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