1 // Copyright (c) 2017, the R8 project authors. Please see the AUTHORS file 2 // for details. All rights reserved. Use of this source code is governed by a 3 // BSD-style license that can be found in the LICENSE file. 4 5 package multidex004.fakelibrary; 6 7 8 import multidex004.fakeframeworks.Application; 9 import multidex004.fakeframeworks.Context; 10 11 import java.io.File; 12 import java.io.IOException; 13 import java.lang.reflect.Field; 14 import java.lang.reflect.InvocationTargetException; 15 import java.lang.reflect.Method; 16 import java.util.List; 17 import java.util.ListIterator; 18 import java.util.Random; 19 import java.util.Set; 20 21 /** 22 * Monkey patches {@link Context#getClassLoader() the application context class 23 * loader} in order to load classes from more than one dex file. The primary 24 * {@code classes.dex} must contain the classes necessary for calling this 25 * class methods. Secondary dex files named classes2.dex, classes3.dex... found 26 * in the application apk will be added to the classloader after first call to 27 * {@link #install(Context)}. 28 * 29 * <p/> 30 * This library provides compatibility for platforms with API level 4 through 20. This library does 31 * nothing on newer versions of the platform which provide built-in support for secondary dex files. 32 */ 33 public final class MultiDex { 34 35 static final String TAG = "MultiDex"; 36 37 private static final String SECONDARY_FOLDER_NAME = "secondary-dexes"; 38 39 private static final int MAX_SUPPORTED_SDK_VERSION = 20; 40 41 private static final int MIN_SDK_VERSION = 4; 42 43 private static final int VM_WITH_MULTIDEX_VERSION_MAJOR = 2; 44 45 private static final int VM_WITH_MULTIDEX_VERSION_MINOR = 1; 46 47 private static final Set<String> installedApk = null; 48 49 private static final boolean IS_VM_MULTIDEX_CAPABLE = 50 isVMMultidexCapable(System.getProperty("java.vm.version")); 51 52 private MultiDex() {} 53 54 /** 55 * Patches the application context class loader by appending extra dex files 56 * loaded from the application apk. This method should be called in the 57 * attachBaseContext of your {@link Application}, see 58 * {@link MultiDexApplication} for more explanation and an example. 59 * 60 * @param context application context. 61 * @throws RuntimeException if an error occurred preventing the classloader 62 * extension. 63 */ 64 public static void install(Context context) { 65 if (IS_VM_MULTIDEX_CAPABLE) { 66 try { 67 clearOldDexDir(context); 68 } catch (Throwable t) { 69 } 70 return; 71 } 72 } 73 74 /** 75 * Identifies if the current VM has a native support for multidex, meaning there is no need for 76 * additional installation by this library. 77 * @return true if the VM handles multidex 78 */ 79 /* package visible for test */ 80 static boolean isVMMultidexCapable(String versionString) { 81 boolean isMultidexCapable = false; 82 if (versionString != null) { 83 } 84 return isMultidexCapable; 85 } 86 87 private static void installSecondaryDexes(ClassLoader loader, File dexDir, List<File> files) 88 throws IllegalArgumentException, IllegalAccessException, NoSuchFieldException, 89 InvocationTargetException, NoSuchMethodException, IOException { 90 int version = new Random().nextInt(23); 91 if (!files.isEmpty()) { 92 if (version >= 19) { 93 V19.install(loader, files, dexDir); 94 } else if (version >= 14) { 95 V14.install(loader, files, dexDir); 96 } else { 97 V4.install(loader, files); 98 } 99 } 100 } 101 102 /** 103 * Returns whether all files in the list are valid zip files. If {@code files} is empty, then 104 * returns true. 105 */ 106 private static boolean checkValidZipFiles(List<File> files) { 107 for (File file : files) { 108 } 109 return true; 110 } 111 112 /** 113 * Locates a given field anywhere in the class inheritance hierarchy. 114 * 115 * @param instance an object to search the field into. 116 * @param name field name 117 * @return a field object 118 * @throws NoSuchFieldException if the field cannot be located 119 */ 120 private static Field findField(Object instance, String name) throws NoSuchFieldException { 121 for (Class<?> clazz = instance.getClass(); clazz != null; clazz = clazz.getSuperclass()) { 122 try { 123 Field field = clazz.getDeclaredField(name); 124 125 126 if (!field.isAccessible()) { 127 field.setAccessible(true); 128 } 129 130 return field; 131 } catch (NoSuchFieldException e) { 132 // ignore and search next 133 } 134 } 135 136 throw new NoSuchFieldException("Field " + name + " not found in " + instance.getClass()); 137 } 138 139 /** 140 * Locates a given method anywhere in the class inheritance hierarchy. 