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1
61
62 package org.apache.commons.dbutils;
63
64 import java.beans.BeanInfo  ;
65 import java.beans.IntrospectionException ;
66 import java.beans.Introspector ;
67 import java.beans.PropertyDescriptor ;
68 import java.lang.reflect.InvocationTargetException ;
69 import java.lang.reflect.Method ;
70 import java.sql.ResultSet ;
71 import java.sql.ResultSetMetaData ;
72 import java.sql.SQLException ;
73 import java.util.ArrayList ;
74 import java.util.HashMap ;
75 import java.util.Iterator ;
76 import java.util.List ;
77 import java.util.Map ;
78
79
90 public class BasicRowProcessor implements RowProcessor {
91
92
97 private static final Map primitiveDefaults = new HashMap ();
98
99 static {
100 primitiveDefaults.put(Integer.TYPE, new Integer (0));
101 primitiveDefaults.put(Short.TYPE, new Short ((short) 0));
102 primitiveDefaults.put(Byte.TYPE, new Byte ((byte) 0));
103 primitiveDefaults.put(Float.TYPE, new Float (0));
104 primitiveDefaults.put(Double.TYPE, new Double (0));
105 primitiveDefaults.put(Long.TYPE, new Long (0));
106 primitiveDefaults.put(Boolean.TYPE, Boolean.FALSE);
107 primitiveDefaults.put(Character.TYPE, new Character ('\u0000'));
108 }
109
110
114 private static final int PROPERTY_NOT_FOUND = -1;
115
116
119 private static final BasicRowProcessor instance = new BasicRowProcessor();
120
121
126 public static BasicRowProcessor instance() {
127 return instance;
128 }
129
130
133 protected BasicRowProcessor() {
134 super();
135 }
136
137
145 public Object [] toArray(ResultSet rs) throws SQLException {
146 ResultSetMetaData meta = rs.getMetaData();
147 int cols = meta.getColumnCount();
148 Object [] result = new Object [cols];
149
150 for (int i = 0; i < cols; i++) {
151 result[i] = rs.getObject(i + 1);
152 }
153
154 return result;
155 }
156
157
185 public Object toBean(ResultSet rs, Class type) throws SQLException {
186
187 PropertyDescriptor [] props = this.propertyDescriptors(type);
188
189 ResultSetMetaData rsmd = rs.getMetaData();
190
191 int[] columnToProperty = this.mapColumnsToProperties(rsmd, props);
192
193 int cols = rsmd.getColumnCount();
194
195 return this.createBean(rs, type, props, columnToProperty, cols);
196 }
197
198
226 public List toBeanList(ResultSet rs, Class type) throws SQLException {
227 List results = new ArrayList ();
228
229 if (!rs.next()) {
230 return results;
231 }
232
233 PropertyDescriptor [] props = this.propertyDescriptors(type);
234 ResultSetMetaData rsmd = rs.getMetaData();
235 int[] columnToProperty = this.mapColumnsToProperties(rsmd, props);
236 int cols = rsmd.getColumnCount();
237
238 do {
239 results.add(this.createBean(rs, type, props, columnToProperty, cols));
240
241 } while (rs.next());
242
243 return results;
244 }
245
246
257 private Object createBean(
258 ResultSet rs,
259 Class type,
260 PropertyDescriptor [] props,
261 int[] columnToProperty,
262 int cols)
263 throws SQLException {
264
265 Object bean = this.newInstance(type);
266
267 for (int i = 1; i <= cols; i++) {
268
269 if (columnToProperty[i] == PROPERTY_NOT_FOUND) {
270 continue;
271 }
272
273 Object value = rs.getObject(i);
274
275 PropertyDescriptor prop = props[columnToProperty[i]];
276 Class propType = prop.getPropertyType();
277
278 if (propType != null && value == null && propType.isPrimitive()) {
279 value = primitiveDefaults.get(propType);
280 }
281
282 this.callSetter(bean, prop, value);
283 }
284
285 return bean;
286 }
287
288
301 private int[] mapColumnsToProperties(
302 ResultSetMetaData rsmd,
303 PropertyDescriptor [] props)
304 throws SQLException {
305
306 int cols = rsmd.getColumnCount();
307 int columnToProperty[] = new int[cols + 1];
308
309 for (int col = 1; col <= cols; col++) {
310 String columnName = rsmd.getColumnName(col);
311 for (int i = 0; i < props.length; i++) {
312
313 if (columnName.equalsIgnoreCase(props[i].getName())) {
