/eclipse/core/internal/databinding/Queue.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.core.databinding/src/org/eclipse/core/internal/databinding/Queue.java,v
retrieving revision 1.3
diff -u -r1.3 Queue.java
--- src/org/eclipse/core/internal/databinding/Queue.java 9 May 2008 14:13:00 -0000 1.3
+++ src/org/eclipse/core/internal/databinding/Queue.java 16 Jun 2008 20:08:56 -0000
@@ -72,4 +72,12 @@
public boolean isEmpty() {
return first == null;
}
+
+ /**
+ * Removes all elements from this queue.
+ */
+ public void clear() {
+ first = null;
+ last = null;
+ }
}
\ No newline at end of file
Index: META-INF/MANIFEST.MF
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.core.databinding/META-INF/MANIFEST.MF,v
retrieving revision 1.14
diff -u -r1.14 MANIFEST.MF
--- META-INF/MANIFEST.MF 11 Apr 2008 22:18:08 -0000 1.14
+++ META-INF/MANIFEST.MF 16 Jun 2008 20:08:55 -0000
@@ -22,7 +22,8 @@
org.eclipse.core.internal.databinding.observable.masterdetail;x-friends:="org.eclipse.jface.tests.databinding",
org.eclipse.core.internal.databinding.observable.tree;x-friends:="org.eclipse.jface.databinding,org.eclipse.jface.tests.databinding",
org.eclipse.core.internal.databinding.validation;x-friends:="org.eclipse.jface.tests.databinding"
-Require-Bundle: org.eclipse.equinox.common;bundle-version="[3.2.0,4.0.0)"
+Require-Bundle: org.eclipse.equinox.common;bundle-version="[3.2.0,4.0.0)",
+ org.eclipse.core.jobs
Import-Package-Comment: see http://wiki.eclipse.org/
Import-Package: com.ibm.icu.text,
org.osgi.framework;version="[1.4.0,2.0.0)";resolution:=optional,
Index: src/org/eclipse/core/databinding/conversion/Converter.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.core.databinding/src/org/eclipse/core/databinding/conversion/Converter.java,v
retrieving revision 1.3
diff -u -r1.3 Converter.java
--- src/org/eclipse/core/databinding/conversion/Converter.java 22 May 2007 19:22:18 -0000 1.3
+++ src/org/eclipse/core/databinding/conversion/Converter.java 16 Jun 2008 20:08:55 -0000
@@ -40,4 +40,10 @@
return toType;
}
+ /**
+ * By default, this method returns false.
+ */
+ public boolean isAsync() {
+ return false;
+ }
}
Index: src/org/eclipse/core/databinding/conversion/IConverter.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.core.databinding/src/org/eclipse/core/databinding/conversion/IConverter.java,v
retrieving revision 1.8
diff -u -r1.8 IConverter.java
--- src/org/eclipse/core/databinding/conversion/IConverter.java 9 May 2008 14:13:00 -0000 1.8
+++ src/org/eclipse/core/databinding/conversion/IConverter.java 16 Jun 2008 20:08:55 -0000
@@ -50,4 +50,19 @@
* @return the converted object, of type {@link #getToType()}
*/
public Object convert(Object fromObject);
+
+ /**
+ * Returns whether the {@link #convert(Object)} method of this converter is
+ * intended to be executed asynchronously.
+ *
+ *
+ * Note that even if this method returns true, there is no
+ * guarantee as of whether the conversion will indeed by executed
+ * asynchronously or not.
+ *
+ * In case the validation of this MultiValidator is performed + * asynchronously, the staleness state of the validation status observable + * can be used to determine whether there are any pending validations. This + * allows for awaiting the termination of those validations, if desired, by + * tracking the observable's staleness state. + * * @return an {@link IObservableValue} whose value is always the current * validation status of this MultiValidator. */ @@ -232,6 +242,68 @@ protected abstract IStatus validate(); /** + * Notifies the MultiValidator that the current validation status is being + * computed asynchronously and is not available yet. + * + *
+ * Subclasses should invoke this method whenever the {@link #validate() + * validation} is performed asynchronously. Calling this method guarantees + * that the {@link #getValidationStatus() validation status observable} is + * correctly set to be stale. + * + *
+ * Typically, this method should be called from within the + * {@link #validate()} method when the asynchronous validation is started + * while a reasonable validation status must always be returned to be used + * while the pending validation has not terminated. Once the validation is + * available, it can be passed to the MultiValidator by calling the + * {@link #exitStale(IStatus)} method. + * + *
+ * Note: This method must be called from within the MultiValidator's realm. + * + * @see #exitStale(IStatus) + * @see IObservableValue#isStale() + */ + protected final void enterStale() { + stale = true; + validationStatus.fireStale(); + } + + /** + * Notifies the MultiValidator that an asynchronous validation has + * terminated which resulted in the given validation status. + * + *
+ * This method sets the given status as the current validation
+ * status and sets the {@link #getValidationStatus() validation status
+ * observable} to not be stale anymore.
