Dex替换

/**
 *  dex注入，优先使用自定义dex中的类
 *
 * @param path
 * @param base
 */
private void InjectDex(String path, Context base) {
    //添加自定义加载路径
    //思路：获取类加载路径表，将自己的插在最前面
    try {
        Field pathListField = BaseDexClassLoader.class.getDeclaredField("pathList");
        pathListField.setAccessible(true);
        Field dexElementsField = Class.forName("dalvik.system.DexPathList").getDeclaredField("dexElements");
        dexElementsField.setAccessible(true);
        Object pElements = dexElementsField.get(pathListField.get(base.getClassLoader()));
        //关键点1，生成自定义dexElements
        Object dElements = dexElementsField.get(pathListField.get(new DexClassLoader(path, null, null, null)));
        int pLen = Array.getLength(pElements);
        int dLen = Array.getLength(dElements);
        //关键点2，插入dexElements
        Object mergeElements = Array.newInstance(pElements.getClass().getComponentType(), pLen + dLen);
        int mLen = pLen + dLen;
        for (int i = 0; i < mLen; i++) {
            if (i < dLen) {
                Array.set(mergeElements, i, Array.get(dElements, i));
            } else {
                Array.set(mergeElements, i, Array.get(pElements, i - dLen));
            }
        }
        dexElementsField.set(pathListField.get(base.getClassLoader()), mergeElements);
    } catch (Exception e) {
        e.printStackTrace();
    }
}



/**
 * so注入，添加自定义so库路径
 *
 * @param path
 * @param base
 */
private void InjectSo(String path, Context base) {
    try {
        Field pathListField = BaseDexClassLoader.class.getDeclaredField("pathList");
        pathListField.setAccessible(true);
        Field nativeLibraryPathElementsField = Class.forName("dalvik.system.DexPathList").getDeclaredField("nativeLibraryPathElements");
        nativeLibraryPathElementsField.setAccessible(true);
        Object nativeElements = nativeLibraryPathElementsField.get(pathListField.get(base.getClassLoader()));
        int len = Array.getLength(nativeElements);
        Object mergeElements = Array.newInstance(nativeElements.getClass().getComponentType(), len + 1);
        //生成并添加自定义nativeLibraryPathElement
        Array.set(mergeElements, 0, Class.forName("dalvik.system.DexPathList$Element").getConstructor(File.class, boolean.class, File.class, DexFile.class).newInstance(new File(path), true, null, null));
        for (int i = 1; i <= len; i++) {
            Array.set(mergeElements, i, Array.get(nativeElements, i - 1));
        }
        nativeLibraryPathElementsField.set(pathListField.get(base.getClassLoader()), mergeElements);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

参考其他人的文章，再借鉴这个代码，一定能OK