该数据库的扩展名必须是因为它是完全一样的。
此外，我认为你的主要问题是，你指定了错误的包。它必须是根包。尝试：

The db name extension has to be exactly the same as it is. Moreover, I think your main problem is that you specify the wrong package. It has to be the root package. Try that:

private final static String DB_PATH = "data/data/com.jeston.existed/databases/";