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java - Avoiding Type Safety Warnings Using Hibernate Query.list()

Is it possible to avoid cast warnings after using createQuery().list?

//Type safety: The expression of type List needs unchecked conversion to conform to List<User>
List<User> user = (List<User>) session.createQuery("select u from User u").list();

I expected to find a method that specified the target object via generic parameter or method parameter such as the following:

List<User> user = session.createQuery("select u from User u").list(User.class);
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The most important thing to remember is that warnings are due to your compiler, not hibernate - you can tell your compiler to ignore unimplemented generics. By using HQL, we are querying for data in a type safe way that, unfortunately, java does not have the ability to verify.

There are a lot of ways to get around the syntactical ugliness of hibernate casting , like :

1) use @suppressWarnings where casting or

2) use the Collections.checkedList method to create the new list.

See also : How to avoid type safety warnings with Hibernate HQL results?


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