allow @NamedQuery and @NamedNativeQuery more control over query execution

[gavinking]

Currently, a @NamedQuery or @NamedNativeQuery may specify query hints using the verbose and stringly-typed annotation @QueryHint.

I propose making certain "hints" available in a typesafe way, for example:

public @interface NamedQuery {
    ...
    FlushModeType flushMode() default AUTO;
    CacheStoreMode cacheStoreMode() default USE;
    CacheRetrieveMode cacheRetrieveMode() default USE;
    int timeout() default -1;
}

In the case of @NamedNativeQuery, it might even be useful to add a way to specify the tables or entities affected by a native query, to allow auto-flush to work correctly:

public @interface NamedNativeQuery {
    ...
    FlushModeType flushMode() default AUTO;
    CacheStoreMode cacheStoreMode() default USE;
    CacheRetrieveMode cacheRetrieveMode() default USE;
    int timeout() default -1;

   // control over auto-flush

    String[] affectedTables() default {};
    Class<?>[] affectedEntities() default {};
}