请问android app如何启动DexClassLoader动态加载的jar包中定义的service

Question

架构需求就是这样，Service类定义在一个Jar包插件，通过网络下载或者push到SD卡中，然后要求Service在新进程中启动。
运行时出现找不到Service类的错误，然后程序错误崩溃：
Causedby:java.lang.ClassNotFoundException:Didn'tfindclassJarService
贴个简单代码示例吧
主Activity就是loadSD卡上的jar包，反射获取类名，intent启动service
publicclassMainActivityextendsActionBarActivity{
privatefinalStringTAG="MainActivity";
@Override
protectedvoidonCreate(BundlesavedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.i(TAG,"onCreate");
ClassLoaderdexLoader=newDexClassLoader("/sdcard/jarservicetest.jar",getCacheDir().getAbsolutePath(),null,getClassLoader());
//ClassLoaderdexLoader=getClassLoader();
try{
Log.i(TAG,"try");
ClassactivityClass=dexLoader.loadClass("com.example.jarservicetest.JarService");
Intentintent=newIntent(this,activityClass);
startService(intent);
}catch(ClassNotFoundExceptione){
Log.i(TAG,"catch");
//TODOAuto-generatedcatchblock
e.printStackTrace();
}
}
}
Service就一空壳
publicclassJarServiceextendsService{
privatefinalStringTAG="JARSERVICE";
@Override
publicvoidonCreate(){
//TODOAuto-generatedmethodstub
Log.i(TAG,"onCreate");
super.onCreate();
}
@Override
publicvoidonDestroy(){
//TODOAuto-generatedmethodstub
super.onDestroy();
}
@Override
publicIBinderonBind(Intentarg0){
//TODOAuto-generatedmethodstub
returnnull;
}
}
Manifest文件中声明了Service
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme">
android:name=".MainActivity"
android:label="@string/app_name">
请教达人们，面对这种需求，有啥解决办法？

Answer 1

检查下jarservicetest.jar文件里包含的是class文件还是dex文件拿sdcard路径的时候，用Environment.getExternalStorageDirectory()