java应用中两个问题解决方法.doc

一、多表查询分页方法一：public List getUserlist(String userAccount,String EmployeeFullName, int startNum,int pagelength) int totalResults; /总记录的条数 String condition=; if(!userAccount.equals()&!EmployeeFullName.equals() condition= and sysuser.susUseraccount like%+userAccount+% or employee.coeFullname like%+EmployeeFullName+%; else if(!EmployeeFullName.equals()&userAccount.equals() condition= and employee.coeFullname like%+EmployeeFullName+%; else if(!userAccount.equals()&EmployeeFullName.equals() condition= and sysuser.susUseraccount like%+userAccount+%; String hql =select employee.coeEmployeeid,employee.coeFullname,employee.coeSexuality,employee.coePictureurl,sysuser.susAccountid, sysuser.susUseraccount, sysuser.susForumUsersLevel from SmcSystemuser sysuser,HrmEmployee employee where sysuser.susEmployeeid=employee.coeEmployeeid +condition+ order by sysuser.susAccountid; System.out.println(hql:+hql); List res = new Vector();/ 将用于存放保存的结果集合 Session session = null; ScrollableResults srs = null; try /得到一个Hibernate Session /分页关键语句 session = this.getSessionFactory().openSession(); /下面创建一个匿名Query实例并调用它的scroll()方法返回以 /ScrollableResults形式组织的查询结果 Query query = session.createQuery(hql); query.setFirstResult(startNum); query.setMaxResults(pagelength); srs = query.scroll(); / 将查询结果放入List保存 int i=0; while(srs.next() i+; res.add(new EmpUsrAccountBean(srs.getString(0), srs.getString(1), srs.getString(2), srs.getString(3), srs.getString(4), srs.getString(5), srs.getString(6); catch(HibernateException he) if(srs!=null) try srs.close(); catch(Exception e) System.out.println(e.getMessage(); System.out.println(he.getMessage(); finally try session.close(); catch(Exception e) System.out.println(e.getMessage(); return res; 错误：在执行到srs = query.scroll(); 报如下错误ERROR AssertionFailure an assertion failure occured (this may indicate a bug in Hibernate, but is more likely due to unsafe use of the session)org.hibernate.AssertionFailure: scrollable result sets are not enabledat org.hibernate.jdbc.AbstractBatcher.getPreparedStatement(AbstractBatcher.java:413)原因分析：jboss里没有连结数据库的驱动解决办法：在jboss目录下的serverdefaultlib中加入数据库驱动方法二：将获取的值存入一个新的list对象中，在页面中list（list数组）取值public List getEmplistByName(String empName,int offset,int length) List emplist=new ArrayList();String hql=;try if(empName.equals()hql=select new list(emp,org) from HrmEmployee emp,HrmOrganizations org where emp.coeBelongdepid=org.cooOrganizationid order by emp.coeEmployeeid;else hql=select new list(emp,org) from HrmEmployee emp,HrmOrganizations org where emp.coeBelongdepid=org.cooOrganizationid and emp.coeFullname like%+empName+% order by emp.coeEmployeeid;return getListForPage(hql, offset,length) ; catch (DataAccessException e) e.printStackTrace();return emplist;页面中取值为$emplist0.coeFullname二、配