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annotate org.eclipse.core.databinding/src/org/eclipse/core/databinding/validation/MultiValidator.d @ 88:9e0ab372d5d8
Revert from TypeInfo/ClassInfo to java.lang.Class
| author | Frank Benoit <benoit@tionex.de> |
|---|---|
| date | Sun, 19 Apr 2009 11:10:09 +0200 |
| parents | 6be48cf9f95c |
| children |
| rev | line source |
|---|---|
| 78 | 1 /******************************************************************************* |
| 2 * Copyright (c) 2008 Matthew Hall and others. | |
| 3 * All rights reserved. This program and the accompanying materials | |
| 4 * are made available under the terms of the Eclipse Public License v1.0 | |
| 5 * which accompanies this distribution, and is available at | |
| 6 * http://www.eclipse.org/legal/epl-v10.html | |
| 7 * | |
| 8 * Contributors: | |
| 9 * Matthew Hall - initial API and implementation (bug 218269) | |
| 10 * Boris Bokowski - bug 218269 | |
| 11 ******************************************************************************/ | |
| 12 | |
| 13 module org.eclipse.core.databinding.validation.MultiValidator; | |
| 81 | 14 import org.eclipse.core.databinding.validation.ValidationStatus; |
| 78 | 15 |
| 16 import java.lang.all; | |
| 17 | |
| 18 import java.util.ArrayList; | |
| 19 import java.util.Arrays; | |
| 20 | |
| 21 import org.eclipse.core.databinding.ValidationStatusProvider; | |
| 22 import org.eclipse.core.databinding.observable.ChangeEvent; | |
| 23 import org.eclipse.core.databinding.observable.IChangeListener; | |
| 24 import org.eclipse.core.databinding.observable.IObservable; | |
| 25 import org.eclipse.core.databinding.observable.ObservableTracker; | |
| 26 import org.eclipse.core.databinding.observable.Observables; | |
| 27 import org.eclipse.core.databinding.observable.Realm; | |
| 28 import org.eclipse.core.databinding.observable.list.IListChangeListener; | |
| 29 import org.eclipse.core.databinding.observable.list.IObservableList; | |
| 30 import org.eclipse.core.databinding.observable.list.ListChangeEvent; | |
| 31 import org.eclipse.core.databinding.observable.list.ListDiffVisitor; | |
| 32 import org.eclipse.core.databinding.observable.list.WritableList; | |
| 33 import org.eclipse.core.databinding.observable.map.IObservableMap; | |
| 34 import org.eclipse.core.databinding.observable.set.IObservableSet; | |
| 35 import org.eclipse.core.databinding.observable.value.IObservableValue; | |
| 36 import org.eclipse.core.databinding.observable.value.WritableValue; | |
| 37 import org.eclipse.core.internal.databinding.observable.ValidatedObservableList; | |
| 38 import org.eclipse.core.internal.databinding.observable.ValidatedObservableMap; | |
| 39 import org.eclipse.core.internal.databinding.observable.ValidatedObservableSet; | |
| 40 import org.eclipse.core.internal.databinding.observable.ValidatedObservableValue; | |
| 41 import org.eclipse.core.runtime.Assert; | |
| 42 import org.eclipse.core.runtime.IStatus; | |
| 43 | |
| 44 /** | |
| 45 * A validator for cross-constraints between observables. | |
| 46 * | |
| 47 * <p> | |
| 48 * Some practical examples of cross-constraints: | |
| 49 * <ul> | |
| 50 * <li>A start date cannot be later than an end date | |
| 51 * <li>A list of percentages should add up to 100% | |
| 52 * </ul> | |
| 53 * <p> | |
| 54 * Example: require two integer fields to contain either both even or both odd | |
| 55 * numbers. | |
| 56 * | |
| 57 * <pre> | |
| 58 * DataBindingContext dbc = new DataBindingContext(); | |
| 59 * | |
| 60 * IObservableValue target0 = SWTObservables.observeText(text0, SWT.Modify); | |