314 columnToProperty[col] = i;
315 break;
316
317 } else {
318 columnToProperty[col] = PROPERTY_NOT_FOUND;
319 }
320 }
321 }
322
323 return columnToProperty;
324 }
325
326
333 public Map toMap(ResultSet rs) throws SQLException {
334 Map result = new CaseInsensitiveHashMap();
335 ResultSetMetaData rsmd = rs.getMetaData();
336 int cols = rsmd.getColumnCount();
337
338 for (int i = 1; i <= cols; i++) {
339 result.put(rsmd.getColumnName(i), rs.getObject(i));
340 }
341
342 return result;
343 }
344
345
353 private void callSetter(
354 Object target,
355 PropertyDescriptor prop,
356 Object value)
357 throws SQLException {
358
359 Method setter = prop.getWriteMethod();
360
361 if (setter == null) {
362 return;
363 }
364
365 Class [] params = setter.getParameterTypes();
366 try {
367 if (this.isCompatibleType(value, params[0])) {
369 setter.invoke(target, new Object [] { value });
370 }
371
372 } catch (IllegalArgumentException e) {
373 throw new SQLException (
374 "Cannot set " + prop.getName() + ": " + e.getMessage());
375
376 } catch (IllegalAccessException e) {
377 throw new SQLException (
378 "Cannot set " + prop.getName() + ": " + e.getMessage());
379
380 } catch (InvocationTargetException e) {
381 throw new SQLException (
382 "Cannot set " + prop.getName() + ": " + e.getMessage());
383 }
384 }
385
386
397 private boolean isCompatibleType(Object value, Class type) {
398 if (value == null || type.isInstance(value)) {
400 return true;
401
402 } else if (
403 type.equals(Integer.TYPE) && Integer .class.isInstance(value)) {
404 return true;
405
406 } else if (type.equals(Long.TYPE) && Long .class.isInstance(value)) {
407 return true;
408
409 } else if (
410 type.equals(Double.TYPE) && Double .class.isInstance(value)) {
411 return true;
412
413 } else if (type.equals(Float.TYPE) && Float .class.isInstance(value)) {
414 return true;
415
416 } else if (type.equals(Short.TYPE) && Short .class.isInstance(value)) {
417 return true;
418
419 } else if (type.equals(Byte.TYPE) && Byte .class.isInstance(value)) {
420 return true;
421
422 } else if (
423 type.equals(Character.TYPE) && Character .class.isInstance(value)) {
424 return true;
425
426 } else if (
427 type.equals(Boolean.TYPE) && Boolean .class.isInstance(value)) {
428 return true;
429
430 } else {
431 return false;
432 }
433
434 }
435
436
443 private Object newInstance(Class c) throws SQLException {
444 try {
445 return c.newInstance();
446
447 } catch (InstantiationException e) {
448 throw new SQLException (
449 "Cannot create " + c.getName() + ": " + e.getMessage());
450
451 } catch (IllegalAccessException e) {
452 throw new SQLException (
453 "Cannot create " + c.getName() + ": " + e.getMessage());
454 }
455 }
456
457
464 private PropertyDescriptor [] propertyDescriptors(Class c)
465 throws SQLException {
466 BeanInfo beanInfo = null;
468 try {
469 beanInfo = Introspector.getBeanInfo(c);
470
471 } catch (IntrospectionException e) {
472 throw new SQLException (
473 "Bean introspection failed: " + e.getMessage());
474 }
475
476 return beanInfo.getPropertyDescriptors();
477 }
478
479
484 private static class CaseInsensitiveHashMap extends HashMap {
485
486
489 public boolean containsKey(Object key) {
490 return super.containsKey(key.toString().toLowerCase());
491 }
492
493
496 public Object get(Object key) {
497 return super.get(key.toString().toLowerCase());
498 }
499
500
503 public Object put(Object key, Object value) {
504 return super.put(key.toString().toLowerCase(), value);
505 }
506
507
510 public void putAll(Map m) {
511 Iterator iter = m.keySet().iterator();
512 while (iter.hasNext()) {
513 Object key = iter.next();
514 Object value = m.get(key);
515 this.put(key, value);
516 }
517 }
518
519
522 public Object remove(Object key) {
523 return super.remove(key.toString().toLowerCase());
524 }
525 }
526
527 }
528 |
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