+ *
+ *
+ * Note: This method must be called from within the MultiValidator's realm. + * + * @param status + * the resulting status of the terminated validation. + * + * @see #enterStale() + * @see IObservableValue#isStale() + */ + protected final void exitStale(IStatus status) { + stale = false; + Object oldStatus = validationStatus.getValue(); + validationStatus.setValue(status); + + // In order to signal that the validation status observable is not stale + // anymore, we must always fire a value change event, even if the + // validation status has not changed. In the latter case, we must do so + // explicitly. + if (oldStatus.equals(status)) { + validationStatus.fireValueChange(Diffs.createValueDiff(oldStatus, + status)); + } + } + + /** * Returns a wrapper {@link IObservableValue} which stays in sync with the * given target observable only when the validation status is valid. * Statuses of {@link IStatus#OK OK}, {@link IStatus#INFO INFO} or @@ -366,4 +438,25 @@ super.dispose(); } + private class ValidationStatusObservableValue extends WritableValue { + + public ValidationStatusObservableValue(Realm realm) { + super(realm, ValidationStatus.ok(), IStatus.class); + } + + public boolean isStale() { + ObservableTracker.getterCalled(this); + return stale; + } + + protected void fireStale() { + // Make the method accessible to the MultiValidator class. + super.fireStale(); + } + + protected void fireValueChange(ValueDiff diff) { + // Make the method accessible to the MultiValidator class. + super.fireValueChange(diff); + } + } } Index: src/org/eclipse/core/internal/databinding/observable/UnmodifiableObservableValue.java =================================================================== RCS file: /cvsroot/eclipse/org.eclipse.core.databinding/src/org/eclipse/core/internal/databinding/observable/UnmodifiableObservableValue.java,v retrieving revision 1.2 diff -u -r1.2 UnmodifiableObservableValue.java --- src/org/eclipse/core/internal/databinding/observable/UnmodifiableObservableValue.java 22 Feb 2008 05:33:48 -0000 1.2 +++ src/org/eclipse/core/internal/databinding/observable/UnmodifiableObservableValue.java 16 Jun 2008 20:08:56 -0000 @@ -55,4 +55,8 @@ public Object getValueType() { return wrappedValue.getValueType(); } + + public boolean isStale() { + return wrappedValue.isStale(); + } } Index: src/org/eclipse/core/internal/databinding/UpdateExecutor.java =================================================================== RCS file: src/org/eclipse/core/internal/databinding/UpdateExecutor.java diff -N src/org/eclipse/core/internal/databinding/UpdateExecutor.java --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ src/org/eclipse/core/internal/databinding/UpdateExecutor.java 1 Jan 1970 00:00:00 -0000 @@ -0,0 +1,234 @@ +/******************************************************************************* + * Copyright (c) 2008 Ovidio Mallo and others. + * All rights reserved. This program and the accompanying materials + * are made available under the terms of the Eclipse Public License v1.0 + * which accompanies this distribution, and is available at + * http://www.eclipse.org/legal/epl-v10.html + * + * Contributors: + * Ovidio Mallo - initial API and implementation (bug 233191) + ******************************************************************************/ + +package org.eclipse.core.internal.databinding; + +import java.util.HashSet; +import java.util.Iterator; +import java.util.Set; + +import org.eclipse.core.runtime.IProgressMonitor; +import org.eclipse.core.runtime.IStatus; +import org.eclipse.core.runtime.Status; +import org.eclipse.core.runtime.jobs.Job; + +/** + * Simple class to manage the execution of {@link UpdateRunnable}s intended to + * be used for performing the updates of a binding. + * + *
+ * This class is thread safe and supports the synchronous as well as + * asynchronous execution of a set of UpdateRunnables where consecutive updates + * are guaranteed to be executed in the correct order. In addition, this class + * allows for tracking the set of pending updates which can eventually be + * canceled upon scheduling a new update which makes previous updates obsolete. + *
+ * + * @see #execute(UpdateRunnable, boolean) + * @see #hasPendingUpdates() + */ +public class UpdateExecutor { + + private final boolean isAsync; + + private final Runnable schedulingEventCallback; + + private final Set pendingUpdates = new HashSet(); + + private final UpdateJob updateJob; + + /** + * Creates a new UpdateExecutor which will run the individual updates either + * synchronously or asynchronously. + * + * @param isAsync + * whether the UpdateRunnables passed to this UpdateExecutor + * should be executed asynchronously. + * @param schedulingEventCallback + * a callback Runnable which will be executed whenever some + * scheduling event in the execution of the updates happened. The + * code in the runnable can then use this classes API to retrieve + * the relevant information. May benull.
+ */
+ public UpdateExecutor(boolean isAsync, Runnable schedulingEventCallback) {
+ this.isAsync = isAsync;
+ this.schedulingEventCallback = schedulingEventCallback;
+
+ // Only instantiate the UpdateJob if we are in asynchronous mode.
+ if (isAsync) {
+ this.updateJob = new UpdateJob();
+ this.updateJob.setSystem(true);
+ } else {
+ this.updateJob = null;
+ }
+ }
+
+ /**
+ * Executes the given {@link UpdateRunnable update} and eventually tries to
+ * cancel previous, still pending updates, if desired.
+ *
+ * @param update
+ * the new update to execute.
+ * @param cancelPendingUpdates
+ * whether previous, still pending updates, should be requested
+ * to be {@link UpdateRunnable#cancel() canceled} before
+ * executing the new update.
+ *
+ * @see UpdateRunnable#run()
+ * @see UpdateRunnable#cancel()
+ */
+ public void execute(UpdateRunnable update, boolean cancelPendingUpdates) {
+ // If requested, we try to cancel previous updates.
+ if (cancelPendingUpdates) {
+ cancelPendingUpdates();
+ }
+
+ // The executor must be set on the UpdateRunnable in order to get
+ // notified of the update's termination.
+ update.setExecutor(this);
+
+ // Add the new update to the set of pending updates.
+ synchronized (pendingUpdates) {
+ pendingUpdates.add(update);
+ }
+
+ // Right before starting the update, we notify about the new update.
+ if (schedulingEventCallback != null) {
+ schedulingEventCallback.run();
+ }
+
+ if (isAsync) {
+ synchronized (updateJob.updateQueue) {
+ // Whenever we are adding a new update to an empty queue, we
+ // must re-schedule the UpdateJob. Note that it is OK to do this
+ // before actually adding the update to the queue since we are
+ // already holding the lock on the queue at this point.
