hibernate框架BaseDao
做web开发的过程中估计会有80%-90%是和数据库打交道的，因此Dao层起了关键的作用。而每个实体类对应一个dao太麻烦，不能快速的开发。本文 的基本DAO是于hibernate与java的反射机制编写的。虽然网上也有很多不同的写法，各有各的想法么！对不对。
package com.gmxt.baseDao.baseDaoImpl; import java.lang.reflect.ParameterizedType; import java.util.Collections; import java.util.List; import javax.annotation.Resource; import org.hibernate.Query; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.springframework.transaction.annotation.Transactional; import com.gmxt.baseDao.BaseDao; import com.gmxt.common.Pagination; @Transactional @SuppressWarnings("unchecked") public abstract class BaseDaoImpl<T> implements BaseDao<T> { @Resource private SessionFactory sessionFactory; protected Class<T> clazz; public BaseDaoImpl() { ParameterizedType type = (ParameterizedType) this.getClass() .getGenericSuperclass(); this.clazz = (Class) type.getActualTypeArguments()[0]; } public void delete(String id) { Object object = (Object) getSession().get(clazz, id); getSession().delete(object); } public T getById(String id) { return (T) getSession().get(clazz, id); } public List<T> getAll() { return getSession().createQuery("from " + clazz.getSimpleName()).list(); } public List<T> getByIds(String[] ids) { if (ids == null || ids.length == 0) { return Collections.EMPTY_LIST; } return getSession().createQuery( "FROM " + clazz.getSimpleName() + " WHERE id IN(:ids)") .setParameterList("ids", ids).list(); } public int getTotalCount() { int totalCount = ((Long)getSession().createQuery("select count(*) from " + clazz.getSimpleName()).list().get(0)).intValue(); return totalCount; } public String save(T entity) { String id = (String) getSession().save(entity); return id; } public void update(T entity) { getSession().update(entity); } public int update(String hql,Object...field){ System.out.println(hql); for(Object obj : field){ System.out.println(obj); } Query query = getSession().createQuery(hql); if(field.length != 0){ for(int i=0 ;i < field.length; i++){ query.setParameter(i, field[i]); } } return query.executeUpdate(); } public Pagination getPagination(int pageNo, int pageSize) { Pagination pagination = new Pagination(pageNo, pageSize, getTotalCount()); List<T> list = getSession() .createQuery("from " + clazz.getSimpleName()).setFirstResult( pagination.getFirstResult()).setMaxResults( pagination.getPageSize()).list(); pagination.setList(list); return pagination; } protected Session getSession() { return sessionFactory.getCurrentSession(); } }