Java sdk/java poi hssf code to creat excel with folder structure,( i,e folders, subfolders and childrens )

I need to create a folder structure in the excel file .

To be precise, am working on Java sdk of business objecsts . i need some help in getting folder structure using this java .

Folder strcuture should look like following way in excel .

A(parent )
|
|
|_topfolder1__
|             |__subfolder1__
|                           |__childrens
|_topfolder2__
              |__subfolder2__
                             |__sufolder2a__
                                            |__childrens

And right now i have the following code, where am getting output in RAD console, but i need to display in excel such a way of folder hierarchy

Note : here all HSSF lines are half done, pls bear with that !!

    if(topFolders.size() < 1)</br>  
    {  
    System.out.println("no top level folders");  
    }  
    else  
    {  
    HSSFFont font = wb.createFont();  
    font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);  
    HSSFCellStyle style = wb.createCellStyle();  
    style.setAlignment(HSSFCellStyle.ALIGN_CENTER);  
    style.setFont(font);  
    HSSFCell cell;  
    HSSFRow row1 = sheet.createRow(1);  
    sheet.createFreezePane(1,1,1,1);  
    for( i=0; i<topFolders.size(); i++)  
    {  
    IInfoObject topFolder = (IInfoObject) topFolders.get(i);  
    System.out.println("Top level folders"+topFolder.getTitle());  
    row3=sheet.createRow(i);  
    row3.createCell(0).setCellValue(topFolder.getTitle());  
    if(topFolder.getKind()!="FOLDER")  
    {   
    childcount=getchilds(boInfoStore,topFolder.getID() );  
    System.out.println("no.of childs"+childcount);  
    }  
    count++;  
    int subfoldercount=GetSubFolders(boInfoStore, topFolder.getID());  
    System.out.println("no.of.subfolders"+subfoldercount);  
    }  
    System.out.println("total no .of topfolder"+count);  
    }  
    FileOutputStream fileOut = new FileOutputStream("c://");  
    wb.write(fileOut);  
    fileOut.close();    
    } catch(Exception e)  
    {  
     System.out.println("--------------"+e.getMessage());  
    }  
    }  

    static int GetSubFolders(IInfoStore oInfoStore, int folderID)    
    {  
    String query = "select * from ci_infoobjects where si_kind='folder' and +folderid      
    IInfoObjects folders = oInfoStore.query(query);
    if(folders.size() < 1)
    return 0;
    else
    {
    for(int i=0; i<folders.size(); i++)
    {
    IInfoObject SubFolder = (IInfoObject)folders.get(i);
    System.out.println("_subfolders"+SubFolder.getTitle());
    //HSSFRow row4=sheet.createRow(i+1);
    //row4.createCell(1).setCellValue(SubFolder.getTitle());
    if(SubFolder.getKind()!="Folder")
    {
    int num=getchilds(oInfoStore,SubFolder.getID() );
     System.out.println("childrens"+num);
                }
           int subfolder2=GetSubFolders(oInfoStore,((IInfoObject)folders.get(i)).getID());
              System.out.println("Number of SUBFOLDERS"+subfolder2);
                  }
           return folders.size();
   }
   }

   static int getchilds(IInfoStore ooInfoStore,int childid ) 
   {
   String query3="select * from ci_infoobjects where si_parentid="+ childid;
   IInfoObjects childrens = ooInfoStore.query(query3);
   if(childrens.size() < 1)
      {
   return 0;
   }
   else
   {
    //int m=1;
    for(int l=0; l<childrens.size(); l++)
   {
    IInfoObject childs = (IInfoObject)childrens.get(l);
     System.out.println("childreports"+childs.getTitle());
     HSSFRow rowchild=sheet.createRow(l+1);
     rowchild.createCell(1).setCellValue(childs.getTitle());
      }
   }
   return childrens.size();
   } 
   }