+ if (updateJob.updateQueue.isEmpty()) {
+ updateJob.schedule();
+ }
+ updateJob.updateQueue.enqueue(update);
+ }
+ } else {
+ // In synchronous mode, we simply execute the run method.
+ update.run();
+ }
+ }
+
+ /**
+ * Indicates that the given update was running and has now terminated.
+ *
+ * @param update
+ * the update which has terminated.
+ *
+ * @see #hasPendingUpdates()
+ * @see UpdateRunnable#notifyDone()
+ */
+ /* package */void endUpdate(UpdateRunnable update) {
+ synchronized (pendingUpdates) {
+ pendingUpdates.remove(update);
+ }
+
+ if (schedulingEventCallback != null) {
+ schedulingEventCallback.run();
+ }
+ }
+
+ /**
+ * Returns whether there are any pending updates to be executed on behalf of
+ * this UpdateExecutor.
+ *
+ * + * Note that an update is defined to be pending as soon as it has been + * passed to this UpdateExecutor for + * {@link #execute(UpdateRunnable, boolean) execution}, regardless of + * whether the update is already running or not. + *
+ * + * @return whether there are any pending updates to be executed on behalf of + * this UpdateExecutor. + */ + public boolean hasPendingUpdates() { + synchronized (pendingUpdates) { + return !pendingUpdates.isEmpty(); + } + } + + /** + * Requests all the pending updates to be canceled. + * + *+ * This method guarantees that by the end of its execution, all the pending + * updates have been requested to be {@link UpdateRunnable#cancel() + * canceled} and that updates which have not been started yet (if in + * asynchronous mode) will never be run. + *
+ * + * @see UpdateRunnable#cancel() + */ + private void cancelPendingUpdates() { + synchronized (pendingUpdates) { + // Cancel all the pending updates. + for (Iterator iter = pendingUpdates.iterator(); iter.hasNext();) { + UpdateRunnable update = (UpdateRunnable) iter.next(); + update.cancel(); + } + pendingUpdates.clear(); + } + + if (isAsync) { + // If in asynchronous mode, we must also clear the queue of updates + // waiting to be run. + synchronized (updateJob.updateQueue) { + updateJob.updateQueue.clear(); + } + } + } + + /** + * Terminates the UpdateExecutor by canceling any eventual pending update. + * + *+ * Note that once this method has been called, no further updates should be + * run on behalf of this UpdateExecutor. + *
+ */ + public void terminate() { + cancelPendingUpdates(); + + if (schedulingEventCallback != null) { + schedulingEventCallback.run(); + } + } + + private class UpdateJob extends Job { + + private final Queue updateQueue = new Queue(); + + public UpdateJob() { + super("Update Job"); //$NON-NLS-1$ + } + + protected IStatus run(IProgressMonitor monitor) { + while (true) { + UpdateRunnable update; + synchronized (updateQueue) { + // As soon as we get out of work, we return in order to + // release the Thread on whose behalf the job is running. + if (updateQueue.isEmpty()) { + return Status.OK_STATUS; + } + update = (UpdateRunnable) updateQueue.dequeue(); + } + update.run(); + } + } + } +} Index: src/org/eclipse/core/databinding/validation/IValidator2.java =================================================================== RCS file: src/org/eclipse/core/databinding/validation/IValidator2.java diff -N src/org/eclipse/core/databinding/validation/IValidator2.java --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ src/org/eclipse/core/databinding/validation/IValidator2.java 1 Jan 1970 00:00:00 -0000 @@ -0,0 +1,34 @@ +/******************************************************************************* + * Copyright (c) 2008 Ovidio Mallo and others. + * All rights reserved. This program and the accompanying materials + * are made available under the terms of the Eclipse Public License v1.0 + * which accompanies this distribution, and is available at + * http://www.eclipse.org/legal/epl-v10.html + * + * Contributors: + * Ovidio Mallo - initial API and implementation (bug 233191) + ******************************************************************************/ + +package org.eclipse.core.databinding.validation; + +/** + * Extension of the {@link IValidator} interface which adds API for expressing + * the intend of a validator to be executed asynchronously. + */ +public interface IValidator2 extends IValidator { + + /** + * Returns whether the {@link #validate(Object)} method of this validator is + * intended to be executed asynchronously. + * + *
+ * Note that even if this method returns true, there is no
+ * guarantee as of whether the validation will indeed by executed
+ * asynchronously or not.
+ *
+ * This observable provides some convenience API to signal a possible change in
+ * its staleness state. Whenever the staleness of the validation observable
+ * changes (or may have changed), {@link #updateStaleness()} should be called
+ * which either fires a stale event in case the method {@link #isStale()}
+ * returns true, or else, a value change event is fired in order to
+ * signal that the observable is not stale anymore. Subclasses must implement
+ * the {@link #isStale()} method.
+ *
Status.OK_STATUS in the given realm.
+ *
+ * @param realm
+ * the observable's realm.
+ */
+ public UpdateValidationObservableValue(Realm realm) {
+ super(realm);
+ }
+
+ protected Object doGetValue() {
+ return value;
+ }
+
+ protected void doSetValue(Object value) {
+ Object oldValue = this.value;
+ this.value = value;
+ if (!Util.equals(oldValue, value)) {
+ fireValueChange(Diffs.createValueDiff(oldValue, value));
+ }
+ }
+
+ /**
+ * Updates the staleness of this validation by either firing a stale event
+ * in case the method {@link #isStale()} returns true, or else,
+ * by firing a value change event in order to signal that the observable is
+ * not stale anymore.
+ */
+ public void updateStaleness() {
+ if (isStale()) {
+ fireStale();
+ } else {
+ // This synthetic value change event is merely used to signal that
+ // the observable is not stale anymore.
