Generic DAO & Service

/* ################################# DAO ################################ */
package net.example.com.dao;

import java.util.List;

public interface GenericDao<T> {
    public T findById(int id);
    public List<T> findAll();
    public void update(T entity);
    public void save(T entity);
    public void delete(T entity);
}

/* ------------------------------------------------------ */

package net.example.com.dao;

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

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Scope;

@Scope("prototype")
public abstract class GenericHibernateDaoImpl<T extends Serializable> implements GenericDao<T> {

    private Class<T> clazz;

    @Autowired
    private SessionFactory sessionFactory;

    public final void setClazz(Class<T> clazzToSet) {
        this.clazz = clazzToSet;
    }

    @SuppressWarnings("unchecked")
    public T findById(int id) {
        return (T) getCurrentSession().get(clazz, id);
    }

    @SuppressWarnings("unchecked")
    public List<T> findAll() {
        return getCurrentSession().createQuery("FROM " + clazz.getName()).list();
    }

    public void update(T entity) {
        getCurrentSession().update(entity);
    }

    public void save(T entity) {
        getCurrentSession().save(entity);
    }

    public void delete(T entity) {
        getCurrentSession().delete(entity);
    }

    protected final Session getCurrentSession(){
        return sessionFactory.getCurrentSession();
    }
}

/* ------------------------------------------------------ */

package net.example.com.dao;

import net.example.com.entity.Country;

public interface CountryDao extends GenericDao<Country> {

    public Country findByName(String name);
    public Country findByCode(String code);

}

/* ------------------------------------------------------ */

package net.example.com.dao;

import org.springframework.stereotype.Repository;

import net.example.com.entity.Country;

@Repository
public class CountryDaoImpl extends GenericHibernateDaoImpl<Country> implements CountryDao {

    @Override
    public Country findByName(String name) {
        return (Country) getCurrentSession()
                .createQuery("FROM Country WHERE name = :name")
                .setString("name", name).uniqueResult();
    }

    @Override
    public Country findByCode(String code) {
        return (Country) getCurrentSession()
                .createQuery("FROM Country WHERE code = :code")
                .setString("code", code).uniqueResult();
    }

}

/* ################################# DAO ################################ */



/* ################################# SERVICE ################################ */

package net.example.com.service;

import java.util.List;

public interface GenericManager<T> { // GenericManager<T> = GenericDao<T>

    public T findById(int id);
    public List<T> findAll();
    public void update(T entity);
    public void save(T entity);
    public void delete(T entity);
}

/* ------------------------------------------------------ */

package net.example.com.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import net.example.com.dao.GenericDao;

@Service
public abstract class GenericManagerImpl<T> implements GenericManager<T> {

    @Autowired
    protected GenericDao<T> dao;

    @Override
    public T findById(int id) {
        return dao.findById(id);
    }

    @Override
    public List<T> findAll() {
        return dao.findAll();
    }

    @Override
    public void update(T entity) {
        dao.update(entity);
    }

    @Override
    public void save(T entity) {
        dao.save(entity);
    }

    @Override
    public void delete(T entity) {
        dao.delete(entity);
    }
}
/* ------------------------------------------------------ */

package net.example.com.dao;

import net.example.com.entity.Country;

public interface CountryManager extends GenericDao<Country> { // CountryManager = CountryDao

    public Country findByName(String name);
    public Country findByCode(String code);
}

/* ------------------------------------------------------ */

package net.example.com.service;

import java.util.List;

import javax.transaction.Transactional;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import net.example.com.dao.CountryDao;
import net.example.com.entity.Country;

@Service
@Transactional
public class CountryManagerImpl extends GenericManagerImpl<Country> implements CountryManager {

    @Override
    public List<Country> findAll() {
        return dao.findAll();
    }

    public Country findById(int id) {
        return dao.findById(id);
    }

    @Override
    public Country findByName(String name) {
        return dao.findByName(name); // nevidi to metodu findByName !!!!!!!!!
    }

    @Override
    public Country findByCode(String code) {
        return dao.findByCode(code); // nevidi to metodu findByCode !!!!!!!!!
    }

    @Override
    public void save(Country country) {
        dao.save(country);
    }

    @Override
    public void delete(Country country) {
        dao.delete(country);
    }

    @Override
    public void update(Country country) {
        dao.update(country);
    }

}

/* ------------------------------------------------------ */

/* ################################# SERVICE ################################ */