MultiDex.java revision 88117c37e2c3f8601f295b74a3e804877afb78ee
1/* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package android.support.multidex; 18 19import dalvik.system.DexFile; 20 21import android.content.Context; 22import android.content.pm.ApplicationInfo; 23import android.content.pm.PackageManager; 24import android.os.Build; 25import android.util.Log; 26 27import java.io.File; 28import java.io.IOException; 29import java.lang.reflect.Array; 30import java.lang.reflect.Field; 31import java.lang.reflect.InvocationTargetException; 32import java.lang.reflect.Method; 33import java.util.ArrayList; 34import java.util.Arrays; 35import java.util.HashSet; 36import java.util.List; 37import java.util.ListIterator; 38import java.util.Set; 39import java.util.zip.ZipFile; 40 41/** 42 * Monkey patches {@link Context#getClassLoader() the application context class 43 * loader} in order to load classes from more than one dex file. The primary 44 * {@code classes.dex} file necessary for calling this class methods. secondary 45 * dex files named classes2.dex, classes".dex... found in the application apk 46 * will be added to the classloader after first call to 47 * {@link #install(Context)}. 48 * 49 * <p/> 50 * <strong>IMPORTANT:</strong>This library provides compatibility for platforms 51 * with API level 4 through 19. This library does nothing on newer versions of 52 * the platform which provide built-in support for secondary dex files. 53 */ 54public final class MultiDex { 55 56 static final String TAG = "MultiDex"; 57 58 private static final String SECONDARY_FOLDER_NAME = "secondary-dexes"; 59 60 private static final int SUPPORTED_MULTIDEX_SDK_VERSION = 20; 61 62 private static final int MIN_SDK_VERSION = 4; 63 64 private static final Set<String> installedApk = new HashSet<String>(); 65 66 private MultiDex() {} 67 68 /** 69 * Patches the application context class loader by appending extra dex files 70 * loaded from the application apk. Call this method first thing in your 71 * {@code Application#OnCreate}, {@code Instrumentation#OnCreate}, 72 * {@code BackupAgent#OnCreate}, {@code Service#OnCreate}, 73 * {@code BroadcastReceiver#onReceive}, {@code Activity#OnCreate} and 74 * {@code ContentProvider#OnCreate} . 75 * 76 * @param context application context. 77 * @throws RuntimeException if an error occurred preventing the classloader 78 * extension. 79 */ 80 public static void install(Context context) { 81 82 if (Build.VERSION.SDK_INT < MIN_SDK_VERSION) { 83 throw new RuntimeException("Multi dex installation failed. SDK " + Build.VERSION.SDK_INT 84 + " is unsupported. Min SDK version is " + MIN_SDK_VERSION + "."); 85 } 86 87 88 try { 89 PackageManager pm; 90 String packageName; 91 try { 92 pm = context.getPackageManager(); 93 packageName = context.getPackageName(); 94 } catch (RuntimeException e) { 95 /* Ignore those exceptions so that we don't break tests relying on Context like 96 * a android.test.mock.MockContext or a android.content.ContextWrapper with a null 97 * base Context. 98 */ 99 Log.w(TAG, "Failure while trying to obtain ApplicationInfo from Context. " + 100 "Must be running in test mode. Skip patching.", e); 101 return; 102 } 103 if (pm == null || packageName == null) { 104 // This is most likely a mock context, so just return without patching. 105 return; 106 } 107 ApplicationInfo applicationInfo = 108 pm.getApplicationInfo(packageName, PackageManager.GET_META_DATA); 109 if (applicationInfo == null) { 110 // This is from a mock context, so just return without patching. 111 return; 112 } 113 114 synchronized (installedApk) { 115 String apkPath = applicationInfo.sourceDir; 116 if (installedApk.contains(apkPath)) { 117 return; 118 } 119 installedApk.add(apkPath); 120 121 if (Build.VERSION.SDK_INT >= SUPPORTED_MULTIDEX_SDK_VERSION) { 122 // STOPSHIP: Any app that uses this class needs approval before being released 123 // as well as figuring out what the right behavior should be here. 124 throw new RuntimeException("Platform support of multidex for SDK " + 125 Build.VERSION.SDK_INT + " has not been confirmed yet."); 126 } 127 128 /* The patched class loader is expected to be a descendant of 129 * dalvik.system.BaseDexClassLoader. We modify its 130 * dalvik.system.DexPathList pathList field to append additional DEX 131 * file entries. 132 */ 133 ClassLoader loader; 134 try { 135 loader = context.getClassLoader(); 136 } catch (RuntimeException e) { 137 /* Ignore those exceptions so that we don't break tests relying on Context like 138 * a android.test.mock.MockContext or a android.content.ContextWrapper with a 139 * null base Context. 