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1
7
8 package org.jdesktop.swing.binding;
9
10 import org.jdesktop.swing.data.ConversionException;
11 import org.jdesktop.swing.data.Converter;
12 import org.jdesktop.swing.data.DataModel;
13 import org.jdesktop.swing.data.MetaData;
14 import org.jdesktop.swing.data.Validator;
15 import org.jdesktop.swing.data.ValueChangeEvent;
16 import org.jdesktop.swing.data.ValueChangeListener;
17 import java.beans.PropertyChangeListener  ;
18 import java.beans.PropertyChangeSupport ;
19
20 import java.util.ArrayList ;
21
22 import javax.swing.InputVerifier ;
23 import javax.swing.JComponent ;
24
25
34
35 public abstract class AbstractBinding implements Binding {
36
37 protected DataModel dataModel;
38 protected MetaData metaData;
39 private String fieldName;
40 protected Object cachedValue;
41 protected ArrayList errorList;
42 protected boolean modified = false;
43 protected int validState = UNVALIDATED;
44 protected boolean pulling = false;
45 protected boolean pushing = false;
46
47 private PropertyChangeSupport pcs;
48 private int validationPolicy;
49 private static final PropertyChangeListener []
50 EMPTY_PROPERTY_CHANGE_LISTENER_ARRAY = new PropertyChangeListener [0];
51
52
61 protected AbstractBinding(JComponent component,
62 DataModel dataModel, String fieldName,
63 int validationPolicy) {
64 checkNull(component, "component must not be null");
65 checkNull(dataModel, "model must not be null");
66 checkNull(fieldName, "fieldName must not be null");
67 installDataModel(dataModel, fieldName);
68 setComponent(component);
69 setValidationPolicy(validationPolicy);
70 }
71
72
74 public DataModel getDataModel() {
75 return dataModel;
76 }
77
78 public String getFieldName() {
79 return fieldName;
80 }
81
82
86 public void setValidationPolicy(int policy) {
87 int oldValidationPolicy = this.validationPolicy;
88 this.validationPolicy = policy;
89 installInputVerifier();
90 if (policy != oldValidationPolicy) {
91 firePropertyChange("validationPolicy",
92 new Integer (oldValidationPolicy),
93 new Integer (policy));
94 }
95 }
96
97
98 public int getValidationPolicy() {
99 return validationPolicy;
100 }
101
102 public boolean pull() {
103 pulling = true;
104 cachedValue = dataModel.getValue(metaData.getName());
106 setComponentValue(cachedValue);
107 setModified(false);
109 setValidState(UNVALIDATED);
110 isValid();
112 pulling = false;
113 return true;
114 }
115
116 public boolean push() {
117 if (isValid()) {
118 pushing = true;
119 dataModel.setValue(metaData.getName(), cachedValue);
120 setModified(false);
121 pushing = false;
122 return true;
123 }
124 return false;
125 }
126
127 public boolean isModified() {
128 return modified;
129 }
130
131 public boolean isValid() {
132 if (validState != UNVALIDATED) {
133 return validState == VALID;
134 }
135 clearValidationErrors();
137 Object componentValue = getComponentValue();
138
139 boolean ok = checkRequired(componentValue);
141
142 Object convertedValue = null;
145 if (ok) {
146 try {
147 convertedValue = convertToModelType(componentValue);
148 } catch (Exception e) {
149 ok = false;
150
151 addError("value must be type " + metaData.getElementClass().getName());
152 }
153 }
154
155 if (ok) {
157 ok = executeValidators(convertedValue);
158 }
159
160 if (ok) {
161 cachedValue = convertedValue;
162 }
163 setValidState(ok? VALID : INVALID);
164
165 return validState == VALID;
166
167 }
168
169 public int getValidState() {
170 return validState;
171 }
172
173
174 public String [] getValidationErrors() {
175 if (errorList != null) {
176 return (String [])errorList.toArray(new String [1]);
177 }
178 return new String [0];
179 }
180
181 public void clearValidationErrors() {
182 if (errorList != null) {
183 errorList.clear();
184 }
185 }
186
187
188
193 public void addPropertyChangeListener(PropertyChangeListener pcl) {
194 if (pcs == null) {
195 pcs = new PropertyChangeSupport (this);
196
197 }
198 pcs.addPropertyChangeListener(pcl);
199 }
200
201
206 public void removePropertyChangeListener(PropertyChangeListener pcl) {
207 pcs.removePropertyChangeListener(pcl);
208 }
209
210
215 public PropertyChangeListener [] getPropertyChangeListeners() {
216 if (pcs == null) return EMPTY_PROPERTY_CHANGE_LISTENER_ARRAY;
217 return pcs.getPropertyChangeListeners();
218 }
219
220 protected void firePropertyChange(String propertyName,
221 Object oldValue, Object newValue) {
222 if (pcs == null) return;
