001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 package org.apache.camel.util; 018 019 import java.beans.PropertyEditor; 020 import java.beans.PropertyEditorManager; 021 import java.lang.reflect.Field; 022 import java.lang.reflect.InvocationTargetException; 023 import java.lang.reflect.Method; 024 import java.lang.reflect.Modifier; 025 import java.net.URI; 026 import java.net.URISyntaxException; 027 import java.util.Arrays; 028 import java.util.HashMap; 029 import java.util.Iterator; 030 import java.util.LinkedHashMap; 031 import java.util.LinkedHashSet; 032 import java.util.Map; 033 import java.util.Set; 034 035 import org.apache.camel.NoTypeConversionAvailableException; 036 import org.apache.camel.TypeConverter; 037 import org.apache.commons.logging.Log; 038 import org.apache.commons.logging.LogFactory; 039 040 /** 041 * Helper for introspections of beans. 042 */ 043 public final class IntrospectionSupport { 044 045 private static final transient Log LOG = LogFactory.getLog(IntrospectionSupport.class); 046 047 /** 048 * Utility classes should not have a public constructor. 049 */ 050 private IntrospectionSupport() { 051 } 052 053 /** 054 * Copies the properties from the source to the target 055 * @param source source object 056 * @param target target object 057 * @param optionPrefix optional option preifx (can be null) 058 * @return true if properties is copied, false if something went wrong 059 */ 060 public static boolean copyProperties(Object source, Object target, String optionPrefix) { 061 Map properties = new LinkedHashMap(); 062 if (!getProperties(source, properties, optionPrefix)) { 063 return false; 064 } 065 try { 066 return setProperties(target, properties, optionPrefix); 067 } catch (Exception e) { 068 LOG.debug("Can not copy properties to target: " + target, e); 069 return false; 070 } 071 } 072 073 @SuppressWarnings("unchecked") 074 public static boolean getProperties(Object target, Map properties, String optionPrefix) { 075 ObjectHelper.notNull(target, "target"); 076 ObjectHelper.notNull(properties, "properties"); 077 boolean rc = false; 078 if (optionPrefix == null) { 079 optionPrefix = ""; 080 } 081 082 Class clazz = target.getClass(); 083 Method[] methods = clazz.getMethods(); 084 for (Method method : methods) { 085 String name = method.getName(); 086 Class type = method.getReturnType(); 087 Class params[] = method.getParameterTypes(); 088 if (name.startsWith("get") && params.length == 0 && type != null && isSettableType(type)) { 089 try { 090 Object value = method.invoke(target); 091 if (value == null) { 092 continue; 093 } 094 095 String strValue = convertToString(value, type); 096 if (strValue == null) { 097 continue; 098 } 099 100 name = name.substring(3, 4).toLowerCase() + name.substring(4); 101 properties.put(optionPrefix + name, strValue); 102 rc = true; 103 } catch (Exception ignore) { 104 // ignore 105 } 106 } 107 } 108 109 return rc; 110 } 111 112 public static boolean hasProperties(Map properties, String optionPrefix) { 113 ObjectHelper.notNull(properties, "properties"); 114 115 if (ObjectHelper.isNotEmpty(optionPrefix)) { 116 for (Object o : properties.keySet()) { 117 String name = (String) o; 118 if (name.startsWith(optionPrefix)) { 119 return true; 120 } 121 } 122 // no parameters with this prefix 123 return false; 124 } else { 125 return !properties.isEmpty(); 126 } 127 } 128 129 public static Object getProperty(Object target, String property) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { 130 ObjectHelper.notNull(target, "target"); 131 ObjectHelper.notNull(property, "property"); 132 133 property = property.substring(0, 1).toUpperCase() + property.substring(1); 134 135 Class clazz = target.getClass(); 136 Method method = getPropertyGetter(clazz, property); 137 return method.invoke(target); 138 } 139 140 public static Method getPropertyGetter(Class type, String propertyName) throws NoSuchMethodException { 141 return type.getMethod("get" + ObjectHelper.capitalize(propertyName)); 142 } 143 144 public static boolean setProperties(Object target, Map properties, String optionPrefix) throws Exception { 145 ObjectHelper.notNull(target, "target"); 146 ObjectHelper.notNull(properties, "properties"); 147 boolean rc = false; 148 149 for (Iterator iter = properties.keySet().iterator(); iter.hasNext();) { 150 String name = (String)iter.next(); 151 if (name.startsWith(optionPrefix)) { 152 Object value = properties.get(name); 153 name = name.substring(optionPrefix.length()); 154 if (setProperty(target, name, value)) { 155 iter.remove(); 156 rc = true; 157 } 158 } 159 } 160 return rc; 161 } 162 163 @SuppressWarnings("unchecked") 164 public static Map extractProperties(Map properties, String optionPrefix) { 165 ObjectHelper.notNull(properties, "properties"); 166 167 HashMap rc = new LinkedHashMap(properties.size()); 168 169 for (Iterator iter = properties.keySet().iterator(); iter.hasNext();) { 170 String name = (String)iter.next(); 171 if (name.startsWith(optionPrefix)) { 172 Object value = properties.get(name); 173 name = name.substring(optionPrefix.length()); 174 rc.put(name, value); 175 iter.remove(); 176 } 177 } 178 179 return rc; 180 } 181 182 public static boolean setProperties(TypeConverter typeConverter, Object target, Map properties) throws Exception { 183 ObjectHelper.notNull(target, "target"); 184 ObjectHelper.notNull(properties, "properties"); 185 boolean rc = false; 186 187 for (Iterator iter = properties.entrySet().iterator(); iter.hasNext();) { 188 Map.Entry entry = (Map.Entry)iter.next(); 189 if (setProperty(typeConverter, target, (String)entry.getKey(), entry.getValue())) { 190 iter.remove(); 191 rc = true; 192 } 193 } 194 195 return rc; 196 } 197 198 public static boolean setProperties(Object target, Map props) throws Exception { 199 return setProperties(null, target, props); 200 } 201 202 public static boolean setProperty(TypeConverter typeConverter, Object target, String name, Object value) throws Exception { 203 try { 204 Class clazz = target.getClass(); 205 // find candidates of setter methods as there can be overloaded setters 206 Set<Method> setters = findSetterMethods(typeConverter, clazz, name, value); 207 if (setters.isEmpty()) { 208 return false; 209 } 210 211 // loop and execute the best setter method 212 Exception typeConvertionFailed = null; 213 for (Method setter : setters) { 214 // If the type is null or it matches the needed type, just use the value directly 215 if (value == null || setter.getParameterTypes()[0].isAssignableFrom(value.getClass())) { 216 setter.invoke(target, value); 217 return true; 218 } else { 219 // We need to convert it 220 try { 221 // ignore exceptions as there could be another setter method where we could type convert successfully 222 Object convertedValue = convert(typeConverter, setter.getParameterTypes()[0], value); 223 setter.invoke(target, convertedValue); 224 return true; 225 } catch (NoTypeConversionAvailableException e) { 226 typeConvertionFailed = e; 227 } catch (IllegalArgumentException e) { 228 typeConvertionFailed = e; 229 } 230 if (LOG.isTraceEnabled()) { 231 LOG.trace("Setter \"" + setter + "\" with parameter type \"" 232 + setter.getParameterTypes()[0] + "\" could not be used for type conversions of " + value); 233 } 234 } 235 } 236 // we did not find a setter method to use, and if we did try to use a type converter then throw 237 // this kind of exception as the caused by will hint this error 238 if (typeConvertionFailed != null) { 239 throw new IllegalArgumentException("Could not find a suitable setter for property: " + name 240 + " as there isn't a setter method with same type: " + value.getClass().getCanonicalName() 241 + " nor type conversion possible: " + typeConvertionFailed.getMessage()); 242 } else { 243 return false; 244 } 245 } catch (InvocationTargetException e) { 246 // lets unwrap the exception 247 Throwable throwable = e.getCause(); 248 if (throwable instanceof Exception) { 249 Exception exception = (Exception)throwable; 250 throw exception; 251 } else { 252 Error error = (Error)throwable; 253 throw error; 254 } 255 } 256 } 257 258 public static boolean setProperty(Object target, String name, Object value) throws Exception { 259 return setProperty(null, target, name, value); 260 } 261 262 @SuppressWarnings("unchecked") 263 private static Object convert(TypeConverter typeConverter, Class type, Object value) throws URISyntaxException { 264 if (typeConverter != null) { 265 return typeConverter.convertTo(type, value); 266 } 267 PropertyEditor editor = PropertyEditorManager.findEditor(type); 268 if (editor != null) { 269 editor.setAsText(value.toString()); 270 return editor.getValue(); 271 } 272 if (type == URI.class) { 273 return new URI(value.toString()); 274 } 275 return null; 276 } 277 278 private static String convertToString(Object value, Class type) throws