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.impl; 018 019 import java.io.File; 020 import java.io.FileInputStream; 021 import java.io.IOException; 022 import java.io.InputStream; 023 import java.lang.annotation.Annotation; 024 import java.net.URL; 025 import java.net.URLConnection; 026 import java.net.URLDecoder; 027 import java.util.Arrays; 028 import java.util.Collections; 029 import java.util.Enumeration; 030 import java.util.HashSet; 031 import java.util.LinkedHashSet; 032 import java.util.Set; 033 import java.util.jar.JarEntry; 034 import java.util.jar.JarInputStream; 035 036 import org.apache.camel.impl.scan.AnnotatedWithAnyPackageScanFilter; 037 import org.apache.camel.impl.scan.AnnotatedWithPackageScanFilter; 038 import org.apache.camel.impl.scan.AssignableToPackageScanFilter; 039 import org.apache.camel.impl.scan.CompositePackageScanFilter; 040 import org.apache.camel.spi.PackageScanClassResolver; 041 import org.apache.camel.spi.PackageScanFilter; 042 import org.apache.camel.util.ObjectHelper; 043 import org.apache.commons.logging.Log; 044 import org.apache.commons.logging.LogFactory; 045 046 /** 047 * Default implement of {@link org.apache.camel.spi.PackageScanClassResolver} 048 */ 049 public class DefaultPackageScanClassResolver implements PackageScanClassResolver { 050 051 protected final transient Log log = LogFactory.getLog(getClass()); 052 private Set<ClassLoader> classLoaders; 053 private Set<PackageScanFilter> scanFilters; 054 055 public void addClassLoader(ClassLoader classLoader) { 056 getClassLoaders().add(classLoader); 057 } 058 059 public void addFilter(PackageScanFilter filter) { 060 if (scanFilters == null) { 061 scanFilters = new LinkedHashSet<PackageScanFilter>(); 062 } 063 scanFilters.add(filter); 064 } 065 066 public Set<ClassLoader> getClassLoaders() { 067 if (classLoaders == null) { 068 classLoaders = new HashSet<ClassLoader>(); 069 ClassLoader ccl = Thread.currentThread().getContextClassLoader(); 070 if (ccl != null) { 071 if (log.isTraceEnabled()) { 072 log.trace("The thread context class loader: " + ccl + " is used to load the class"); 073 } 074 classLoaders.add(ccl); 075 } 076 classLoaders.add(DefaultPackageScanClassResolver.class.getClassLoader()); 077 } 078 return classLoaders; 079 } 080 081 public void setClassLoaders(Set<ClassLoader> classLoaders) { 082 this.classLoaders = classLoaders; 083 } 084 085 @SuppressWarnings("unchecked") 086 public Set<Class> findAnnotated(Class<? extends Annotation> annotation, String... packageNames) { 087 if (packageNames == null) { 088 return Collections.EMPTY_SET; 089 } 090 091 if (log.isDebugEnabled()) { 092 log.debug("Searching for annotations of " + annotation.getName() + " in packages: " + Arrays.asList(packageNames)); 093 } 094 095 PackageScanFilter test = getCompositeFilter(new AnnotatedWithPackageScanFilter(annotation, true)); 096 Set<Class> classes = new LinkedHashSet<Class>(); 097 for (String pkg : packageNames) { 098 find(test, pkg, classes); 099 } 100 101 if (log.isDebugEnabled()) { 102 log.debug("Found: " + classes); 103 } 104 105 return classes; 106 } 107 108 @SuppressWarnings("unchecked") 109 public Set<Class> findAnnotated(Set<Class<? extends Annotation>> annotations, String... packageNames) { 110 if (packageNames == null) { 111 return Collections.EMPTY_SET; 112 } 113 114 if (log.isDebugEnabled()) { 115 log.debug("Searching for annotations of " + annotations + " in packages: " + Arrays.asList(packageNames)); 116 } 117 118 PackageScanFilter test = getCompositeFilter(new AnnotatedWithAnyPackageScanFilter(annotations, true)); 119 Set<Class> classes = new LinkedHashSet<Class>(); 120 for (String pkg : packageNames) { 121 find(test, pkg, classes); 122 } 123 124 if (log.isDebugEnabled()) { 125 log.debug("Found: " + classes); 126 } 127 128 return classes; 129 } 130 131 @SuppressWarnings("unchecked") 132 public Set<Class> findImplementations(Class parent, String... packageNames) { 133 if (packageNames == null) { 134 return Collections.EMPTY_SET; 135 } 136 137 if (log.isDebugEnabled()) { 138 log.debug("Searching for implementations of " + parent.getName() + " in packages: " + Arrays.asList(packageNames)); 139 } 140 141 PackageScanFilter test = getCompositeFilter(new AssignableToPackageScanFilter(parent)); 142 Set<Class> classes = new LinkedHashSet<Class>(); 143 for (String pkg : packageNames) { 144 find(test, pkg, classes); 145 } 146 147 if (log.isDebugEnabled()) { 148 log.debug("Found: " + classes); 149 } 150 151 return classes; 