Hibernate的BaseDao辅助类

1、BaseDao接口类,该类封装了一些hibernate操作数据库的一些常用的方法，包括分页查询，使用该类极大的简化了hibernate的开发

BaseDao.java

 package com.kjonline2.dao;

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

 public interface BaseDao<T> {

     /**
      * 保存一个对象
      *
      * @param o
      * @return
      */
     public Serializable save(T o);  

     /**
      * 删除一个对象
      *
      * @param o
      */
     public void delete(T o);  

     /**
      * 更新一个对象
      *
      * @param o
      */
     public void update(T o);  

     /**
      * 保存或更新对象
      *
      * @param o
      */
     public void saveOrUpdate(T o);  

     /**
      * 查询
      *
      * @param hql
      * @return
      */
     public List<T> find(String hql); 

     /**
      * 查询部分
      * @param hql
      * @param num
      * @return
      */
     public List<T> findPart(String hql,int num);  

     /**
      * 查询集合
      *
      * @param hql
      * @param param
      * @return
      */
     public List<T> find(String hql, Object[] param);  

     /**
      * 查询集合
      *
      * @param hql
      * @param param
      * @return
      */
     public List<T> find(String hql, List<Object> param);  

     /**
      * 查询集合(带分页)
      *
      * @param hql
      * @param param
      * @param page
      *            查询第几页
      * @param rows
      *            每页显示几条记录
      * @return
      */
     public List<T> find(String hql, Object[] param, Integer page, Integer rows);  

     /**
      * 查询集合(带分页)
      *
      * @param hql
      * @param param
      * @param page
      * @param rows
      * @return
      */
     public List<T> find(String hql, List<Object> param, Integer page, Integer rows);  

     /**
      * 获得一个对象
      *
      * @param c
      *            对象类型
      * @param id
      * @return Object
      */
     public T get(Class<T> c, Serializable id);  

     /**
      * 获得一个对象
      *
      * @param hql
      * @param param
      * @return Object
      */
     public T get(String hql, Object[] param);  

     /**
      * 获得一个对象
      *
      * @param hql
      * @param param
      * @return
      */
     public T get(String hql, List<Object> param);  

     /**
      * select count(*) from 类
      *
      * @param hql
      * @return
      */ 

     public Long count(String hql);
     /**
      * select count(*) from 类
      * @param hql
      * @return
      */
     public Integer getCount(String hql);  

     /**
      * select count(*) from 类
      *
      * @param hql
      * @param param
      * @return
      */
     public Long count(String hql, Object[] param);  

     /**
      * select count(*) from 类
      *
      * @param hql
      * @param param
      * @return
      */
     public Long count(String hql, List<Object> param);  

     /**
      * 执行HQL语句
      *
      * @param hql
      * @return 响应数目
      */
     public Integer executeHql(String hql);  

     /**
      * 执行HQL语句
      *
      * @param hql
      * @param param
      * @return 响应数目
      */
     public Integer executeHql(String hql, Object[] param);  

     /**
      * 执行HQL语句
      *
      * @param hql
      * @param param
      * @return
      */
     public Integer executeHql(String hql, List<Object> param);  

 }

该类使用泛型来做接口，使该类拥有极好的通用性和扩展性，可供多个不同类型的service来调用

2、BaseDao的实现类，BaseDaoImpl.java，实现了BaseDao接口的java类，可供service的实现类来调用，使用spring的@Autowired注解来调用则更为方便

 package com.kjonline2.dao;

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

 import org.hibernate.Query;
 import org.hibernate.Session;
 import org.hibernate.SessionFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Repository;
 import org.springframework.transaction.annotation.Transactional;

 @Repository("baseDao")
 @SuppressWarnings("all")
 @Transactional
 public class BaseDaoImpl<T> implements BaseDao<T> {

         private SessionFactory sessionFactory;

         public SessionFactory getSessionFactory() {
             return sessionFactory;
         }