| 61 * IObservableValue target1 = SWTObservables.observeText(text1, SWT.Modify); | |
| 62 * | |
| 63 * // Binding in two stages (from target to middle, then from middle to model) | |
| 64 * // simplifies the validation logic. Using the middle observables saves | |
| 65 * // the trouble of converting the target values cast(Strings) to the model type | |
| 66 * // (integers) manually during validation. | |
| 67 * final IObservableValue middle0 = new WritableValue(null, Integer.TYPE); | |
| 68 * final IObservableValue middle1 = new WritableValue(null, Integer.TYPE); | |
| 69 * dbc.bind(target0, middle0, null, null); | |
| 70 * dbc.bind(target1, middle1, null, null); | |
| 71 * | |
| 72 * // Create the multi-validator | |
| 73 * MultiValidator validator = new class() MultiValidator { | |
| 74 * protected IStatus validate() { | |
| 75 * // Calculate the validation status | |
| 76 * Integer value0 = cast(Integer) middle0.getValue(); | |
| 77 * Integer value1 = cast(Integer) middle1.getValue(); | |
| 78 * if (Math.abs(value0.intValue()) % 2 !is Math.abs(value1.intValue()) % 2) | |
| 79 * return ValidationStatus | |
| 80 * .error("Values must be both even or both odd"); | |
| 81 * return ValidationStatus.ok(); | |
| 82 * } | |
| 83 * }; | |
| 84 * dbc.addValidationStatusProvider(validator); | |
| 85 * | |
| 86 * // Bind the middle observables to the model observables. | |
| 87 * IObservableValue model0 = new WritableValue(new Integer(2), Integer.TYPE); | |
| 88 * IObservableValue model1 = new WritableValue(new Integer(4), Integer.TYPE); | |
| 89 * dbc.bind(middle0, model0, null, null); | |
| 90 * dbc.bind(middle1, model1, null, null); | |
| 91 * </pre> | |
| 92 * | |
| 93 * <p> | |
| 94 * MultiValidator can also prevent invalid data from being copied to model. This | |
| 95 * is done by wrapping each target observable in a validated observable, and | |
| 96 * then binding the validated observable to the model. | |
| 97 * | |
| 98 * <pre> | |
| 99 * | |
| 100 * ... | |
| 101 * | |
| 102 * // Validated observables do not change value until the validator passes. | |
| 103 * IObservableValue validated0 = validator.observeValidatedValue(middle0); | |
| 104 * IObservableValue validated1 = validator.observeValidatedValue(middle1); | |
| 105 * IObservableValue model0 = new WritableValue(new Integer(2), Integer.TYPE); | |
| 106 * IObservableValue model1 = new WritableValue(new Integer(4), Integer.TYPE); | |
| 107 * // Bind to the validated value, not the middle/target | |
| 108 * dbc.bind(validated0, model0, null, null); | |
| 109 * dbc.bind(validated1, model1, null, null); | |
| 110 * </pre> | |
| 111 * | |
| 112 * Note: No guarantee is made as to the order of updates when multiple validated | |
| 113 * observables change value at once (i.e. multiple updates pending when the | |
| 114 * status becomes valid). Therefore the model may be in an invalid state after | |
| 115 * the first but before the last pending update. | |
| 116 * | |
| 117 * @since 1.1 | |
| 118 */ | |
| 119 public abstract class MultiValidator : ValidationStatusProvider { | |
| 120 private Realm realm; | |
| 121 private IObservableValue validationStatus; | |
| 122 private IObservableValue unmodifiableValidationStatus; | |
| 123 private WritableList targets; | |
| 124 private IObservableList unmodifiableTargets; | |
| 125 private IObservableList models; | |
| 126 | |
| 85 | 127 IListChangeListener targetsListener; |
| 128 class TargetsListener : IListChangeListener { | |
| 78 | 129 public void handleListChange(ListChangeEvent event) { |
| 130 event.diff.accept(new class() ListDiffVisitor { | |
| 131 public void handleAdd(int index, Object element) { | |