223 pcs.firePropertyChange(propertyName, oldValue, newValue);
224 }
225
226
227
229
233 protected abstract void setComponent(JComponent component);
234 protected abstract Object getComponentValue();
235 protected abstract void setComponentValue(Object value);
236
237
239 protected boolean checkRequired(Object componentValue) {
240 if (metaData.isRequired() && isEmpty(componentValue)) {
242 addError("requires a value");
243 return false;
244 }
245 return true;
246 }
249
250 protected boolean isEmpty(Object componentValue) {
251 return (componentValue == null ||
252 (componentValue instanceof String && ((String )componentValue).equals("")));
253 }
254
255 protected Object convertToModelType(Object componentValue) throws ConversionException {
256 Object convertedValue = null;
257 if (isEmpty(componentValue)) {
260 return convertedValue;
261 }
262 Class elementClass = metaData.getElementClass();
263 if (componentValue instanceof String ) {
264 String stringValue = (String ) componentValue;
265 Converter converter = metaData.getConverter();
266 if (converter != null) {
267 convertedValue = converter.decode(stringValue,
268 metaData.getDecodeFormat());
269 } else if (metaData.getElementClass() == String .class) {
270 convertedValue = componentValue;
271 }
272 }
273 else {
274 if (!elementClass.isAssignableFrom(componentValue.getClass())) {
275 throw new ConversionException("cannot assign component value");
276 } else {
277 convertedValue = componentValue;
278 }
279 }
280 return convertedValue;
281 }
282
283 protected String convertFromModelType(Object modelValue) {
284 if (modelValue != null) {
285 try {
286 Converter converter = metaData.getConverter();
287 return converter.encode(modelValue, metaData.getEncodeFormat());
288 }
289 catch (Exception e) {
290
291 return modelValue.toString();
292 }
293 }
294 return "";
295 }
296
297 protected boolean executeValidators(Object value) {
298 Validator validators[] = metaData.getValidators();
299 boolean isValid = true;
300 for (int i = 0; i < validators.length; i++) {
301 String error[] = new String [1];
302 boolean passed = validators[i].validate(value, null, error);
303 if (!passed) {
304 String errorMessage = error[0];
305 if (errorMessage != null) {
306 addError(errorMessage);
307 }
308 isValid = false;
309 }
310 }
311 return isValid;
312 }
313
314 protected void addError(String error) {
315 if (errorList == null) {
316 errorList = new ArrayList ();
317 }
318 errorList.add(error);
319 }
320
321
322 protected void setModified(boolean modified) {
323 boolean oldModified = this.modified;
328 this.modified = modified;
329 if (modified) {
330 cachedValue = null;
331 setValidState(UNVALIDATED);
332 }
333 if (oldModified != modified) {
334 firePropertyChange("modified",
335 Boolean.valueOf(oldModified),
336 Boolean.valueOf(modified));
337 }
338 }
339
340 protected void setValidState(int validState) {
341 int oldValidState = this.validState;
342 this.validState = validState;
343 if (oldValidState != validState &&
344 validState == UNVALIDATED) {
345 clearValidationErrors();
346 }
347 if (validState != oldValidState) {
348 firePropertyChange("validState",
349 new Integer (oldValidState),
350 new Integer (validState));
351 }
352 }
353
354
355
358 protected void installInputVerifier() {
359 getComponent().setInputVerifier(new InputVerifier () {
360 public boolean verify(JComponent input) {
361 if (validationPolicy != AUTO_VALIDATE_NONE) {
362 boolean isValid = isValid();
363 if (!isValid && validationPolicy == AUTO_VALIDATE_STRICT) {
364 return false;
365 }
366 return true;
367 }
368 return true;
369 }
370 });
371 }
372
373
375 protected void checkNull(Object component, String message) {
376 if (component == null) throw new NullPointerException (message);
377 }
378
379 protected void installDataModel(DataModel dataModel, String fieldName) {
380 this.dataModel = dataModel;
381 this.fieldName = fieldName;
382 metaData = dataModel.getMetaData(fieldName);
383 installDataModelListener();
384 installMetaDataListener();
385 }
386
387 protected void installDataModelListener() {
388 dataModel.addValueChangeListener(new ValueChangeListener() {
389 public void valueChanged(ValueChangeEvent e) {
390 if (e.getFieldName().equals(fieldName) &&
391 !pushing) {
392 pull();
393 }
394 }
395 });
396 }
397
398
399
404 protected void installMetaDataListener() {
405 }
416
417 }
418 |
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