package com.xxx.dao;

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

import javax.annotation.Resource;

import org.hibernate.Session;
import org.hibernate.SessionFactory;

import com.google.common.base.Preconditions;

public class BaseDaoImpl<T extends Serializable> implements IBaseDao<T> {
	private Class<T> clazz;
	@Resource(name = "sessionFactory")
	private SessionFactory sessionFactory;

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

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

	public T findOne(long id) {
		return (T) getSession().get(clazz, id);
	}

	public List<T> findAll() {
		return getSession().createQuery("from " + clazz.getName()).list();
	}

	public void addOne(T entity) {
		Preconditions.checkNotNull(entity);
		getSession().saveOrUpdate(entity);
	}

	public void update(T entity) {
		Preconditions.checkNotNull(entity);
		getSession().update(entity);
	}

	public void deleteById(long entityId) {
		T t = findOne(entityId);
		Preconditions.checkNotNull(t);
		getSession().delete(t);
	}

}