@Override public void attachInfo(final Context context, final ProviderInfo info) {
		mShuttleAuthority = info.authority;
		final String host = info.authority.substring(0, info.authority.lastIndexOf(".shuttle"));	// Authority without trailing ".shuttle"
		Users.refreshUsers(context);	// Users may not be ready at this point, due to the parallel nature of provider initialization.
		mTargetAuthority = Users.toId(Users.isOwner() && Users.profile != null ? Users.profile : Users.owner) + "@" + host;		// Add user ID.
		Log.d(TAG, "Target authority: " + mTargetAuthority);
		super.attachInfo(context, info);
	}
This single-user provider serves as a proxy provider, since it can be accessed from any user.

Created by Oasis on 2017/8/29.
fileprovider/src/main/java/com/oasisfeng/island/fileprovider/ShuttleProvider.java