一個支持泛型的DAO接口類

 
/**


Defines a generic DAO interface.

@author javier

@param <T>
The type this DAO handles.
@param <ID>
The type of the id of the handled entity.
*/
public interface DAOInterface<T, ID extends Serializable>
{
/**

Makes the given entity persistent.
*
@param entity The entity to persist.
@throws When the quota of instances for that entity was exceeded.
*/
void makePersistent(T entity) throws QuotaExceededException;

/**

Makes the given entity transient.
*
@param entity The entity to make transient.
*/
void makeTransient(T entity);

/**

@return the number of matching entities.
*/
int count(Filter filter);

/**

Returns a single entity which has the given ID or throws an
<code>EntityNotFoundException</code> if no matching entity is found.

@param id
The ID of the entity to return.
@return The entity.
*/
T findById(ID id) throws EntityNotFoundException;

/**

Returns all matching entities of type <code>T</code>.

@param filter
The <code>Filter</code> to use.
*
@return An ordered <code>List</code> with the entities.
*/
List<T> find(Filter filter);

/**

Returns all entities of type <code>T</code>.

@return An ordered <code>List</code> with the entities.
*/
List<T> findAll();

/**

Returns a page of entities.

@param filter
The <code>Filter</code> to use.
@param startRow
The offset.
@param pageSize
The number of entities to return.
*
@return A <code>Pair</code> of values. The first value is the
<code>List</code> of entities and the second one if the total
number of existing entities.
*/
Pair<List<T>, Integer> findPaged(Filter filter, int startRow, int pageSize);

/**

Flushing is the process of synchronising the underlying persistent
store with persistable state held in memory. 
*/
void flush();
}



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