| 132 (cast(IObservable) element) | |
| 133 .addChangeListener(dependencyListener); | |
| 134 } | |
| 135 | |
| 136 public void handleRemove(int index, Object element) { | |
| 137 (cast(IObservable) element) | |
| 138 .removeChangeListener(dependencyListener); | |
| 139 } | |
| 140 }); | |
| 141 } | |
| 142 }; | |
| 143 | |
| 85 | 144 private IChangeListener dependencyListener; |
| 145 class DependencyListener : IChangeListener { | |
| 78 | 146 public void handleChange(ChangeEvent event) { |
| 147 revalidate(); | |
| 148 } | |
| 149 }; | |
| 150 | |
| 151 /** | |
| 152 * Constructs a MultiValidator on the default realm. | |
| 153 */ | |
| 154 public this() { | |
| 155 this(Realm.getDefault()); | |
| 156 } | |
| 157 | |
| 158 /** | |
| 159 * Constructs a MultiValidator on the given realm. | |
| 160 * | |
| 161 * @param realm | |
| 162 * the realm on which validation takes place. | |
| 163 */ | |
| 164 public this(Realm realm) { | |
| 85 | 165 targetsListener = new TargetsListener(); |
| 166 dependencyListener = new DependencyListener(); | |
| 78 | 167 Assert.isNotNull(realm, "Realm cannot be null"); //$NON-NLS-1$ |
| 168 this.realm = realm; | |
| 169 | |
| 85 | 170 validationStatus = new WritableValue(realm, cast(Object)ValidationStatus.ok(), |
|
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9e0ab372d5d8
Revert from TypeInfo/ClassInfo to java.lang.Class
Frank Benoit <benoit@tionex.de>
parents:
85
diff
changeset
|
171 Class.fromType!(IStatus)); |
| 78 | 172 |
|
88
9e0ab372d5d8
Revert from TypeInfo/ClassInfo to java.lang.Class
Frank Benoit <benoit@tionex.de>
parents:
85
diff
changeset
|
173 targets = new WritableList(realm, new ArrayList(), Class.fromType!(IObservable)); |
| 78 | 174 targets.addListChangeListener(targetsListener); |
| 175 unmodifiableTargets = Observables.unmodifiableObservableList(targets); | |
| 176 | |
| 177 models = Observables.emptyObservableList(realm); | |
| 178 } | |
| 179 | |
| 180 private void checkObservable(IObservable target) { | |
| 85 | 181 Assert.isNotNull(cast(Object)target, "Target observable cannot be null"); //$NON-NLS-1$ |
| 78 | 182 Assert |
| 85 | 183 .isTrue(cast(bool)realm.opEquals(target.getRealm()), |
| 78 | 184 "Target observable must be in the same realm as MultiValidator"); //$NON-NLS-1$ |
| 185 } | |
| 186 | |
| 187 /** | |
| 188 * Returns an {@link IObservableValue} whose value is always the current | |
| 189 * validation status of this MultiValidator. The returned observable is in | |
| 190 * the same realm as this MultiValidator. | |
| 191 * | |
| 192 * @return an {@link IObservableValue} whose value is always the current | |
| 193 * validation status of this MultiValidator. | |
| 194 */ | |
| 195 public IObservableValue getValidationStatus() { | |
| 196 if (unmodifiableValidationStatus is null) { | |
| 197 revalidate(); | |
| 198 unmodifiableValidationStatus = Observables | |
| 199 .unmodifiableObservableValue(validationStatus); | |
| 200 } | |
| 201 return unmodifiableValidationStatus; | |
| 202 } | |
| 203 | |
| 204 private void revalidate() { | |
| 205 final IObservable[] dependencies = ObservableTracker.runAndMonitor( | |
| 206 new class() Runnable { | |
| 207 public void run() { | |
| 208 try { | |
| 209 IStatus status = validate(); | |
| 210 if (status is null) | |
| 211 status = ValidationStatus.ok(); | |
| 85 | 212 validationStatus.setValue(cast(Object)status); |
| 78 | 213 } catch (RuntimeException e) { |
| 214 // Usually an NPE as dependencies are | |
| 215 // init'ed | |
| 85 | 216 validationStatus.setValue(cast(Object)ValidationStatus.error(e |
| 78 | 217 .getMessage(), e)); |
| 218 } | |