         @Autowired
         public void setSessionFactory(SessionFactory sessionFactory) {
             this.sessionFactory = sessionFactory;
         }

         private Session getCurrentSession() {
             return sessionFactory.getCurrentSession();
         }

         public Serializable save(T o) {
             return this.getCurrentSession().save(o);
         }

         public void delete(T o) {
             this.getCurrentSession().delete(o);
         }

         public void update(T o) {
             this.getCurrentSession().update(o);
         }

         public void saveOrUpdate(T o) {
             this.getCurrentSession().saveOrUpdate(o);
         }

         public List<T> find(String hql) {
             return this.getCurrentSession().createQuery(hql).list();
         }

         public List<T> find(String hql, Object[] param) {
             Query q = this.getCurrentSession().createQuery(hql);
             if (param != null && param.length > 0) {
                 for (int i = 0; i < param.length; i++) {
                     q.setParameter(i, param[i]);
                 }
             }
             return q.list();
         }

         public List<T> find(String hql, List<Object> param) {
             Query q = this.getCurrentSession().createQuery(hql);
             if (param != null && param.size() > 0) {
                 for (int i = 0; i < param.size(); i++) {
                     q.setParameter(i, param.get(i));
                 }
             }
             return q.list();
         }

         public List<T> find(String hql, Object[] param, Integer page, Integer rows) {
             if (page == null || page < 1) {
                 page = 1;
             }
             if (rows == null || rows < 1) {
                 rows = 10;
             }
             Query q = this.getCurrentSession().createQuery(hql);
             if (param != null && param.length > 0) {
                 for (int i = 0; i < param.length; i++) {
                     q.setParameter(i, param[i]);
                 }
             }
             return q.setFirstResult((page - 1) * rows).setMaxResults(rows).list();
         }

         public List<T> find(String hql, List<Object> param, Integer page, Integer rows) {
             if (page == null || page < 1) {
                 page = 1;
             }
             if (rows == null || rows < 1) {
                 rows = 10;
             }
             Query q = this.getCurrentSession().createQuery(hql);
             if (param != null && param.size() > 0) {
                 for (int i = 0; i < param.size(); i++) {
                     q.setParameter(i, param.get(i));
                 }
             }
             return q.setFirstResult((page - 1) * rows).setMaxResults(rows).list();
         }

         public T get(Class<T> c, Serializable id) {
             return (T) this.getCurrentSession().get(c, id);
         }

         public T get(String hql, Object[] param) {
             List<T> l = this.find(hql, param);
             if (l != null && l.size() > 0) {
                 return l.get(0);
             } else {
                 return null;
             }
         }

         public T get(String hql, List<Object> param) {
             List<T> l = this.find(hql, param);
             if (l != null && l.size() > 0) {
                 return l.get(0);
             } else {
                 return null;
             }
         }

         public Long count(String hql) {
             return (Long) this.getCurrentSession().createQuery(hql).uniqueResult();
         }

         public Long count(String hql, Object[] param) {
             Query q = this.getCurrentSession().createQuery(hql);
             if (param != null && param.length > 0) {
                 for (int i = 0; i < param.length; i++) {
                     q.setParameter(i, param[i]);
                 }
             }
             return (Long) q.uniqueResult();
         }

         public Long count(String hql, List<Object> param) {
             Query q = this.getCurrentSession().createQuery(hql);
             if (param != null && param.size() > 0) {
                 for (int i = 0; i < param.size(); i++) {
                     q.setParameter(i, param.get(i));
                 }
             }
             return (Long) q.uniqueResult();
         }

         public Integer executeHql(String hql) {
             return this.getCurrentSession().createQuery(hql).executeUpdate();
         }

         public Integer executeHql(String hql, Object[] param) {
             Query q = this.getCurrentSession().createQuery(hql);
             if (param != null && param.length > 0) {
                 for (int i = 0; i < param.length; i++) {
                     q.setParameter(i, param[i]);
                 }
             }
             return q.executeUpdate();
         }

         public Integer executeHql(String hql, List<Object> param) {
             Query q = this.getCurrentSession().createQuery(hql);
             if (param != null && param.size() > 0) {
                 for (int i = 0; i < param.size(); i++) {
                     q.setParameter(i, param.get(i));
                 }
             }
             return q.executeUpdate();
         }

         public List<T> findPart(String hql, int num) {
             // TODO Auto-generated method stub
             Query q = this.getCurrentSession().createQuery(hql);
             q.setMaxResults(num);
             return q.list();
         }

         public Integer getCount(String hql) {
             // TODO Auto-generated method stub
             return ((Number) this.getCurrentSession().createQuery(hql).uniqueResult()).intValue();
         }

     }