140 */ 141 Log.w(TAG, "Failure while trying to obtain Context class loader. " + 142 "Must be running in test mode. Skip patching.", e); 143 return; 144 } 145 if (loader == null) { 146 // Note, the context class loader is null when running Robolectric tests. 147 Log.e(TAG, 148 "Context class loader is null. Must be running in test mode. " 149 + "Skip patching."); 150 return; 151 } 152 153 File dexDir = new File(context.getFilesDir(), SECONDARY_FOLDER_NAME); 154 List<File> files = MultiDexExtractor.load(applicationInfo, dexDir); 155 if (!files.isEmpty()) { 156 if (Build.VERSION.SDK_INT >= 19) { 157 V19.install(loader, files, dexDir); 158 } else if (Build.VERSION.SDK_INT >= 14) { 159 V14.install(loader, files, dexDir); 160 } else { 161 V4.install(loader, files); 162 } 163 } 164 } 165 166 } catch (Exception e) { 167 Log.e(TAG, "Multidex installation failure", e); 168 throw new RuntimeException("Multi dex installation failed (" + e.getMessage() + ")."); 169 } 170 } 171 172 /** 173 * Locates a given field anywhere in the class inheritance hierarchy. 174 * 175 * @param instance an object to search the field into. 176 * @param name field name 177 * @return a field object 178 * @throws NoSuchFieldException if the field cannot be located 179 */ 180 private static Field findField(Object instance, String name) throws NoSuchFieldException { 181 for (Class<?> clazz = instance.getClass(); clazz != null; clazz = clazz.getSuperclass()) { 182 try { 183 Field field = clazz.getDeclaredField(name); 184 185 186 if (!field.isAccessible()) { 187 field.setAccessible(true); 188 } 189 190 return field; 191 } catch (NoSuchFieldException e) { 192 // ignore and search next 193 } 194 } 195 196 throw new NoSuchFieldException("Field " + name + " not found in " + instance.getClass()); 197 } 198 199 /** 200 * Locates a given method anywhere in the class inheritance hierarchy. 201 * 202 * @param instance an object to search the method into. 203 * @param name method name 204 * @param parameterTypes method parameter types 205 * @return a method object 206 * @throws NoSuchMethodException if the method cannot be located 207 */ 208 private static Method findMethod(Object instance, String name, Class<?>... parameterTypes) 209 throws NoSuchMethodException { 210 for (Class<?> clazz = instance.getClass(); clazz != null; clazz = clazz.getSuperclass()) { 211 try { 212 Method method = clazz.getDeclaredMethod(name, parameterTypes); 213 214 215 if (!method.isAccessible()) { 216 method.setAccessible(true); 217 } 218 219 return method; 220 } catch (NoSuchMethodException e) { 221 // ignore and search next 222 } 223 } 224 225 throw new NoSuchMethodException("Method " + name + " with parameters " + 226 Arrays.asList(parameterTypes) + " not found in " + instance.getClass()); 227 } 228 229 /** 230 * Replace the value of a field containing a non null array, by a new array containing the 231 * elements of the original array plus the elements of extraElements. 232 * @param instance the instance whose field is to be modified. 233 * @param fieldName the field to modify. 234 * @param extraElements elements to append at the end of the array. 235 */ 236 private static void expandFieldArray(Object instance, String fieldName, 237 Object[] extraElements) throws NoSuchFieldException, IllegalArgumentException, 238 IllegalAccessException { 239 Field jlrField = findField(instance, fieldName); 240 Object[] original = (Object[]) jlrField.get(instance); 241 Object[] combined = (Object[]) Array.newInstance( 242 original.getClass().getComponentType(), original.length + extraElements.length); 243 System.arraycopy(original, 0, combined, 0, original.length); 244 System.arraycopy(extraElements, 0, combined, original.length, extraElements.length); 245 jlrField.set(instance, combined); 246 } 247 248 /** 249 * Installer for platform versions 19. 250 */ 251 private static final class V19 { 252 253 private static void install(ClassLoader loader, List<File> additionalClassPathEntries, 254 File optimizedDirectory) 255 throws IllegalArgumentException, IllegalAccessException, 256 NoSuchFieldException, InvocationTargetException, NoSuchMethodException { 257 /* The patched class loader is expected to be a descendant of 258 * dalvik.system.BaseDexClassLoader. We modify its 259 * dalvik.system.DexPathList pathList field to append additional DEX 260 * file entries. 