| 219 } | |
| 220 }, null, null); | |
| 221 ObservableTracker.runAndIgnore(new class() Runnable { | |
| 222 public void run() { | |
| 223 targets.clear(); | |
| 224 targets.addAll(Arrays.asList(dependencies)); | |
| 225 } | |
| 226 }); | |
| 227 } | |
| 228 | |
| 229 /** | |
| 230 * Return the current validation status. | |
| 231 * <p> | |
| 232 * Note: To ensure that the validation status is kept current, all | |
| 233 * dependencies used to calculate status should be accessed through | |
| 234 * {@link IObservable} instances. Each dependency observable must be in the | |
| 235 * same realm as the MultiValidator. | |
| 236 * | |
| 237 * @return the current validation status. | |
| 238 */ | |
| 239 protected abstract IStatus validate(); | |
| 240 | |
| 241 /** | |
| 242 * Returns a wrapper {@link IObservableValue} which stays in sync with the | |
| 243 * given target observable only when the validation status is valid. | |
| 244 * Statuses of {@link IStatus#OK OK}, {@link IStatus#INFO INFO} or | |
| 245 * {@link IStatus#WARNING WARNING} severity are considered valid. | |
| 246 * <p> | |
| 247 * The wrapper behaves as follows with respect to the validation status: | |
| 248 * <ul> | |
| 249 * <li>While valid, the wrapper stays in sync with its target observable. | |
| 250 * <li>While invalid, the wrapper's value is the target observable's last | |
| 251 * valid value. If the target changes value, a stale event is fired | |
| 252 * signaling that a change is pending. | |
| 253 * <li>When status changes from invalid to valid, the wrapper takes the | |
| 254 * value of the target observable, and synchronization resumes. | |
| 255 * </ul> | |
| 256 * | |
| 257 * @param target | |
| 258 * the target observable being wrapped. Must be in the same realm | |
| 259 * as the MultiValidator. | |
| 260 * @return an IObservableValue which stays in sync with the given target | |
| 261 * observable only with the validation status is valid. | |
| 262 */ | |
| 263 public IObservableValue observeValidatedValue(IObservableValue target) { | |
| 264 checkObservable(target); | |
| 265 return new ValidatedObservableValue(target, getValidationStatus()); | |
| 266 } | |
| 267 | |
| 268 /** | |
| 269 * Returns a wrapper {@link IObservableList} which stays in sync with the | |
| 270 * given target observable only when the validation status is valid. | |
| 271 * Statuses of {@link IStatus#OK OK}, {@link IStatus#INFO INFO} or | |
| 272 * {@link IStatus#WARNING WARNING} severity are considered valid. | |
| 273 * <p> | |
| 274 * The wrapper behaves as follows with respect to the validation status: | |
| 275 * <ul> | |
| 276 * <li>While valid, the wrapper stays in sync with its target observable. | |
| 277 * <li>While invalid, the wrapper's elements are the target observable's | |
| 278 * last valid elements. If the target changes elements, a stale event is | |
| 279 * fired signaling that a change is pending. | |
| 280 * <li>When status changes from invalid to valid, the wrapper takes the | |
| 281 * elements of the target observable, and synchronization resumes. | |
| 282 * </ul> | |
| 283 * | |
| 284 * @param target | |
| 285 * the target observable being wrapped. Must be in the same realm | |
| 286 * as the MultiValidator. | |
| 287 * @return an IObservableValue which stays in sync with the given target | |
| 288 * observable only with the validation status is valid. | |
| 289 */ | |
| 290 public IObservableList observeValidatedList(IObservableList target) { | |
| 291 checkObservable(target); | |
| 292 return new ValidatedObservableList(target, getValidationStatus()); | |
| 293 } | |
| 294 | |
