public static final List<Class<?>> getClassesFromPackage(Context ctx, String pkgName) {

         List<Class<?>> rtnList = new ArrayList<Class<?>>();

         String[] apkPaths = ctx.getApplicationInfo().splitSourceDirs;// 获得所有的APK的路径

         DexFile dexfile = null;

         Enumeration<String> entries = null;

         String name = null;

         for (String apkPath : apkPaths) {

             try {

                 dexfile = new DexFile(apkPath);// 获得编译后的dex文件

                 entries = dexfile.entries();// 获得编译后的dex文件中的所有class

                 while (entries.hasMoreElements()) {

                     name = (String) entries.nextElement();

                     if (name.startsWith(pkgName)) {// 判断类的包名是否符合

                         rtnList.add(Class.forName(name));

                     }

                 }

             } catch (ClassNotFoundException | IOException e) {

             } finally {

                 try {

                     if (dexfile != null) {

                         dexfile.close();

                     }

                 } catch (IOException e) {

                 }

             }

         }

         return rtnList;

     }