通过反射机制拿到被隐藏的类(获取应用程序的缓存大小)

pm=getPackageManager();
        //拿到该类中所有的方法名
        
         try {
            Method method=PackageManager.class.getMethod("getPackageSizeInfo", new Class[]{String.class,IPackageStatsObserver.class});
             method.invoke(pm, new Object[]{"cn.itcast.mobilesafe",new IPackageStatsObserver.Stub() {
                
                public void onGetStatsCompleted(PackageStats pStats, boolean succeeded)
                        throws RemoteException {
                    long cacheSize=pStats.cacheSize;    
                    long codeSize=pStats.codeSize;
                    long dataSize=pStats.dataSize;
                    System.out.println("手机卫士的大小是多少呢"+cacheSize+codeSize+dataSize);
                }
            }});
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }