package com.opentravelsoft.providers;

import java.io.Serializable;
import java.util.List;
import java.util.Map;

import org.hibernate.criterion.DetachedCriteria;

import com.opentravelsoft.util.PaginationSupport;

/**
 * Generic DAO (Data Access Object) with common methods to CRUD POJOs.
 * 
 * <p>
 * Extend this interface if you want typesafe (no casting necessary) DAO's for
 * your domain objects.
 * 
 * @author <a href="mailto:bwnoll@gmail.com">Bryan Noll</a>
 * @param <T> a type variable
 * @param <PK> the primary key for that type
 */
public interface GenericDao<T, PK extends Serializable>
{

    /**
     * Generic method used to get all objects of a particular type. This is the
     * same as lookup up all rows in a table.
     * 
     * @return List of populated objects
     */
    List<T> getAll();

    /**
     * Gets all records without duplicates.
     * <p>
     * Note that if you use this method, it is imperative that your model
     * classes correctly implement the hashcode/equals methods
     * </p>
     * 
     * @return List of populated objects
     */
    List<T> getAllDistinct();

    /**
     * Generic method to get an object based on class and identifier. An
     * ObjectRetrievalFailureException Runtime Exception is thrown if nothing is
     * found.
     * 
     * @param id the identifier (primary key) of the object to get
     * @return a populated object
     * @see org.springframework.orm.ObjectRetrievalFailureException
     */
    T get(PK id);

    /**
     * Checks for existence of an object of type T using the id arg.
     * 
     * @param id the id of the entity
     * @return - true if it exists, false if it doesn't
     */
    boolean exists(PK id);

    /**
     * Generic method to save an object - handles both update and insert.
     * 
     * @param object the object to save
     * @return the persisted object
     */
    T save(T object);

    /**
     * Generic method to delete an object based on class and id
     * 
     * @param id the identifier (primary key) of the object to remove
     */
    void remove(PK id);

    /**
     * Find a list of records by using a named query
     * 
     * @param queryName query name of the named query
     * @param queryParams a map of the query names and the values
     * @return a list of the records found
     */
    List<T> findByNamedQuery(String queryName, Map<String, Object> queryParams);

    PaginationSupport findPageByCriteria(final DetachedCriteria detachedCriteria);

    PaginationSupport findPageByCriteria(
            final DetachedCriteria detachedCriteria, final int startIndex);

    PaginationSupport findPageByCriteria(
            final DetachedCriteria detachedCriteria, final int pageSize,
            final int startIndex);

    List<T> findAllByCriteria(final DetachedCriteria detachedCriteria);

    int getCountByCriteria(final DetachedCriteria detachedCriteria);
}