152 } 153 154 @SuppressWarnings("unchecked") 155 public Set<Class> findByFilter(PackageScanFilter filter, String... packageNames) { 156 if (packageNames == null) { 157 return Collections.EMPTY_SET; 158 } 159 160 Set<Class> classes = new LinkedHashSet<Class>(); 161 for (String pkg : packageNames) { 162 find(filter, pkg, classes); 163 } 164 165 if (log.isDebugEnabled()) { 166 log.debug("Found: " + classes); 167 } 168 169 return classes; 170 } 171 172 protected void find(PackageScanFilter test, String packageName, Set<Class> classes) { 173 packageName = packageName.replace('.', '/'); 174 175 Set<ClassLoader> set = getClassLoaders(); 176 177 for (ClassLoader classLoader : set) { 178 find(test, packageName, classLoader, classes); 179 } 180 } 181 182 protected void find(PackageScanFilter test, String packageName, ClassLoader loader, Set<Class> classes) { 183 if (log.isTraceEnabled()) { 184 log.trace("Searching for: " + test + " in package: " + packageName + " using classloader: " 185 + loader.getClass().getName()); 186 } 187 188 Enumeration<URL> urls; 189 try { 190 urls = getResources(loader, packageName); 191 if (!urls.hasMoreElements()) { 192 log.trace("No URLs returned by classloader"); 193 } 194 } catch (IOException ioe) { 195 log.warn("Could not read package: " + packageName, ioe); 196 return; 197 } 198 199 while (urls.hasMoreElements()) { 200 URL url = null; 201 try { 202 url = urls.nextElement(); 203 if (log.isTraceEnabled()) { 204 log.trace("URL from classloader: " + url); 205 } 206 207 String urlPath = url.getFile(); 208 urlPath = URLDecoder.decode(urlPath, "UTF-8"); 209 if (log.isTraceEnabled()) { 210 log.trace("Decoded urlPath: " + urlPath); 211 } 212 213 // If it's a file in a directory, trim the stupid file: spec 214 if (urlPath.startsWith("file:")) { 215 urlPath = urlPath.substring(5); 216 } 217 218 // osgi bundles should be skipped 219 if (url.toString().startsWith("bundle:") || urlPath.startsWith("bundle:")) { 220 log.trace("It's a virtual osgi bundle, skipping"); 221 continue; 222 } 223 224 // Else it's in a JAR, grab the path to the jar 225 if (urlPath.indexOf('!') > 0) { 226 urlPath = urlPath.substring(0, urlPath.indexOf('!')); 227 } 228 229 if (log.isTraceEnabled()) { 230 log.trace("Scanning for classes in [" + urlPath + "] matching criteria: " + test); 231 } 232 233 File file = new File(urlPath); 234 if (file.isDirectory()) { 235 if (log.isDebugEnabled()) { 236 log.debug("Loading from directory: " + file); 237 } 238 loadImplementationsInDirectory(test, packageName, file, classes); 239 } else { 240 InputStream stream; 241 if (urlPath.startsWith("http:")) { 242 // load resources using http such as java webstart 243 log.debug("The current jar is accessed via http"); 244 URL urlStream = new URL(urlPath); 245 URLConnection con = urlStream.openConnection(); 246 // disable cache mainly to avoid jar file locking on Windows 247 con.setUseCaches(false); 248 stream = con.getInputStream(); 249 } else { 250 stream = new FileInputStream(file); 251 } 252 253 if (log.isDebugEnabled()) { 254 log.debug("Loading from jar: " + file); 255 } 256 loadImplementationsInJar(test, packageName, stream, urlPath, classes); 257 } 258 } catch (IOException ioe) { 259 log.warn("Could not read entries in url: " + url, ioe); 260 } 261 } 262 } 263 264 /** 265 * Strategy to get the resources by the given classloader. 266 * <p/> 267 * Notice that in WebSphere platforms there is a {@link WebSpherePacakageScanClassResolver} 268 * to take care of WebSphere's odditiy of resource loading. 269 * 270 * @param loader the classloader 271 * @param packageName the packagename for the package to load 272 * @return URL's for the given package 273 * @throws IOException is thrown by the classloader 274 */ 275 protected Enumeration<URL> getResources(ClassLoader loader, String packageName) throws IOException { 276 if (log.isTraceEnabled()) { 277 log.trace("Getting resource URL for package: " + packageName + " with classloader: " + loader); 278 } 279 return loader.getResources(packageName); 280 } 281 282 private PackageScanFilter getCompositeFilter(PackageScanFilter filter) { 283 if (scanFilters != null) { 284 CompositePackageScanFilter composite = new CompositePackageScanFilter(scanFilters); 285 composite.addFilter(filter); 286 return composite; 287 } 288 return filter; 289 } 290 291 /** 292 * Finds matches in a physical directory on a filesystem. Examines all files 293 * within a directory - if the File object is not a directory, and ends with 294 * <i>.class</i> the file is loaded and tested to see if it is acceptable 295 * according to the Test. Operates recursively to find classes within a 296 * folder structure matching the package structure. 