android - 静默卸载 apk 异常---(java.lang.AbstractMethodError : abstract method not implemented)

Question

我正在开发一个支持静默卸载其他 apk 的应用程序。我的设备已 root，应用程序位于/system/app 下，通过反射我可以使用 deletePackage 方法来实现它。但是在deletePackage方法的实现中，出现异常，异常信息如下:

09-20 10:16:02.242: E/JavaBinder(1943): *** Uncaught remote exception!  (Exceptions are not yet supported across processes.)
09-20 10:16:02.242: E/JavaBinder(1943): java.lang.AbstractMethodError: abstract method not implemented
09-20 10:16:02.242: E/JavaBinder(1943):     at android.content.pm.IPackageDeleteObserver$Stub.packageDeleted(IPackageDeleteObserver.java)
09-20 10:16:02.242: E/JavaBinder(1943):     at android.content.pm.IPackageDeleteObserver$Stub.onTransact(IPackageDeleteObserver.java:57)
09-20 10:16:02.242: E/JavaBinder(1943):     at android.os.Binder.execTransact(Binder.java:338)
09-20 10:16:02.242: E/JavaBinder(1943):     at dalvik.system.NativeStart.run(Native Method)
09-20 10:16:02.242: W/dalvikvm(1943): threadid=9: thread exiting with uncaught exception (group=0x40a461f8)
09-20 10:16:02.242: E/AndroidRuntime(1943): FATAL EXCEPTION: Binder Thread #1
09-20 10:16:02.242: E/AndroidRuntime(1943): java.lang.AbstractMethodError: abstract method not implemented
09-20 10:16:02.242: E/AndroidRuntime(1943):     at android.content.pm.IPackageDeleteObserver$Stub.packageDeleted(IPackageDeleteObserver.java)
09-20 10:16:02.242: E/AndroidRuntime(1943):     at android.content.pm.IPackageDeleteObserver$Stub.onTransact(IPackageDeleteObserver.java:57)
09-20 10:16:02.242: E/AndroidRuntime(1943):     at android.os.Binder.execTransact(Binder.java:338)
09-20 10:16:02.242: E/AndroidRuntime(1943):     at dalvik.system.NativeStart.run(Native Method)

相关代码:

public void onBackgroundUninstallClick(View v) {
    PackageDeleteObserver observer = new PackageDeleteObserver();
    if (mPackageManager != null/* && mUninstallPackage != null*/) {
        try {
            mPackageManager.deletePackage("com.example.android.imagedownloader", observer, 0);
        } catch (RemoteException e) {
            e.printStackTrace();
        }
    } 
}

class PackageDeleteObserver extends IPackageDeleteObserver.Stub {
    public void packageDeleted(boolean succeeded) throws RemoteException {
        Log.i(TAG, "packageDeleted");
        Message msg = mHandler.obtainMessage(UNINSTALL_COMPLETE);
        msg.arg1 = succeeded ? SUCCEEDED : FAILED;
        mHandler.sendMessage(msg);
    }
}

IPackageDeleteObserver.aidl code : 

package android.content.pm;

interface IPackageDeleteObserver {
    void packageDeleted(boolean flag);
}

Answer 1

java.lang.AbstractMethodError: abstract method not implemented

某处缺少方法实现。

void packageDeleted(boolean flag);

与

的签名不符

public void packageDeleted(boolean succeeded) throws RemoteException

因为抛出RemoteException

改为

interface IPackageDeleteObserver {
    void packageDeleted(boolean flag) throws RemoteException;
}