| /******************************************************************************* |
| * Copyright (c) 2007, 2009 IBM Corporation 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: |
| * IBM Corporation - initial API and implementation |
| * Matthew Hall - bugs 220700, 271148, 278550 |
| *******************************************************************************/ |
| |
| package org.eclipse.core.databinding; |
| |
| import org.eclipse.core.databinding.observable.ObservableTracker; |
| 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.databinding.observable.value.WritableValue; |
| import org.eclipse.core.databinding.util.Policy; |
| import org.eclipse.core.internal.databinding.BindingStatus; |
| import org.eclipse.core.internal.databinding.Util; |
| import org.eclipse.core.runtime.IStatus; |
| import org.eclipse.core.runtime.MultiStatus; |
| import org.eclipse.core.runtime.Status; |
| |
| /** |
| * @since 1.0 |
| * |
| */ |
| class ValueBinding extends Binding { |
| private final UpdateValueStrategy targetToModel; |
| private final UpdateValueStrategy modelToTarget; |
| private WritableValue validationStatusObservable; |
| private IObservableValue target; |
| private IObservableValue model; |
| |
| private boolean updatingTarget; |
| private boolean updatingModel; |
| private IValueChangeListener targetChangeListener = new IValueChangeListener() { |
| public void handleValueChange(ValueChangeEvent event) { |
| if (!updatingTarget |
| && !Util.equals(event.diff.getOldValue(), event.diff |
| .getNewValue())) { |
| doUpdate(target, model, targetToModel, false, false); |
| } |
| } |
| }; |
| private IValueChangeListener modelChangeListener = new IValueChangeListener() { |
| public void handleValueChange(ValueChangeEvent event) { |
| if (!updatingModel |
| && !Util.equals(event.diff.getOldValue(), event.diff |
| .getNewValue())) { |
| doUpdate(model, target, modelToTarget, false, false); |
| } |
| } |
| }; |
| |
| /** |
| * @param targetObservableValue |
| * @param modelObservableValue |
| * @param targetToModel |
| * @param modelToTarget |
| */ |
| public ValueBinding(IObservableValue targetObservableValue, |
| IObservableValue modelObservableValue, |
| UpdateValueStrategy targetToModel, UpdateValueStrategy modelToTarget) { |
| super(targetObservableValue, modelObservableValue); |
| this.target = targetObservableValue; |
| this.model = modelObservableValue; |
| this.targetToModel = targetToModel; |
| this.modelToTarget = modelToTarget; |
| if ((targetToModel.getUpdatePolicy() & (UpdateValueStrategy.POLICY_CONVERT | UpdateValueStrategy.POLICY_UPDATE)) != 0) { |
| target.addValueChangeListener(targetChangeListener); |
| } else { |
| targetChangeListener = null; |
| } |
| if ((modelToTarget.getUpdatePolicy() & (UpdateValueStrategy.POLICY_CONVERT | UpdateValueStrategy.POLICY_UPDATE)) != 0) { |
| model.addValueChangeListener(modelChangeListener); |
| } else { |
| modelChangeListener = null; |
| } |
| } |
| |
| protected void preInit() { |
| ObservableTracker.setIgnore(true); |
| try { |
| validationStatusObservable = new WritableValue(context |
| .getValidationRealm(), Status.OK_STATUS, IStatus.class); |
| } finally { |
| ObservableTracker.setIgnore(false); |
| } |
| } |
| |
| protected void postInit() { |
| if (modelToTarget.getUpdatePolicy() == UpdateValueStrategy.POLICY_UPDATE) { |
| updateModelToTarget(); |
| } else if (modelToTarget.getUpdatePolicy() == UpdateValueStrategy.POLICY_CONVERT) { |
| validateModelToTarget(); |
| } |
| if (targetToModel.getUpdatePolicy() == UpdateValueStrategy.POLICY_UPDATE |
| || targetToModel.getUpdatePolicy() == UpdateValueStrategy.POLICY_CONVERT) { |
| validateTargetToModel(); |
| } |
| } |
| |
| public IObservableValue getValidationStatus() { |
| return validationStatusObservable; |
| } |
| |
| public void updateTargetToModel() { |
| doUpdate(target, model, targetToModel, true, false); |
| } |
| |
| public void updateModelToTarget() { |
| doUpdate(model, target, modelToTarget, true, false); |
| } |
| |
| /** |
| * Incorporates the provided <code>newStats</code> into the |
| * <code>multieStatus</code>. |
| * |
| * @param multiStatus |
| * @param newStatus |
| * @return <code>true</code> if the update should proceed |
| */ |
| /* package */boolean mergeStatus(MultiStatus multiStatus, IStatus newStatus) { |
| if (!newStatus.isOK()) { |
| multiStatus.add(newStatus); |
| return multiStatus.getSeverity() < IStatus.ERROR; |
| } |
| return true; |
| } |
| |
| /* |
| * This method may be moved to UpdateValueStrategy in the future if clients |
| * need more control over how the source value is copied to the destination |
| * observable. |
| */ |
| private void doUpdate(final IObservableValue source, |
| final IObservableValue destination, |
| final UpdateValueStrategy updateValueStrategy, |
| final boolean explicit, final boolean validateOnly) { |
| |
| final int policy = updateValueStrategy.getUpdatePolicy(); |
| if (policy == UpdateValueStrategy.POLICY_NEVER) |
| return; |
| if (policy == UpdateValueStrategy.POLICY_ON_REQUEST && !explicit) |
| return; |
| |
| 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; |
| } |
| setValidationStatus(multiStatus); |
| } |
| } |
| }); |
| } 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); |
| } |
| |
| } |
| } |
| }); |
| } |
| |
| public void validateModelToTarget() { |
| doUpdate(model, target, modelToTarget, true, true); |
| } |
| |
| public void validateTargetToModel() { |
| doUpdate(target, model, targetToModel, true, true); |
| } |
| |
| private void setValidationStatus(final IStatus status) { |
| validationStatusObservable.getRealm().exec(new Runnable() { |
| public void run() { |
| validationStatusObservable.setValue(status); |
| } |
| }); |
| } |
| |
| public void dispose() { |
| if (targetChangeListener != null) { |
| target.removeValueChangeListener(targetChangeListener); |
| targetChangeListener = null; |
| } |
| if (modelChangeListener != null) { |
| model.removeValueChangeListener(modelChangeListener); |
| modelChangeListener = null; |
| } |
| target = null; |
| model = null; |
| super.dispose(); |
| } |
| |
| } |