Hibernate实现增删改查

package com.atlas.DAOFactory.role;

import java.util.List;

import org.apache.log4j.Logger;
import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import com.atlas.hibernate.HibernateSessionFactory;
import com.atlas.util.Logs;

public class RoleDAO {

Session session;
List list=null;
Transaction tx;
Query query;
Logger logger=Logs.logs(this.getClass());

/*
* 插入一个role角色对象，根据结果返回true或 false
*/
public boolean insertRole(Role role) {
session = HibernateSessionFactory.getSession();
tx = session.beginTransaction();//创建事务
boolean flag=false;
try {
session.save(role);
tx.commit();//事务提交
flag=true;
} catch (HibernateException e) {
Logs.writeError(logger,"添加角色失败");
// TODO: handle exception
}finally{
try {
session.close();
} catch (HibernateException e) {
// TODO: handle exception
Logs.writeWarn(logger, "关闭session失败");
}
}
return flag;
}

/*
* 跟据action传递得记录id，删除一条记录信息
*/
public void deleteRole(Long id){
try {
session=HibernateSessionFactory.getSession();
tx=session.beginTransaction();
Role role=new Role();
role.setId(id);
session.delete(role);
tx.commit();
} catch (HibernateException e) {
// TODO: handle exception
e.printStackTrace();
Logs.writeError(logger, "删除角色失败");

}finally{
try {
session.close();
} catch (Exception e) {
// TODO: handle exception
Logs.writeWarn(logger, "session关闭失败");
}
}
}
/*
* 根据updateRole.jsp传入得id执行更新操作
*/
public boolean updateRole(Role role){
session=HibernateSessionFactory.getSession();
tx=session.beginTransaction();
boolean flag=false;
try {

session.update(role);
tx.commit();
flag=true;
} catch (HibernateException e) {
// TODO: handle exception
e.printStackTrace();
}finally{
try {
session.close();
} catch (Exception e) {
// TODO: handle exception
e.printStackTrace();
}
}
return flag;
}

/*
* 从数据库中查询出所有的角色，并返回结果集list
*/
public List selectRole(){
session=HibernateSessionFactory.getSession();
tx=session.beginTransaction();
List list=null;
try {
String hql="from Role";
query=session.createQuery(hql);
list=query.list();

} catch (HibernateException e) {
// TODO: handle exception
Logs.writeError(logger, "查询出所有角色失败");
}finally{
try {
session.close();
} catch (HibernateException e) {
Logs.writeWarn(logger, "session关闭失败");
// TODO: handle exception
}
}
return list;
}
/*
* 根据modifyOrgan.jsp传入得id,查询出一条信息
*/
public List findby(Long id){

session=HibernateSessionFactory.getSession();
tx=session.beginTransaction();
try {
String hql="from Role where id="+id;
query=session.createQuery(hql);
list=query.list();
} catch (HibernateException e) {
// TODO: handle exception
e.printStackTrace();
}finally{
try {
session.close();
} catch (Exception e) {
// TODO: handle exception
e.printStackTrace();
}
}

return list;
}