+ fireValueChange(Diffs.createValueDiff(getValue(), getValue()));
+ }
+ }
+
+ public abstract boolean isStale();
+
+ public Object getValueType() {
+ return IStatus.class;
+ }
+}
Index: src/org/eclipse/core/internal/databinding/UpdateRunnable.java
===================================================================
RCS file: src/org/eclipse/core/internal/databinding/UpdateRunnable.java
diff -N src/org/eclipse/core/internal/databinding/UpdateRunnable.java
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ src/org/eclipse/core/internal/databinding/UpdateRunnable.java 1 Jan 1970 00:00:00 -0000
@@ -0,0 +1,92 @@
+/*******************************************************************************
+ * Copyright (c) 2008 Ovidio Mallo and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ * Ovidio Mallo - initial API and implementation (bug 233191)
+ ******************************************************************************/
+
+package org.eclipse.core.internal.databinding;
+
+/**
+ * Simple implementation of a Runnable which can be used to have a
+ * binding update executed by an {@link UpdateExecutor}.
+ *
+ *
+ * This thread safe class adds methods to support a collaborative
+ * {@link #cancel() canceling} of a running update. In addition, in order to
+ * allow for an UpdateExecutor to keep track of the updates
+ * currently running on its behalf, every UpdateRunnable is
+ * responsible for {@link #notifyDone() notifying} the executor about its
+ * completion.
+ *
UpdateExecutor on whose behalf this update is
+ * executed.
+ */
+ /* package */final synchronized void setExecutor(UpdateExecutor executor) {
+ this.executor = executor;
+ }
+
+ /**
+ * Signals that this update has completed.
+ *
+ * + * Calling this method is typically the responsibility of the running update + * itself and is used to allow for the {@link UpdateExecutor executor} of + * this update to keep track of the pending updates. + *
+ * + *+ * Note that if an update terminates asynchronously, this method should only + * be called as soon as the update really terminates and not already when + * reaching the end of the {@link #run()} method. + *
+ * + * @see #setExecutor(UpdateExecutor) + * @see UpdateExecutor#endUpdate(UpdateRunnable) + */ + protected final synchronized void notifyDone() { + if (executor != null) { + executor.endUpdate(this); + } + } + + /** + * Returns whether this update has been requested to be canceled. + * + * @return whether this update has been requested to be canceled. + * + * @see #cancel() + */ + public final boolean isCanceled() { + return canceled; + } + + /** + * Requests this update to be canceled while it is up to the running update + * to decide if and when the update can be canceled before its natural + * completion. + * + * @see #isCanceled() + */ + public final void cancel() { + this.canceled = true; + } +} #P org.eclipse.jface.examples.databinding Index: src/org/eclipse/jface/examples/databinding/nestedselection/TestMasterDetail.java =================================================================== RCS file: /cvsroot/eclipse/org.eclipse.jface.examples.databinding/src/org/eclipse/jface/examples/databinding/nestedselection/TestMasterDetail.java,v retrieving revision 1.18 diff -u -r1.18 TestMasterDetail.java --- src/org/eclipse/jface/examples/databinding/nestedselection/TestMasterDetail.java 16 Mar 2007 21:19:35 -0000 1.18 +++ src/org/eclipse/jface/examples/databinding/nestedselection/TestMasterDetail.java 16 Jun 2008 20:09:00 -0000 @@ -252,6 +252,10 @@ public Object getToType() { return String.class; } + + public boolean isAsync() { + return false; + } }; IValidator vowelValidator = new IValidator() { public IStatus validate(Object value) { Index: src/org/eclipse/jface/examples/databinding/snippets/Snippet022AsyncUpdate.java =================================================================== RCS file: src/org/eclipse/jface/examples/databinding/snippets/Snippet022AsyncUpdate.java diff -N src/org/eclipse/jface/examples/databinding/snippets/Snippet022AsyncUpdate.java --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ src/org/eclipse/jface/examples/databinding/snippets/Snippet022AsyncUpdate.java 1 Jan 1970 00:00:00 -0000 @@ -0,0 +1,320 @@ +/******************************************************************************* + * Copyright (c) 2008 Ovidio Mallo and others. + * All rights reserved. This program and the accompanying materials + * are made available under the terms of the Eclipse Public License v1.0 + * which accompanies this distribution, and is available at + * http://www.eclipse.org/legal/epl-v10.html + * + * Contributors: + * Ovidio Mallo - initial API and implementation (bug 233191) + ******************************************************************************/ + +package org.eclipse.jface.examples.databinding.snippets; + +import java.util.Random; + +import org.eclipse.core.databinding.DataBindingContext; +import org.eclipse.core.databinding.UpdateListStrategy; +import org.eclipse.core.databinding.UpdateValueStrategy; +import org.eclipse.core.databinding.conversion.Converter; +import org.eclipse.core.databinding.conversion.IConverter; +import org.eclipse.core.databinding.observable.Realm; +import org.eclipse.core.databinding.observable.list.IObservableList; +import org.eclipse.core.databinding.observable.list.WritableList; +import org.eclipse.core.databinding.observable.value.IObservableValue; +import org.eclipse.core.databinding.observable.value.WritableValue; +import org.eclipse.jface.databinding.swt.SWTObservables; +import org.eclipse.jface.databinding.viewers.ObservableListContentProvider; +import org.eclipse.jface.layout.GridDataFactory; +import org.eclipse.jface.layout.GridLayoutFactory; +import org.eclipse.jface.viewers.IStructuredSelection; +import