文章目录
一、Instrumentation 源码分析
二、Instrumentation 创建 Application 相关的部分源码
dex 解密时 , 需要将 代理 Application 替换为 真实 Application ; 替换 Application 首先要理解系统如何注册应用的 Application 的 ;
一、Instrumentation 源码分析
Instrumentation.java 类参考源码 : 6.0.1_r16/xref/frameworks/base/core/java/android/app/Instrumentation.java 常用方法 :
newActivity : 创建 Activity ;
newApplication : 创建 Application ;
sendKeyDownUpSync : 模拟按键 ;
上一篇博客中讲解了 LoadedApk 中调用 makeApplication 方法创建应用的 Application , 在该方法中通过调用 Instrumentation 的 newApplication 方法创建 Application ;
在 Application newApplication(ClassLoader cl, String className, Context context) 中 , 调用了其重载函数 Application newApplication(Class<?> clazz, Context context) , 前者包含 3 33 个参数 , 后者包含 2 22 个参数 ;
public Application newApplication(ClassLoader cl, String className, Context context) throws InstantiationException, IllegalAccessException, ClassNotFoundException { return newApplication(cl.loadClass(className), context); }
完整源码参考 : 6.0.1_r16/xref/frameworks/base/core/java/android/app/Instrumentation.java
在 Application newApplication(Class<?> clazz, Context context) 函数中就执行了两行代码 , 调用 clazz.newInstance() 反射创建 Application 对象 , 然后调用 Application 的 attach 函数 , 传入 Context 上下文对象 ;
static public Application newApplication(Class<?> clazz, Context context) throws InstantiationException, IllegalAccessException, ClassNotFoundException { Application app = (Application)clazz.newInstance(); app.attach(context); return app; }
完整源码参考 : 6.0.1_r16/xref/frameworks/base/core/java/android/app/Instrumentation.java
Application 的 void attach(Context context) 方法中 , 调用了 attachBaseContext(context) 方法 , 由此可以看出在 Application 中 , attachBaseContext 函数要比 onCreate 先执行 ;
在 Application 使用反射方法创建出来之后 , 马上就会调用 attach 方法 , 进而先调用 attachBaseContext 方法 ;
public class Application extends ContextWrapper implements ComponentCallbacks2 { /** * @hide */ /* package */ final void attach(Context context) { attachBaseContext(context); mLoadedApk = ContextImpl.getImpl(context).mPackageInfo; } }
源码参考 : xref/frameworks/base/core/java/android/app/Application.java
二、Instrumentation 创建 Application 相关的部分源码
public class Instrumentation { /** * Perform instantiation of the process's {@link Application} object. The * default implementation provides the normal system behavior. * * @param cl The ClassLoader with which to instantiate the object. * @param className The name of the class implementing the Application * object. * @param context The context to initialize the application with * * @return The newly instantiated Application object. */ public Application newApplication(ClassLoader cl, String className, Context context) throws InstantiationException, IllegalAccessException, ClassNotFoundException { return newApplication(cl.loadClass(className), context); } /** * Perform instantiation of the process's {@link Application} object. The * default implementation provides the normal system behavior. * * @param clazz The class used to create an Application object from. * @param context The context to initialize the application with * * @return The newly instantiated Application object. */ static public Application newApplication(Class<?> clazz, Context context) throws InstantiationException, IllegalAccessException, ClassNotFoundException { Application app = (Application)clazz.newInstance(); app.attach(context); return app; } }
完整源码参考 : 6.0.1_r16/xref/frameworks/base/core/java/android/app/Instrumentation.java