297 * 298 * @param test a Test used to filter the classes that are discovered 299 * @param parent the package name up to this directory in the package 300 * hierarchy. E.g. if /classes is in the classpath and we wish to 301 * examine files in /classes/org/apache then the values of 302 * <i>parent</i> would be <i>org/apache</i> 303 * @param location a File object representing a directory 304 */ 305 private void loadImplementationsInDirectory(PackageScanFilter test, String parent, File location, Set<Class> classes) { 306 File[] files = location.listFiles(); 307 StringBuilder builder = null; 308 309 for (File file : files) { 310 builder = new StringBuilder(100); 311 String name = file.getName(); 312 if (name != null) { 313 name = name.trim(); 314 builder.append(parent).append("/").append(name); 315 String packageOrClass = parent == null ? name : builder.toString(); 316 317 if (file.isDirectory()) { 318 loadImplementationsInDirectory(test, packageOrClass, file, classes); 319 } else if (name.endsWith(".class")) { 320 addIfMatching(test, packageOrClass, classes); 321 } 322 } 323 } 324 } 325 326 /** 327 * Finds matching classes within a jar files that contains a folder 328 * structure matching the package structure. If the File is not a JarFile or 329 * does not exist a warning will be logged, but no error will be raised. 330 * 331 * @param test a Test used to filter the classes that are discovered 332 * @param parent the parent package under which classes must be in order to 333 * be considered 334 * @param stream the inputstream of the jar file to be examined for classes 335 * @param urlPath the url of the jar file to be examined for classes 336 */ 337 private void loadImplementationsInJar(PackageScanFilter test, String parent, InputStream stream, String urlPath, Set<Class> classes) { 338 JarInputStream jarStream = null; 339 try { 340 jarStream = new JarInputStream(stream); 341 342 JarEntry entry; 343 while ((entry = jarStream.getNextJarEntry()) != null) { 344 String name = entry.getName(); 345 if (name != null) { 346 name = name.trim(); 347 if (!entry.isDirectory() && name.startsWith(parent) && name.endsWith(".class")) { 348 addIfMatching(test, name, classes); 349 } 350 } 351 } 352 } catch (IOException ioe) { 353 log.error("Could not search jar file '" + urlPath + "' for classes matching criteria: " + test 354 + " due to an IOException: " + ioe.getMessage(), ioe); 355 } finally { 356 ObjectHelper.close(jarStream, urlPath, log); 357 } 358 } 359 360 /** 361 * Add the class designated by the fully qualified class name provided to 362 * the set of resolved classes if and only if it is approved by the Test 363 * supplied. 364 * 365 * @param test the test used to determine if the class matches 366 * @param fqn the fully qualified name of a class 367 */ 368 @SuppressWarnings("unchecked") 369 protected void addIfMatching(PackageScanFilter test, String fqn, Set<Class> classes) { 370 try { 371 String externalName = fqn.substring(0, fqn.indexOf('.')).replace('/', '.'); 372 Set<ClassLoader> set = getClassLoaders(); 373 boolean found = false; 374 for (ClassLoader classLoader : set) { 375 if (log.isTraceEnabled()) { 376 log.trace("Testing for class " + externalName + " matches criteria [" + test + "] using ClassLoader:" + classLoader); 377 } 378 try { 379 Class type = classLoader.loadClass(externalName); 380 if (log.isTraceEnabled()) { 381 log.trace("Loaded the class: " + type + " in classloader: " + classLoader); 382 } 383 if (test.matches(type)) { 384 if (log.isTraceEnabled()) { 385 log.trace("Found class: " + type + " which matches the filter in classloader: " + classLoader); 386 } 387 classes.add(type); 388 } 389 found = true; 390 break; 391 } catch (ClassNotFoundException e) { 392 log.debug("Could not find class '" + fqn + "' in classloader: " + classLoader 393 + ". Reason: " + e, e); 394 } catch (NoClassDefFoundError e) { 395 log.debug("Could not find the class defintion '" + fqn + "' in classloader: " + classLoader 396 + ". Reason: " + e, e); 397 } 398 } 399 if (!found) { 400 log.warn("Could not find class '" + fqn + "' in any classloaders: " + set); 401 } 402 } catch (Exception e) { 403 log.warn("Could not examine class '" + fqn + "' due to a " + e.getClass().getName() 404 + " with message: " + e.getMessage(), e); 405 } 406 } 407 408 }