org.eclipse.jface.viewers.LabelProvider; +import org.eclipse.jface.viewers.ListViewer; +import org.eclipse.swt.SWT; +import org.eclipse.swt.events.KeyAdapter; +import org.eclipse.swt.events.KeyEvent; +import org.eclipse.swt.events.ModifyEvent; +import org.eclipse.swt.events.ModifyListener; +import org.eclipse.swt.events.SelectionAdapter; +import org.eclipse.swt.events.SelectionEvent; +import org.eclipse.swt.widgets.Button; +import org.eclipse.swt.widgets.Composite; +import org.eclipse.swt.widgets.Display; +import org.eclipse.swt.widgets.Group; +import org.eclipse.swt.widgets.Label; +import org.eclipse.swt.widgets.Shell; +import org.eclipse.swt.widgets.Spinner; +import org.eclipse.swt.widgets.Text; + +/** + * Snippet that demonstrates the usage of asynchronous bindings by defining an + * asynchronous converter which introduces some artificial delay during + * conversion. The example allows to manually change the target or model of a + * ValueBinding/ListBinding and to see how the counterpart gets updated + * asynchronously. In addition, automatic updates of the target and/or model can + * be triggered. + */ +public class Snippet022AsyncUpdate { + + private int updateDelay = 1000; + + private boolean randomizeUpdateDelay = true; + + private DataBindingContext dbc; + + private WritableValue valueTarget; + + private WritableValue valueModel; + + private WritableList listTarget; + + private WritableList listModel; + + public void createControl(Composite parent) { + dbc = new DataBindingContext(); + + parent.setLayout(GridLayoutFactory.fillDefaults().margins(5, 5) + .spacing(15, 10).create()); + + createSettingsGroup(parent); + createValueBindingGroup(parent); + createListBindingGroup(parent); + createAutomaticUpdatesGroup(parent); + } + + private void createSettingsGroup(Composite parent) { + Group group = new Group(parent, SWT.NONE); + group.setText("Settings"); + group.setLayout(GridLayoutFactory.fillDefaults().numColumns(2).margins( + 5, 7).spacing(15, 10).create()); + GridDataFactory.fillDefaults().grab(true, false).applyTo(group); + + new Label(group, SWT.NONE).setText("Update delay"); + final Spinner updateDelaySpinner = new Spinner(group, SWT.BORDER); + GridDataFactory.fillDefaults().grab(true, false).applyTo( + updateDelaySpinner); + updateDelaySpinner.setMinimum(1); + updateDelaySpinner.setMaximum(Integer.MAX_VALUE); + updateDelaySpinner.setSelection(updateDelay); + updateDelaySpinner.addModifyListener(new ModifyListener() { + public void modifyText(ModifyEvent e) { + updateDelay = updateDelaySpinner.getSelection(); + } + }); + + final Button randomizeUpdateDelayButton = new Button(group, SWT.CHECK); + randomizeUpdateDelayButton.setText("Randomize update delay"); + GridDataFactory.fillDefaults().grab(true, false).span(2, 1).applyTo( + randomizeUpdateDelayButton); + randomizeUpdateDelayButton.setSelection(randomizeUpdateDelay); + randomizeUpdateDelayButton.addSelectionListener(new SelectionAdapter() { + public void widgetSelected(SelectionEvent e) { + randomizeUpdateDelay = randomizeUpdateDelayButton + .getSelection(); + } + }); + } + + private void createValueBindingGroup(Composite parent) { + Group group = new Group(parent, SWT.NONE); + group.setText("Value Binding"); + group.setLayout(GridLayoutFactory.fillDefaults().numColumns(2).margins( + 5, 7).spacing(15, 10).create()); + GridDataFactory.fillDefaults().grab(true, false).applyTo(group); + + valueTarget = WritableValue.withValueType(String.class); + createValueComponent(group, "Target", valueTarget); + + valueModel = WritableValue.withValueType(String.class); + createValueComponent(group, "Model", valueModel); + + dbc.bindValue(valueTarget, valueModel, new UpdateValueStrategy() + .setConverter(asyncConverter()), new UpdateValueStrategy() + .setConverter(asyncConverter())); + } + + private void createValueComponent(Composite parent, String title, + IObservableValue observableValue) { + new Label(parent, SWT.NONE).setText(title); + Text text = new Text(parent, SWT.BORDER); + GridDataFactory.fillDefaults().grab(true, false).applyTo(text); + + dbc.bindValue(SWTObservables.observeText(text, SWT.Modify), + observableValue, null, null); + } + + private void createListBindingGroup(Composite parent) { + Group group = new Group(parent, SWT.NONE); + group.setText("List Binding"); + group.setLayout(GridLayoutFactory.fillDefaults().numColumns(2).margins( + 5, 7).spacing(15, 10).create()); + GridDataFactory.fillDefaults().grab(true, true).applyTo(group); + + listTarget = WritableList.withElementType(String.class); + createListComponent(group, "Target", listTarget); + + listModel = WritableList.withElementType(String.class); + createListComponent(group, "Model", listModel); + + dbc.bindList(listTarget, listModel, new UpdateListStrategy() + .setConverter(asyncConverter()), new UpdateListStrategy() + .setConverter(asyncConverter())); + } + + private void createListComponent(Composite parent, String title, + final IObservableList observableList) { + new Label(parent, SWT.NONE).setText(title); + final Text targetText = new Text(parent, SWT.BORDER); + GridDataFactory.fillDefaults().grab(true, false).applyTo(targetText); + targetText.addKeyListener(new KeyAdapter() { + public void keyPressed(KeyEvent e) { + if (e.keyCode == SWT.CR) { + observableList.add(targetText.getText()); + targetText.selectAll(); + } + } + }); + new Label(parent, SWT.NONE); + final ListViewer targetList = new ListViewer(parent, SWT.BORDER + | SWT.MULTI | SWT.V_SCROLL); + GridDataFactory.fillDefaults().minSize(SWT.DEFAULT, 150).grab(true, + true).applyTo(targetList.getList()); + targetList.setContentProvider(new ObservableListContentProvider()); + targetList.setLabelProvider(new