hibernate BASEDAO

package com.dj.baseDao; import java.util.Collection; import java.util.List; import org.hibernate.Session; import java.util.Iterator; import org.hibernate.Query; import org.hibernate.SQLQuery; import org.hibernate.SessionFactory; import org.hibernate.Transaction; import com.hibernate.factory.HibernateSessionFactory; public class BaseDAO { private SessionFactory sessionFactory; /** * 功能：获得数据库连接的Session * @return Session */ public Session getSession() { return HibernateSessionFactory.14:20 2008-9-1 } /** * 功能：关闭session * @param session */ protected void closeSession(Session session) { if (session != null && session.isOpen()) { session.close(); session = null; } } /** * 功能：添加新的记录 * @param entity 映射类 * @return true 添加记录成功 * false 添加记录失败 */ public boolean add(Object entity) { Session session = null; Transaction tr = null; boolean commitflag = false; try { session = this.getSession(); tr = session.beginTransaction(); session.save(entity); tr.commit(); commitflag = true; session.flush(); session.clear(); } catch (Exception e) { e.printStackTrace(); return false; } finally { if (!commitflag) { try { if (tr != null) tr.rollback(); } catch (Exception e1) { e1.printStackTrace(); } } this.closeSession(session); } return true; } /** * 功能:删除记录 * @param entity 映射类 * @return true 删除成功 * false删除失败 */ public boolean delete(Object entity) { Session session = null; Transaction tr = null; boolean commitflag = false; try { session = this.getSession(); tr = session.getTransaction(); tr.begin(); session.delete(entity); tr.commit(); commitflag = true; session.flush(); session.clear(); } catch (Exception e) { if (tr != null) tr.rollback(); System.out.println(" Class=" + entity.getClass().getName()+e); return false; } finally { if (!commitflag) { try { if (tr != null) tr.rollback(); } catch (Exception e) { e.printStackTrace(); } } this.closeSession(session); } return true; } /** * 通过LONG类型ID 删除一条数据库记录 * @param clazz 映射类.class * @param id PK 值 * @return true 删除成功 * false 删除失败 */ public boolean delete(Class clazz, long id) { try { Object entity = this.getByPk(clazz, id); if (entity != null) { this.delete(entity); } else { System.out.println(clazz.getName() + " 的关键字为 " + id+ " 的对象不存在 "); return false; } } catch (Exception e) { e.printStackTrace(); return false; } return true; } /** * 通过int类型ID 删除一条数据库记录 * @param clazz 映射类.class * @param id PK 值 * @return true 删除成功 * false 删除失败 */ public boolean delete(Class clazz, int id) { try { Object entity = this.getByPk(clazz, id); if (entity != null) { this.delete(entity); } else { System.out.println(clazz.getName() + " 的关键字为 " + id+ " 的对象不存在 "); return false; } } catch (Exception e) { e.printStackTrace(); return false; } return true; } /** * 通过String类型ID 删除一条数据库记录 * @param clazz 映射类.class * @param id PK 值 * @return true 删除成功 * false 删除失败 */ public boolean delete(Class clazz, String id) { try { Object entity = this.getByPk(clazz, id); if (entity != null) { this.delete(entity); } else { System.out.println(clazz.getName() + " 的关键字为 " + id+ " 的对象不存在 "); return false; } } catch (Exception e) { e.printStackTrace(); return false; } return true; } /** * 删除某个表的所有数据 * @param clazz 实体类.class * @return true 删除成功 * false 删除失败 */ public boolean deleteTableData(Class entity) { Session session = null; Transaction tr = null; boolean commitflag = false; try { session = this.getSession(); tr = session.beginTransaction(); Query query = session.createQuery(" delete from " + entity.getName()); query.executeUpdate(); tr.commit(); commitflag = true; session.flush(); } catch (Exception e) { System.out.println("从数据库中删除" + entity.getName() + "的所有实例失败！"+ e); return false; } finally { if (!commitflag) { try { if (tr != null) tr.rollback(); } catch (Exception e) { e.printStackTrace(); } } this.closeSession(session); } return true; } /** * 通过实体类集合 删除集合中的所有数据 * @param entities 实体类的集合(list vector Set等) * @return true 删除成功 false 删除失败 */ public boolean deleteByEntities(Collection entities) { Session session = null; Transaction tr = null; boolean commitflag = false; try { session = this.getSession(); tr = session.beginTransaction(); Iterator ite = entities.iterator(); while (ite.hasNext()) { session.delete(ite.next()); } tr.commit(); commitflag = true; session.flush(); } catch (Exception e) { e.printStackTrace(); return false; } finally { if (!commitflag) { try { if (tr != null) tr.rollback(); } catch (Exception e) { e.printStackTrace(); } } this.closeSession(session); } return true; } /** * 通过HQL查询数据 * @param strhql * @return list */ public List find(String strhql) { List result = null; System.out.println("find(String) queryString=" + strhql); Session session = null; try { session = this.getSession(); Query query = session.createQuery(strhql); result = query.list(); } catch (Exception e) { System.out.println("执行数据库中查询时失败,语句为：" + strhql+ e); } finally { this.closeSession(session); } return result; } /** * 通过SQL查询数据 * @param strsql sql * @return list */ public List findBySql(String strsql) { Session session = null; List result = null; try { session = this.getSession(); SQLQuery query = session.createSQLQuery(strsql); result = query.list(); } catch (Exception e) { e.printStackTrace(); } finally { this.closeSession(session); } return result; } /** * 功能：通过PK获取数据 * @param 实体类.class * @param id PK * @return entity */ public Object getByPk(Class clazz, int id) { Object result = null; Session session = null; try { session = this.getSession(); result = session.get(clazz, new Integer(id)); } catch (Exception e) { e.printStackTrace(); } finally { this.closeSession(session); } return result; } /** * 功能：通过PK获取数据 * @param 实体类.class * @param id PK * @return entity */ public Object getByPk(Class clazz, long id) { System.out.println("getByPk(Class, Long) Class=" + clazz.getName()+ ",id=" + id); Object result = null; Session session = null; try { session = this.getSession(); result = session.get(clazz, new Long(id)); } catch (Exception e) { e.printStackTrace(); } finally { this.closeSession(session); } return result; } /** * 功能：通过PK获取数据 * @param 实体类.class * @param id PK * @return entity */ public Object getByPk(Class clazz, String id) { System.out.println("getByPk(Class, String) Class=" + clazz.getName() + ",id=" + id); Object result = null; Session session = null; try { session = this.getSession(); result = session.get(clazz, id); } catch (Exception e) { e.printStackTrace(); } finally { this.closeSession(session); } return result; }