261 */ 262 Field pathListField = findField(loader, "pathList"); 263 Object dexPathList = pathListField.get(loader); 264 ArrayList<IOException> suppressedExceptions = new ArrayList<IOException>(); 265 expandFieldArray(dexPathList, "dexElements", makeDexElements(dexPathList, 266 new ArrayList<File>(additionalClassPathEntries), optimizedDirectory, 267 suppressedExceptions)); 268 if (suppressedExceptions.size() > 0) { 269 for (IOException e : suppressedExceptions) { 270 Log.w(TAG, "Exception in makeDexElement", e); 271 } 272 Field suppressedExceptionsField = 273 findField(loader, "dexElementsSuppressedExceptions"); 274 IOException[] dexElementsSuppressedExceptions = 275 (IOException[]) suppressedExceptionsField.get(loader); 276 277 if (dexElementsSuppressedExceptions == null) { 278 dexElementsSuppressedExceptions = 279 suppressedExceptions.toArray( 280 new IOException[suppressedExceptions.size()]); 281 } else { 282 IOException[] combined = 283 new IOException[suppressedExceptions.size() + 284 dexElementsSuppressedExceptions.length]; 285 suppressedExceptions.toArray(combined); 286 System.arraycopy(dexElementsSuppressedExceptions, 0, combined, 287 suppressedExceptions.size(), dexElementsSuppressedExceptions.length); 288 dexElementsSuppressedExceptions = combined; 289 } 290 291 suppressedExceptionsField.set(loader, dexElementsSuppressedExceptions); 292 } 293 } 294 295 /** 296 * A wrapper around 297 * {@code private static final dalvik.system.DexPathList#makeDexElements}. 298 */ 299 private static Object[] makeDexElements( 300 Object dexPathList, ArrayList<File> files, File optimizedDirectory, 301 ArrayList<IOException> suppressedExceptions) 302 throws IllegalAccessException, InvocationTargetException, 303 NoSuchMethodException { 304 Method makeDexElements = 305 findMethod(dexPathList, "makeDexElements", ArrayList.class, File.class, 306 ArrayList.class); 307 308 return (Object[]) makeDexElements.invoke(dexPathList, files, optimizedDirectory, 309 suppressedExceptions); 310 } 311 } 312 313 /** 314 * Installer for platform versions 14, 15, 16, 17 and 18. 315 */ 316 private static final class V14 { 317 318 private static void install(ClassLoader loader, List<File> additionalClassPathEntries, 319 File optimizedDirectory) 320 throws IllegalArgumentException, IllegalAccessException, 321 NoSuchFieldException, InvocationTargetException, NoSuchMethodException { 322 /* The patched class loader is expected to be a descendant of 323 * dalvik.system.BaseDexClassLoader. We modify its 324 * dalvik.system.DexPathList pathList field to append additional DEX 325 * file entries. 326 */ 327 Field pathListField = findField(loader, "pathList"); 328 Object dexPathList = pathListField.get(loader); 329 expandFieldArray(dexPathList, "dexElements", makeDexElements(dexPathList, 330 new ArrayList<File>(additionalClassPathEntries), optimizedDirectory)); 331 } 332 333 /** 334 * A wrapper around 335 * {@code private static final dalvik.system.DexPathList#makeDexElements}. 336 */ 337 private static Object[] makeDexElements( 338 Object dexPathList, ArrayList<File> files, File optimizedDirectory) 339 throws IllegalAccessException, InvocationTargetException, 340 NoSuchMethodException { 341 Method makeDexElements = 342 findMethod(dexPathList, "makeDexElements", ArrayList.class, File.class); 343 344 return (Object[]) makeDexElements.invoke(dexPathList, files, optimizedDirectory); 345 } 346 } 347 348 /** 349 * Installer for platform versions 4 to 13. 350 */ 351 private static final class V4 { 352 private static void install(ClassLoader loader, List<File> additionalClassPathEntries) 353 throws IllegalArgumentException, IllegalAccessException, 354 NoSuchFieldException, IOException { 355 /* The patched class loader is expected to be a descendant of 356 * dalvik.system.DexClassLoader. We modify its 357 * fields mPaths, mFiles, mZips and mDexs to append additional DEX 358 * file entries. 359 */ 360 int extraSize = additionalClassPathEntries.size(); 361 362 Field pathField = findField(loader, "path"); 363 364 StringBuilder path = new StringBuilder((String) pathField.get(loader)); 365 String[] extraPaths = new String[extraSize]; 366 File[] extraFiles = new File[extraSize]; 367 ZipFile[] extraZips = new ZipFile[extraSize]; 368 DexFile[] extraDexs = new DexFile[extraSize]; 369 for (ListIterator<File> iterator = additionalClassPathEntries.listIterator(); 370 iterator.hasNext();) { 371 File additionalEntry = iterator.next(); 372 String entryPath = additionalEntry.getAbsolutePath(); 373 path.append(':').append(entryPath); 374 int index = iterator.previousIndex(); 375 extraPaths[index] = entryPath; 376 extraFiles[index] = additionalEntry; 377 extraZips[index] = new ZipFile(additionalEntry); 378 extraDexs[index] = DexFile.loadDex(entryPath, entryPath + ".dex", 0); 379 } 380 381 pathField.set(loader, path.toString()); 382 expandFieldArray(loader, "mPaths", extraPaths); 383 expandFieldArray(loader, "mFiles", extraFiles); 384 expandFieldArray(loader, "mZips", extraZips); 385 expandFieldArray(loader, "mDexs", extraDexs); 386 } 387 } 388 389} 390