LabelProvider()); + targetList.setInput(observableList); + targetList.getList().addKeyListener(new KeyAdapter() { + public void keyPressed(KeyEvent e) { + if (e.keyCode == SWT.DEL) { + IStructuredSelection selection = (IStructuredSelection) targetList + .getSelection(); + observableList.removeAll(selection.toList()); + } + } + }); + } + + private void createAutomaticUpdatesGroup(Composite parent) { + Group group = new Group(parent, SWT.NONE); + group.setText("Automatic Updates"); + group.setLayout(GridLayoutFactory.fillDefaults().numColumns(3) + .equalWidth(true).margins(5, 5).create()); + GridDataFactory.fillDefaults().grab(true, false).applyTo(group); + + Button targetButton = new Button(group, SWT.PUSH); + targetButton.setText("Target"); + GridDataFactory.fillDefaults().align(SWT.FILL, SWT.CENTER).grab(true, + false).applyTo(targetButton); + targetButton.addSelectionListener(new SelectionAdapter() { + public void widgetSelected(SelectionEvent e) { + valueModel.setValue(""); + listTarget.clear(); + for (int i = 0; i < 10; i++) { + String value = String.valueOf(i); + valueTarget.setValue(value); + listTarget.add(value); + + Display.getCurrent().update(); + sleep(100); + } + } + }); + + Button modelButton = new Button(group, SWT.PUSH); + modelButton.setText("Model"); + GridDataFactory.fillDefaults().align(SWT.FILL, SWT.CENTER).grab(true, + false).applyTo(modelButton); + modelButton.addSelectionListener(new SelectionAdapter() { + public void widgetSelected(SelectionEvent e) { + valueTarget.setValue(""); + listModel.clear(); + for (int i = 0; i < 10; i++) { + String value = String.valueOf(i); + valueModel.setValue(value); + listModel.add(value); + + Display.getCurrent().update(); + sleep(100); + } + } + }); + + Button twowayButton = new Button(group, SWT.PUSH); + twowayButton.setText("Twoway"); + GridDataFactory.fillDefaults().align(SWT.FILL, SWT.CENTER).grab(true, + false).applyTo(twowayButton); + twowayButton.addSelectionListener(new SelectionAdapter() { + public void widgetSelected(SelectionEvent e) { + valueTarget.setValue(""); + valueModel.setValue(""); + listTarget.clear(); + listModel.clear(); + for (int i = 0; i < 10; i++) { + String value = String.valueOf(i); + if (i % 2 == 0) { + valueTarget.setValue(value); + listTarget.add(value); + } else { + valueModel.setValue(value); + listModel.add(value); + } + + Display.getCurrent().update(); + sleep(100); + } + } + }); + } + + private IConverter asyncConverter() { + return new Converter(null, null) { + private final Random random = new Random(System.currentTimeMillis()); + + public Object convert(Object fromObject) { + if (randomizeUpdateDelay) { + sleep(random.nextInt(updateDelay)); + } else { + sleep(updateDelay); + } + + return fromObject; + } + + public boolean isAsync() { + return true; + } + }; + } + + private static void sleep(long millis) { + try { + Thread.sleep(millis); + } catch (InterruptedException e1) { + // go ahead + } + } + + public static void main(String[] args) { + Display display = new Display(); + + Realm.runWithDefault(SWTObservables.getRealm(display), new Runnable() { + public void run() { + Display display = Display.getCurrent(); + final Shell shell = new Shell(display); + shell.setText("Asynchronous Bindings"); + new Snippet022AsyncUpdate().createControl(shell); + + shell.setMinimumSize(shell.computeSize(350, SWT.DEFAULT)); + shell.pack(); + shell.open(); + + // The SWT event loop + while (!shell.isDisposed()) { + if (!display.readAndDispatch()) { + display.sleep(); + } + } + display.dispose(); + } + }); + } +} Index: src/org/eclipse/jface/examples/databinding/snippets/Snippet023AsyncUpdateWizard.java =================================================================== RCS file: src/org/eclipse/jface/examples/databinding/snippets/Snippet023AsyncUpdateWizard.java diff -N src/org/eclipse/jface/examples/databinding/snippets/Snippet023AsyncUpdateWizard.java --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ src/org/eclipse/jface/examples/databinding/snippets/Snippet023AsyncUpdateWizard.java 1 Jan 1970 00:00:00 -0000 @@ -0,0 +1,225 @@ +/******************************************************************************* + * Copyright (c) 2008 Ovidio Mallo and others. + * All rights reserved. This program and the accompanying materials + * are made available under the terms of the Eclipse Public License v1.0 + * which accompanies this distribution, and is available at + * http://www.eclipse.org/legal/epl-v10.html + * + * Contributors: + * Ovidio Mallo - initial API and implementation (bug 233191) + ******************************************************************************/ + +package org.eclipse.jface.examples.databinding.snippets; + +import java.util.Random; + +import org.eclipse.core.databinding.DataBindingContext; +import org.eclipse.core.databinding.UpdateValueStrategy; +import org.eclipse.core.databinding.observable.Realm; +import org.eclipse.core.databinding.observable.value.WritableValue; +import org.eclipse.core.databinding.validation.IValidator2; +import org.eclipse.core.databinding.validation.MultiValidator; +import org.eclipse.core.databinding.validation.ValidationStatus; +import org.eclipse.core.runtime.IProgressMonitor; +import org.eclipse.core.runtime.IStatus; +import org.eclipse.core.runtime.Status; +import org.eclipse.core.runtime.jobs.Job; +import org.eclipse.jface.databinding.swt.SWTObservables; +import org.eclipse.jface.databinding.wizard.WizardPageSupport; +import org.eclipse.jface.examples.databinding.decoration.ControlDecorator; +import org.eclipse.jface.layout.GridDataFactory; +import org.eclipse.jface.layout.GridLayoutFactory; +import org.eclipse.jface.resource.ImageDescriptor; +import org.eclipse.jface.util.Util; +import org.eclipse.jface.wizard.Wizard; +import