巴巴运动网学习笔记(21-25)

public <T> ScrollResult<T> getScrollResult(Class<T> classType,int begin, int max,LinkedHashMap<String, String> orderHashMap,String filterString,Object[] params) {
ScrollResult<T> scrollResult = new ScrollResult<T>();
String entityName = getEntiyName(classType);
String orderString = getOrderString(orderHashMap);
Query query = entityManager.createQuery("select p from "+entityName+" p "+(filterString==null?"":"where "+filterString+" ")+orderString);
for(int i=0;params!=null&&filterString!=null&&!filterString.equals("")&&i<params.length;i++){
query.setParameter(i+1, params[i]);
}
if(begin!=-1&&max!=-1){
query.setFirstResult(begin).setMaxResults(max);
}
scrollResult.setResultList(query.getResultList());
query = entityManager.createQuery("select count(p) from "+entityName+" p "+(filterString==null?"":"where "+filterString));
for(int i=0;params!=null&&filterString!=null&&!filterString.equals("")&&i<params.length;i++){
query.setParameter(i+1, params[i]);
}
scrollResult.setCount((Long)query.getSingleResult());
return scrollResult;
}