//需要保证Emp和EmpProperties中的setter和getter以及属性以及 参数占位符(:eName) 的一致
//动态查询

    @Test

    public void test4(){

        EmpProperties ep=new EmpProperties();

        //set query conditions

        ep.seteName("%A%");

        ep.setStartDate(new Date(383155200000L));

        ep.setEndDate(new Date());

        ep.setJob("CLERK");

        //1.obtain org.hibernate.Session object.

        Session ss=HibernateUtil.getSession();

        //2.hql statement: s

        StringBuffer hql=new StringBuffer("from Emp e where 1=1 ");

        //3.判断EmpProperties总属性是否为null

        if(ep.geteName()!=null){

            hql.append(" and e.eName like :eName ");//e.eName和Emp中的属性保持一致|:eName和EmpProperties中的属性保持一致

        }

        if(ep.getStartDate()!=null){

            hql.append(" and e.hireDate>=:startDate  ");

        }

        if(ep.getEndDate()!=null){

            hql.append(" and e.hireDate<=:endDate ");

        }

        if(ep.getJob()!=null){

            hql.append(" and e.job=:job");

        }

        //执行hql语句,hql转换为String(使用toString()方法)

        Query qr=ss.createQuery(hql.toString());

        //给hql语句中的参数赋值

        qr.setProperties(ep);

        @SuppressWarnings("unchecked")

        List<Emp> el= qr.list();

        for (Emp emp : el) {

            System.out.println(emp.geteName()+"\t"+ emp.getEmpNo());

        }

        System.out.println("查询记录数: "+el.size());

        HibernateUtil.closeResource(ss);

    }