org.eclipse.jface.wizard.WizardDialog; +import org.eclipse.jface.wizard.WizardPage; +import org.eclipse.swt.SWT; +import org.eclipse.swt.graphics.Image; +import org.eclipse.swt.widgets.Composite; +import org.eclipse.swt.widgets.Display; +import org.eclipse.swt.widgets.Label; +import org.eclipse.swt.widgets.Shell; +import org.eclipse.swt.widgets.Text; + +/** + * Snippet that demonstrates the usage of asynchronous binding as well as cross + * field validations in the context of a wizard page. The example mainly tries + * to illustrate how the WizardPageSupport class tracks the staleness state of + * all the ValidationStatusProviders of the given data binding context, thus + * waiting for pending validations before allowing the user to flip to the next + * wizard page. + */ +public class Snippet023AsyncUpdateWizard { + + private static class AsyncBindingWizardPage extends WizardPage { + + public AsyncBindingWizardPage() { + super("Asynchronous Bindings", "Asynchronous Bindings", + ImageDescriptor.createFromImage(new Image(Display + .getCurrent(), 16, 16))); + } + + public void createControl(Composite parent) { + Composite container = new Composite(parent, SWT.NONE); + container.setLayout(GridLayoutFactory.fillDefaults().numColumns(2) + .margins(5, 5).spacing(15, 10).create()); + GridDataFactory.fillDefaults().grab(true, false).applyTo(container); + + final DataBindingContext dbc = new DataBindingContext(); + + // We use a control decorator to better illustrate when validations + // are pending on the individual bindings. + ControlDecorator controlDecorator = new ControlDecorator(); + controlDecorator.addDbc(dbc); + + WizardPageSupport.create(this, dbc); + + new Label(container, SWT.NONE).setText("Value 1"); + Text v1Text = new Text(container, SWT.BORDER); + GridDataFactory.fillDefaults().grab(true, false).applyTo(v1Text); + + final WritableValue value1 = new WritableValue(); + dbc.bindValue(SWTObservables.observeText(v1Text, SWT.Modify), + value1, asyncStrategy(), null); + + new Label(container, SWT.NONE).setText("Value 2"); + Text v2Text = new Text(container, SWT.BORDER); + GridDataFactory.fillDefaults().grab(true, false).applyTo(v2Text); + + final WritableValue value2 = new WritableValue(); + dbc.bindValue(SWTObservables.observeText(v2Text, SWT.Modify), + value2, asyncStrategy(), null); + + // Define the cross field validator. + MultiValidator multiValidator = new MultiValidator() { + private Job validationJob; + + protected IStatus validate() { + // Cancel any previous job when re-evaluating the + // validation. + if (validationJob != null) { + validationJob.cancel(); + } + + // The observables cannot be accessed from within a + // different thread so we must extract their containing + // values at this point. + final Object v1 = value1.getValue(); + final Object v2 = value2.getValue(); + validationJob = new Job("Equality validation") { + protected IStatus run(final IProgressMonitor monitor) { + // Do the actual validation. + final IStatus validation; + if (!Util.equals(v1, v2)) { + validation = ValidationStatus + .error("The two values must be equal."); + } else { + validation = ValidationStatus.ok(); + } + + // Take it easy :-). + try { + Thread.sleep(1000); + } catch (InterruptedException e) { + // go ahead + } + + // Notify the MultiValidator about the completed + // validation. This must be done from within the + // MultiValidator's realm (here the validation + // realm). + dbc.getValidationRealm().exec(new Runnable() { + public void run() { + // Check if this validation has been + // canceled in the meanwhile. + if (!monitor.isCanceled()) { + exitStale(validation); + } + } + }); + + return Status.OK_STATUS; + } + }; + validationJob.setSystem(true); + validationJob.schedule(); + + // Notify the MultiValidator about the validation being + // performed asynchronously. + enterStale(); + + // Return a temporary validation to be shown to the user + // while the actual validation has not completed. + return ValidationStatus + .info("Cross field validation is pending..."); + } + + public void dispose() { + if (validationJob != null) { + validationJob.cancel(); + } + + super.dispose(); + } + }; + dbc.addValidationStatusProvider(multiValidator); + + setControl(container); + } + } + + private static UpdateValueStrategy asyncStrategy() { + IValidator2 asyncValidator = new IValidator2() { + private final Random random = new Random(System.currentTimeMillis()); + + public IStatus validate(Object value) { + try { + Thread.sleep(random.nextInt(1000)); + } catch (InterruptedException e) { + // go ahead + } + + String input = (String) value; + if (input != null) { + if (input.length() > 15) { + return ValidationStatus.error("Input is too long."); + } + } + + return ValidationStatus.ok(); + } + + public boolean isAsync() { + return true; + } + }; + + return new UpdateValueStrategy().setBeforeSetValidator(asyncValidator); + } + + public static void main(String[] args) { + Display display = new Display(); + + Realm.runWithDefault(SWTObservables.getRealm(display), new Runnable() { + public void run() { + Display display = Display.getCurrent(); + final Shell shell = new Shell(display); + shell.setText("Asynchronous Bindings"); + + Wizard wizard = new Wizard() { + public boolean performFinish() { + return true; + } + }; + wizard.setWindowTitle("Asynchronous Bindings"); + wizard.addPage(new AsyncBindingWizardPage()); + + WizardDialog dialog = new WizardDialog(shell, wizard); + dialog.open(); + + display.dispose(); + } + }); + } +} Index: src/org/eclipse/jface/examples/databinding/decoration/ControlDecorator.java =================================================================== RCS file: src/org/eclipse/jface/examples/databinding/decoration/ControlDecorator.java diff -N