替换ClassLoader

替换ClassLoader

package com.bluelesson.dummydex34;​import android.app.Application;import android.content.Context;import android.content.res.AssetManager;import android.util.Log;​import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.lang.reflect.Field;import java.lang.reflect.Method;​import dalvik.system.DexClassLoader;​public class DummyApplication extends Application {​​    @Override    protected void attachBaseContext(Context base) {        super.attachBaseContext(base);​        // 1. 拷贝dex到安装目录下        String path = copyDex("src.dex");        // 2. 使用DexClassLoader，加载dex        DexClassLoader dex = loadDex(path);        // 3. 替换ClassLoader        replaceClassLoader1(dex);   }​​    @Override    public void onCreate() {        super.onCreate();   }​​    // 拷贝指定的文件从assets目录中到/data/data/包名/files中    String copyDex(String dexName) {        // 获取assets目录管理器        AssetManager as = getAssets();        // 合成路径        // getFilesDir返回的就是/data/data/包名/files        String path = getFilesDir() + File.separator + dexName; // File.separator 分隔符        Log.i("15pb-log", path);        try {            // 建立文件流            FileOutputStream out = new FileOutputStream(path);            // 打开文件            InputStream is = as.open(dexName);            // 循环读取文件，拷贝到对应路径            byte[] buffer = new byte[1024];            int len = 0;            while ((len = is.read(buffer)) != -1) {                out.write(buffer, 0, len);           }            // 关闭文件            out.close();​       } catch (IOException e1) {            // TODO Auto-generated catch block            e1.printStackTrace();            return "";       }        return path;   }​    // 得到指定文件的dex加载器    public DexClassLoader loadDex(String path) {        // 建立dex文件的类加载器，返回DexClassLoader对象        DexClassLoader dex = new DexClassLoader(                path,       // dex路径                getCacheDir().toString(),   // 优化以后的文件的路径                null,      // 原生库路径                getClassLoader());          // 父类加载器        return dex;   }​    public void replaceClassLoader1(DexClassLoader dexClassLoader){        try {            // 1. 获取ActivityThead类对象            // android.app.ActivityThread            // 1.1 获取类类型            Class clzActivityThead = Class.forName("android.app.ActivityThread");            // 1.2 获取类方法            Method currentActivityThread = clzActivityThead.getMethod("currentActivityThread",new Class[]{});            // 1.3 调用方法            currentActivityThread.setAccessible(true);            Object objActivityThread = currentActivityThread.invoke(null);​            // 2. 经过类对象获取成员变量mBoundApplication            //clzActivityThead.getDeclaredField()            Field field = clzActivityThead.getDeclaredField("mBoundApplication");            // AppBindData            field.setAccessible(true);            Object data = field.get(objActivityThread);            // 3. 获取mBoundApplication对象中的成员变量info            // 3.1 获取 AppBindData 类类型            Class clzAppBindData = Class.forName("android.app.ActivityThread$AppBindData");            // 3.2 获取成员变量info            Field field1 = clzAppBindData.getDeclaredField("info");            // 3.3 获取对应的值            //LoadedApk            field1.setAccessible(true);            Object info = field1.get(data);            // 4. 获取info对象中的mClassLoader            // 4.1 获取 LoadedApk 类型            Class clzLoadedApk = Class.forName("android.app.LoadedApk");            // 4.2 获取成员变量 mClassLoader            Field field2 = clzLoadedApk.getDeclaredField("mClassLoader");            field2.setAccessible(true);​                                                                                                                                                                                                                                                                    d2.set(info,dexClassLoader);​       } catch (Exception e) {            e.printStackTrace();       }   }}​