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