src/org/eclipse/jface/examples/databinding/decoration/ControlDecorator.java --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ src/org/eclipse/jface/examples/databinding/decoration/ControlDecorator.java 1 Jan 1970 00:00:00 -0000 @@ -0,0 +1,153 @@ +/******************************************************************************* + * Copyright (c) 2008 Ovidio Mallo and others. + * All rights reserved. This program and the accompanying materials + * are made available under the terms of the Eclipse Public License v1.0 + * which accompanies this distribution, and is available at + * http://www.eclipse.org/legal/epl-v10.html + * + * Contributors: + * Ovidio Mallo - initial API and implementation + ******************************************************************************/ + +package org.eclipse.jface.examples.databinding.decoration; + +import java.util.HashMap; +import java.util.Iterator; +import java.util.Map; + +import org.eclipse.core.databinding.Binding; +import org.eclipse.core.databinding.DataBindingContext; +import org.eclipse.core.databinding.observable.IStaleListener; +import org.eclipse.core.databinding.observable.StaleEvent; +import org.eclipse.core.databinding.observable.list.IListChangeListener; +import org.eclipse.core.databinding.observable.list.IObservableList; +import org.eclipse.core.databinding.observable.list.ListChangeEvent; +import org.eclipse.core.databinding.observable.list.ListDiff; +import org.eclipse.core.databinding.observable.list.ListDiffEntry; +import org.eclipse.core.databinding.observable.value.IObservableValue; +import org.eclipse.core.databinding.observable.value.IValueChangeListener; +import org.eclipse.core.databinding.observable.value.ValueChangeEvent; +import org.eclipse.core.runtime.IStatus; +import org.eclipse.jface.databinding.swt.ISWTObservable; +import org.eclipse.jface.fieldassist.ControlDecoration; +import org.eclipse.jface.fieldassist.FieldDecorationRegistry; +import org.eclipse.swt.SWT; +import org.eclipse.swt.graphics.Image; +import org.eclipse.swt.widgets.Control; + +/** + * Simple control decorator which visualizes the validation status of a binding + * on a control assuming the binding's target observable is of type + * {@link ISWTObservable} and {@link ISWTObservable#getWidget()} returns a + * {@link Control} instance to be decorated. In addition, the staleness state of + * a binding's validation status observable is also visualized on the control. + */ +public class ControlDecorator { + + private static final int DECORATION_POSITION = SWT.LEFT | SWT.TOP; + + private final Map bindingToDecorationMap = new HashMap(); + + private IListChangeListener bindingsListener = new IListChangeListener() { + public void handleListChange(ListChangeEvent event) { + ListDiff diff = event.diff; + ListDiffEntry[] differences = diff.getDifferences(); + for (int i = 0; i < differences.length; i++) { + ListDiffEntry listDiffEntry = differences[i]; + Binding binding = (Binding) listDiffEntry.getElement(); + if (listDiffEntry.isAddition()) { + addBinding(binding); + } else { + removeBinding(binding); + } + } + } + }; + + public void addDbc(DataBindingContext dbc) { + IObservableList bindings = dbc.getBindings(); + for (Iterator iterator = bindings.iterator(); iterator.hasNext();) { + Binding binding = (Binding) iterator.next(); + addBinding(binding); + } + bindings.addListChangeListener(bindingsListener); + } + + private void addBinding(final Binding binding) { + if (binding.getTarget() instanceof ISWTObservable) { + ISWTObservable target = (ISWTObservable) binding.getTarget(); + if (target.getWidget() instanceof Control) { + Control control = (Control) target.getWidget(); + final ControlDecoration decoration = new ControlDecoration( + control, DECORATION_POSITION); + + binding.getValidationStatus().addValueChangeListener( + new IValueChangeListener() { + public void handleValueChange(ValueChangeEvent event) { + updateDecoration(decoration, binding); + } + }); + + binding.getValidationStatus().addStaleListener( + new IStaleListener() { + public void handleStale(StaleEvent staleEvent) { + updateDecoration(decoration, binding); + } + }); + + bindingToDecorationMap.put(binding, decoration); + updateDecoration(decoration, binding); + } + } + } + + private void removeBinding(Binding binding) { + ControlDecoration decoration = (ControlDecoration) bindingToDecorationMap + .get(binding); + if (decoration != null) { + decoration.hide(); + decoration.setDescriptionText(null); + + bindingToDecorationMap.remove(binding); + } + } + + private void updateDecoration(ControlDecoration decoration, Binding binding) { + IObservableValue validation = binding.getValidationStatus(); + if (validation.isStale()) { + showPendingUpdate(decoration); + return; + } + + IStatus validationStatus = (IStatus) validation.getValue(); + if (validationStatus.isOK()) { + decoration.hide(); + } else { + decoration.show(); + decoration.setImage(getStatusImage(validationStatus)); + decoration.setDescriptionText(validationStatus.getMessage()); + } + } + + private void showPendingUpdate(final ControlDecoration decoration) { + decoration.show(); + decoration.setImage(getImage(FieldDecorationRegistry.DEC_INFORMATION)); + decoration.setDescriptionText("Pending update..."); + } + + private Image getImage(String key) { + return FieldDecorationRegistry.getDefault().getFieldDecoration(key) + .getImage(); + } + + private Image getStatusImage(IStatus status) { + if (status.matches(IStatus.ERROR)) { + return getImage(FieldDecorationRegistry.DEC_ERROR); + } else if (status.matches(IStatus.WARNING)) { + return getImage(FieldDecorationRegistry.DEC_WARNING); + } else if (status.matches(IStatus.INFO)) { + return getImage(FieldDecorationRegistry.DEC_INFORMATION); + } + return null; + } +}