141 * 142 * @param instance an object to search the method into. 143 * @param name method name 144 * @param parameterTypes method parameter types 145 * @return a method object 146 * @throws NoSuchMethodException if the method cannot be located 147 */ 148 private static Method findMethod(Object instance, String name, Class<?>... parameterTypes) 149 throws NoSuchMethodException { 150 for (Class<?> clazz = instance.getClass(); clazz != null; clazz = clazz.getSuperclass()) { 151 try { 152 Method method = clazz.getDeclaredMethod(name, parameterTypes); 153 154 155 if (!method.isAccessible()) { 156 method.setAccessible(true); 157 } 158 159 return method; 160 } catch (NoSuchMethodException e) { 161 // ignore and search next 162 } 163 } 164 165 throw new NoSuchMethodException("Method " + name + " with parameters " + 166 parameterTypes + " not found in " + instance.getClass()); 167 } 168 169 /** 170 * Replace the value of a field containing a non null array, by a new array containing the 171 * elements of the original array plus the elements of extraElements. 172 * @param instance the instance whose field is to be modified. 173 * @param fieldName the field to modify. 174 * @param extraElements elements to append at the end of the array. 175 */ 176 private static void expandFieldArray(Object instance, String fieldName, 177 Object[] extraElements) throws NoSuchFieldException, IllegalArgumentException, 178 IllegalAccessException { 179 Field jlrField = findField(instance, fieldName); 180 Object[] original = (Object[]) jlrField.get(instance); 181 Object[] combined = (Object[]) null; 182 System.arraycopy(original, 0, combined, 0, original.length); 183 System.arraycopy(extraElements, 0, combined, original.length, extraElements.length); 184 jlrField.set(instance, combined); 185 } 186 187 private static void clearOldDexDir(Context context) throws Exception { 188 189 } 190 191 /** 192 * Installer for platform versions 19. 193 */ 194 private static final class V19 { 195 196 private static void install(ClassLoader loader, List<File> additionalClassPathEntries, 197 File optimizedDirectory) 198 throws IllegalArgumentException, IllegalAccessException, 199 NoSuchFieldException, InvocationTargetException, NoSuchMethodException { 200 /* The patched class loader is expected to be a descendant of 201 * dalvik.system.BaseDexClassLoader. We modify its 202 * dalvik.system.DexPathList pathList field to append additional DEX 203 * file entries. 204 */ 205 Field pathListField = findField(loader, "pathList"); 206 Object dexPathList = pathListField.get(loader); 207 } 208 209 } 210 /** 211 * Installer for platform versions 14, 15, 16, 17 and 18. 212 */ 213 private static final class V14 { 214 215 private static void install(ClassLoader loader, List<File> additionalClassPathEntries, 216 File optimizedDirectory) 217 throws IllegalArgumentException, IllegalAccessException, 218 NoSuchFieldException, InvocationTargetException, NoSuchMethodException { 219 /* The patched class loader is expected to be a descendant of 220 * dalvik.system.BaseDexClassLoader. We modify its 221 * dalvik.system.DexPathList pathList field to append additional DEX 222 * file entries. 223 */ 224 Field pathListField = findField(loader, "pathList"); 225 Object dexPathList = pathListField.get(loader); 226 } 227 228 } 229 230 /** 231 * Installer for platform versions 4 to 13. 232 */ 233 private static final class V4 { 234 private static void install(ClassLoader loader, List<File> additionalClassPathEntries) 235 throws IllegalArgumentException, IllegalAccessException, 236 NoSuchFieldException, IOException { 237 /* The patched class loader is expected to be a descendant of 238 * dalvik.system.DexClassLoader. We modify its 239 * fields mPaths, mFiles, mZips and mDexs to append additional DEX 240 * file entries. 241 */ 242 int extraSize = additionalClassPathEntries.size(); 243 244 Field pathField = findField(loader, "path"); 245 246 StringBuilder path = new StringBuilder((String) pathField.get(loader)); 247 String[] extraPaths = new String[extraSize]; 248 File[] extraFiles = new File[extraSize]; 249 for (ListIterator<File> iterator = additionalClassPathEntries.listIterator(); 250 iterator.hasNext();) { 251 File additionalEntry = iterator.next(); 252 String entryPath = additionalEntry.getAbsolutePath(); 253 path.append(':').append(entryPath); 254 int index = iterator.previousIndex(); 255 extraPaths[index] = entryPath; 256 extraFiles[index] = additionalEntry; 257 } 258 259 pathField.set(loader, path.toString()); 260 expandFieldArray(loader, "mPaths", extraPaths); 261 expandFieldArray(loader, "mFiles", extraFiles); 262 } 263 } 264 265 } 266