URISyntaxException { 279 PropertyEditor editor = PropertyEditorManager.findEditor(type); 280 if (editor != null) { 281 editor.setValue(value); 282 return editor.getAsText(); 283 } 284 if (type == URI.class) { 285 return value.toString(); 286 } 287 return null; 288 } 289 290 private static Set<Method> findSetterMethods(TypeConverter typeConverter, Class clazz, String name, Object value) { 291 Set<Method> candidates = new LinkedHashSet<Method>(); 292 293 // Build the method name. 294 name = "set" + ObjectHelper.capitalize(name); 295 while (clazz != Object.class) { 296 // Since Object.class.isInstance all the objects, 297 // here we just make sure it will be add to the bottom of the set. 298 Method objectSetMethod = null; 299 Method[] methods = clazz.getMethods(); 300 for (Method method : methods) { 301 Class params[] = method.getParameterTypes(); 302 if (method.getName().equals(name) && params.length == 1) { 303 Class paramType = params[0]; 304 if (paramType.equals(Object.class)) { 305 objectSetMethod = method; 306 } else if (typeConverter != null || isSettableType(paramType) || paramType.isInstance(value)) { 307 candidates.add(method); 308 } 309 } 310 } 311 if (objectSetMethod != null) { 312 candidates.add(objectSetMethod); 313 } 314 clazz = clazz.getSuperclass(); 315 } 316 317 if (candidates.isEmpty()) { 318 return candidates; 319 } else if (candidates.size() == 1) { 320 // only one 321 return candidates; 322 } else { 323 // find the best match if possible 324 if (LOG.isTraceEnabled()) { 325 LOG.trace("Found " + candidates.size() + " suitable setter methods for setting " + name); 326 } 327 // prefer to use the one with the same instance if any exists 328 for (Method method : candidates) { 329 if (method.getParameterTypes()[0].isInstance(value)) { 330 if (LOG.isTraceEnabled()) { 331 LOG.trace("Method " + method + " is the best candidate as it has parameter with same instance type"); 332 } 333 // retain only this method in the answer 334 candidates.clear(); 335 candidates.add(method); 336 return candidates; 337 } 338 } 339 // fallback to return what we have found as candidates so far 340 return candidates; 341 } 342 } 343 344 private static boolean isSettableType(Class clazz) { 345 if (PropertyEditorManager.findEditor(clazz) != null) { 346 return true; 347 } 348 if (clazz == URI.class) { 349 return true; 350 } 351 if (clazz == Boolean.class) { 352 return true; 353 } 354 return false; 355 } 356 357 public static String toString(Object target) { 358 return toString(target, Object.class); 359 } 360 361 public static String toString(Object target, Class stopClass) { 362 LinkedHashMap map = new LinkedHashMap(); 363 addFields(target, target.getClass(), stopClass, map); 364 StringBuffer buffer = new StringBuffer(simpleName(target.getClass())); 365 buffer.append(" {"); 366 Set entrySet = map.entrySet(); 367 boolean first = true; 368 for (Iterator iter = entrySet.iterator(); iter.hasNext();) { 369 Map.Entry entry = (Map.Entry)iter.next(); 370 if (first) { 371 first = false; 372 } else { 373 buffer.append(", "); 374 } 375 buffer.append(entry.getKey()); 376 buffer.append(" = "); 377 appendToString(buffer, entry.getValue()); 378 } 379 buffer.append("}"); 380 return buffer.toString(); 381 } 382 383 protected static void appendToString(StringBuffer buffer, Object value) { 384 buffer.append(value); 385 } 386 387 public static String simpleName(Class clazz) { 388 String name = clazz.getName(); 389 int p = name.lastIndexOf("."); 390 if (p >= 0) { 391 name = name.substring(p + 1); 392 } 393 return name; 394 } 395 396 @SuppressWarnings("unchecked") 397 private static void addFields(Object target, Class startClass, Class stopClass, LinkedHashMap map) { 398 if (startClass != stopClass) { 399 addFields(target, startClass.getSuperclass(), stopClass, map); 400 } 401 402 Field[] fields = startClass.getDeclaredFields(); 403 for (Field field : fields) { 404 if (Modifier.isStatic(field.getModifiers()) || Modifier.isTransient(field.getModifiers()) 405 || Modifier.isPrivate(field.getModifiers())) { 406 continue; 407 } 408 409 try { 410 field.setAccessible(true); 411 Object o = field.get(target); 412 if (o != null && o.getClass().isArray()) { 413 try { 414 o = Arrays.asList((Object[])o); 415 } catch (Throwable e) { 416 // ignore 417 } 418 } 419 map.put(field.getName(), o); 420 } catch (Throwable e) { 421 throw ObjectHelper.wrapRuntimeCamelException(e); 422 } 423 } 424 } 425 426 }