| 295 /** | |
| 296 * Returns a wrapper {@link IObservableSet} which stays in sync with the | |
| 297 * given target observable only when the validation status is valid. | |
| 298 * Statuses of {@link IStatus#OK OK}, {@link IStatus#INFO INFO} or | |
| 299 * {@link IStatus#WARNING WARNING} severity are considered valid. | |
| 300 * <p> | |
| 301 * The wrapper behaves as follows with respect to the validation status: | |
| 302 * <ul> | |
| 303 * <li>While valid, the wrapper stays in sync with its target observable. | |
| 304 * <li>While invalid, the wrapper's elements are the target observable's | |
| 305 * last valid elements. If the target changes elements, a stale event is | |
| 306 * fired signaling that a change is pending. | |
| 307 * <li>When status changes from invalid to valid, the wrapper takes the | |
| 308 * elements of the target observable, and synchronization resumes. | |
| 309 * </ul> | |
| 310 * | |
| 311 * @param target | |
| 312 * the target observable being wrapped. Must be in the same realm | |
| 313 * as the MultiValidator. | |
| 314 * @return an IObservableValue which stays in sync with the given target | |
| 315 * observable only with the validation status is valid. | |
| 316 */ | |
| 317 public IObservableSet observeValidatedSet(IObservableSet target) { | |
| 318 checkObservable(target); | |
| 319 return new ValidatedObservableSet(target, getValidationStatus()); | |
| 320 } | |
| 321 | |
| 322 /** | |
| 323 * Returns a wrapper {@link IObservableMap} which stays in sync with the | |
| 324 * given target observable only when the validation status is valid. | |
| 325 * Statuses of {@link IStatus#OK OK}, {@link IStatus#INFO INFO} or | |
| 326 * {@link IStatus#WARNING WARNING} severity are considered valid. | |
| 327 * <p> | |
| 328 * The wrapper behaves as follows with respect to the validation status: | |
| 329 * <ul> | |
| 330 * <li>While valid, the wrapper stays in sync with its target observable. | |
| 331 * <li>While invalid, the wrapper's entries are the target observable's | |
| 332 * last valid entries. If the target changes entries, a stale event is fired | |
| 333 * signaling that a change is pending. | |
| 334 * <li>When status changes from invalid to valid, the wrapper takes the | |
| 335 * entries of the target observable, and synchronization resumes. | |
| 336 * </ul> | |
| 337 * | |
| 338 * @param target | |
| 339 * the target observable being wrapped. Must be in the same realm | |
| 340 * as the MultiValidator. | |
| 341 * @return an IObservableValue which stays in sync with the given target | |
| 342 * observable only with the validation status is valid. | |
| 343 */ | |
| 344 public IObservableMap observeValidatedMap(IObservableMap target) { | |
| 345 checkObservable(target); | |
| 346 return new ValidatedObservableMap(target, getValidationStatus()); | |
| 347 } | |
| 348 | |
| 349 public IObservableList getTargets() { | |
| 350 return unmodifiableTargets; | |
| 351 } | |
| 352 | |
| 353 public IObservableList getModels() { | |
| 354 return models; | |
| 355 } | |
| 356 | |
| 357 public void dispose() { | |
| 358 targets.clear(); // Remove listeners from dependencies | |
| 359 | |
| 360 unmodifiableValidationStatus.dispose(); | |
| 361 validationStatus.dispose(); | |
| 362 unmodifiableTargets.dispose(); | |
| 363 targets.dispose(); | |
| 364 models.dispose(); | |
| 365 | |
| 366 realm = null; | |
| 367 validationStatus = null; | |
| 368 unmodifiableValidationStatus = null; | |
| 369 targets = null; | |
| 370 unmodifiableTargets = null; | |
| 371 models = null; | |
| 372 | |
| 373 super.dispose(); | |
| 374 } | |
| 375 | |
| 376 } |