solrj 实现 group查询

public List SearchByGroup(String sServer, String sQuery, String sSortFld, boolean bAsc,
     String sPage, String sRows, String sFields, String sShards)
    {
 List _resultList = new ArrayList(); //返回结果列表，每个结果存放到一个hashmap中
 String[] _arrsFields = sFields.split(","); //字段列表
 int iSeriesNum = 0; //页面显示的自然增长序号
 this.pageSize = Integer.parseInt(sRows);
 String sStart = (Integer.parseInt(sPage) - 1) * Integer.parseInt(sRows) + "";
 SolrQuery _query = new SolrQuery();
 _query.setQuery(sQuery);
 _query.setParam("start", sStart);
 _query.setParam("rows", sRows);
 _query.setParam("group", true);
 _query.setParam("group.field", "FID"); //按照FID同族专利去重
 _query.setParam("group.ngroups", true);
 if (sSortFld != null && !"".equalsIgnoreCase(sSortFld))
 {
     if (bAsc)
     {
  _query.setSortField(sSortFld, SolrQuery.ORDER.asc);
     }
     else
     {
  _query.setSortField(sSortFld, SolrQuery.ORDER.desc);
     }
 }
 if (sShards != null)
 {
     // _query.setParam("shards", sShards);
 }
 if (sFields != null)
 {
     _query.setParam("fl", sFields);
 }
 CommonsHttpSolrServer commonsHttpSolrServer = null;
 
 try
 {
     commonsHttpSolrServer = new CommonsHttpSolrServer(sServer);
     commonsHttpSolrServer.setRequestWriter(new BinaryRequestWriter());
     QueryResponse _solrRes = commonsHttpSolrServer.query(_query);
     GroupResponse _solrGroupRes = _solrRes.getGroupResponse();
     List<GroupCommand> _listGroup = _solrGroupRes.getValues();
     if (_listGroup == null || _listGroup.size() == 0) //检索到group为null 或者size 为0
     {
  this.lTotal = 0;
     }
     else
     {
  System.out.println(_listGroup.size());
  Integer _iSize = _listGroup.get(0).getNGroups();
  this.lTotal = _iSize.intValue();
  System.out.println("hits:" + _iSize.intValue());
  List<Group> _groups = _listGroup.get(0).getValues();
  //System.out.println("group size:" + _groups.size());
  for(int i=0;i<_groups.size();i++) //对返回的每个组进行循环，组的size为Page分页大小
  {
      Group _g = _groups.get(i);
      SolrDocumentList _solrResult = null;
      _solrResult = _g.getResult();
    
    //  System.out.println("group include hit:" + _solrResult.size());
     
      for(int j=0;j<_solrResult.size();j++) //对每个组内的记录进行循环，默认组内记录数为1，可由group.limit参考控制
      {
   Map _map = new HashMap(); //存放记录
   SolrDocument _doc = _solrResult.get(j);
   iSeriesNum = iSeriesNum + 1 ; //页面显示的自然增长序号
   _map.put("num", new Integer(iSeriesNum + new Integer(sStart).intValue()).toString());
   for(int k=0;k<_arrsFields.length;k++) //对记录的每个字段循环
   {
       String sValue = _doc.getFieldValue(_arrsFields[k]).toString();
       if (sValue != null)
       {
    _map.put(_arrsFields[k], sValue);
       }
       else
       {
    continue;
       }
   }
   _resultList.add(_map);
      }
      _solrResult = null;
  }
     }

 }
 catch (IOException e)
 {
     e.printStackTrace();
 }
 catch (SolrServerException e)
 {
     e.printStackTrace();
 }
 return _resultList;
    }