(List<Customer>)(Object)list; 
将List<Object>强制转换成Object，然后再转换为实体集合！
地址：https://stackoverflow.com/questions/1917844/how-to-cast-listobject-to-listmyclass

Critics say that such casting indicates something wrong with your code; you should be able to tweak your type declarations to avoid it. But Java generics is too complicated, and it is not perfect. Sometimes you just don‘t know if there is a pretty solution to satisfy the compiler, even though you know very well the runtime types and you know what you are trying to do is safe. In that case, just do the crude casting as needed, so you can leave work for home.