导出所选行为excle

要实现的是将所选行导出。例如勾选这两条

导出为

我的前台是easyUI实现的。所以前台代码为：

{
                                       { id:'btn_export',
                                        text : '导出所选行',
                                        iconCls : 'icon-print',
                                        handler : function() {
                                            var arr = $('#dayrec').datagrid(
                                                    'getSelections');
                                            if (arr.length <= 0) {
                                                $.messager.show({
                                                    title : '温馨提示!',
                                                    msg : '至少选择一行记录进行导出!'
                                                });
                                            } else {
                                                $.messager.confirm('温馨提示','确认导出?',function(r) {
                                                    if (r) {
                                                        var ids = '';
                                                        for (var i = 0; i < arr.length; i++) {
                                                            ids += arr[i].id+ ',';
                                                        }//从前台取得所选行的ids,拼接成字符串，传入后台
                                                        ids = ids.substring(0,ids.length - 1);
                                                        $('#downform').form('submit', {
                                                            url : "<%=basePath%>dayrec/exportSelected",//交给指定的url处理，后台可以接收到requestparam ids
                                                            method : "post",
                                                            onSubmit: function(param){
                                                                param.ids = ids;
                                                            },
                                                            error : function() {
                                                                $.messager.alert('温馨提示', '导出失败');
                                                            },                                                                                                                                                                                    
                                                            });
                                                        $('#dayrec').datagrid('unselectAll');
                                                    } else {
                                                        return;
                                                    }
                                                    
                                                });
                                            }
                                        }
                                    }

后台处理逻辑为：

@RequestMapping(value = "/exportSelected", method = RequestMethod.POST)
public @ResponseBody String exportSelectedUser(@RequestParam String ids,  HttpSession session, HttpServletResponse response) {
    List<Object[]> dataset = dayRecruitService.exportByid(ids); 
    String[] headers = new String[]{"日期","所属公司","招聘企业","面试人数","入职人数","入职率(%)","备注"};     
    if(dataset == null || dataset.size() < 1){
        return "没有查找到相应的数据,请刷新数据后重试";
    }
    response.setContentType("application/vnd.ms-excel");//;charset=utf-8
    response.setHeader("Content-Disposition", "attachment;filename=dayRecruit.xls");
    response.setHeader("Pragma","No-cache");
    response.setHeader ( "Cache-Control", "no-store"); 
    try {
        OutputStream sos = response.getOutputStream();

        ExportExcelsUtil.exportExcel(headers, dataset, sos);//如果不需要额外数据exportExcel(headers,dataset, sos)
      //  ExportExcelsUtil.exportExcel(2,1,2,"用户信息",headers,dataset, sos);//如果不需要额外数据exportExcel(headers,dataset, sos)
        response.flushBuffer();
    } catch (IOException e) {
        e.printStackTrace();
    }
    return "成功导出"+dataset.size()+"条用户数据。";
}

DayRecruitService的逻辑：

    public List<Object[]> exportByid(String ids) {
        
        List<Object[]> objList = new ArrayList<Object[]>();
        List<DayRecruit> dayrec_list=dayRecruitDAO.findById(ids);
        if(dayrec_list!=null&&dayrec_list.size()>0){
            for(int i=0;i<dayrec_list.size();i++){//循环遍历查询到的数据结果列表 将每一条数据插入到对应行单元格
                Object[] obj=new Object[7];
                DayRecruit rec=new DayRecruit();
                rec=dayrec_list.get(i);
                if(rec!=null){
                    obj[0]=rec.getDate();
                    obj[1]=rec.getCustomer().getOrganization().getOrganizationName();
                    obj[2]=rec.getCustomer().getEnterpriseName();
                    obj[3]=(rec.getViewerNu())==null?"":rec.getViewerNu();
                    obj[4]=(rec.getEntryNu()==null)?"":rec.getEntryNu();
                    if(rec.getViewerNu()!=null&&rec.getEntryNu()!=null)
                        obj[5]=(Math.round(Double.parseDouble(rec.getEntryNu())/Double.parseDouble(rec.getViewerNu())*100))/1.0+"%";
                    else
                        obj[5]="";
                    obj[6]=(rec.getRemarks()==null)?"":rec.getRemarks();
                    objList.add(obj);
                }
            }
        }
        return objList;//返回了对应的一行一行数据
    }

DayRecruitDAO后台逻辑为：

    public List<DayRecruit> findById(String ids) {
        // TODO Auto-generated method stub
        log.debug("get DayRecruit instance with id"+ids);
        try {
            List<DayRecruit> list = new ArrayList();
            List arrList = new ArrayList();
            if(ids == null || ids.trim().equals(""))
            {return list;}
            
            StringBuffer hql = new StringBuffer(
                    "from  DayRecruit  where id in(?");
            String[] id = ids.split(",");
            arrList.add(id[0]);
            for(int i=0;i<id.length;i++){
                hql.append(",?");
                arrList.add(id[i]);                
            }
            hql.append(")");
            list = (List<DayRecruit>) this.getListByHQL(-1, -1, hql.toString(),
                this.toStringArray(arrList));
            return list;

        } catch (RuntimeException re) {
            // TODO: handle exception
            log.debug("get failed",re);
            throw re;
        }                
    }

其中涉及到的hql语句模板是

    public List<?> getListByHQL(int nStartRow, int nRowSize, String strHQL, String... strParams){
        //log.debug("HQL：" + strHQL + "
 Params：" + ArrayUtils.toString(strParams));
        Query query=getSession().createQuery(strHQL);
        for (int j = 0,i=0; j < strParams.length; j++) {
            if(strParams[j]!=null) {
                if(!strParams[j].equals("")){
                   query.setString(i, strParams[j]);
                   i++;
                }
            }
        }
        if (nRowSize > 0 && nStartRow > -1) {
            query.setFirstResult((nStartRow-1)*nRowSize);
            query.setMaxResults(nRowSize);
        }

        //log.debug("BEGIN：" + DateUtils.getStrOfDateMinute());
        List<?> objList = query.list();
        //log.debug("END：" + DateUtils.getStrOfDateMinute());

        return objList;
    }
    

此处还涉及到了工具类  代码为：

import java.io.IOException;
import java.io.OutputStream;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import org.apache.commons.collections.map.ListOrderedMap;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFClientAnchor;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFPatriarch;
import org.apache.poi.hssf.usermodel.HSSFPicture;
import org.apache.poi.hssf.usermodel.HSSFRichTextString;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;

public class ExportExcelsUtil {
    /**
     * 
     * @param dataset 数据
     * @param out 流
     */
    public static <T> void exportExcel(Collection<T> dataset, OutputStream out) {
        exportExcel(0,0,0,"sheet1", null, dataset, out, "yyyy-MM-dd");
    }

    /**
     * 
     * @param headers 标题
     * @param dataset 数据
     * @param out
     */
    public static <T> void exportExcel(String[] headers, Collection<T> dataset,OutputStream out) {
        exportExcel(0,0,0,"sheet1", headers, dataset, out, "yyyy-MM-dd");
    }

    /**
     * 
     * @param headers 标题
     * @param dataset 数据
     * @param out 
     * @param pattern 日期格式
     */
    public static <T> void exportExcel(String[] headers, Collection<T> dataset,OutputStream out, String pattern) {
        exportExcel(0,0,0,"sheet1", headers, dataset, out, pattern);
    }
    
    /**
     * 导出数据
     * @param colSplit 需要冻结的列数目，如果没有传0
     * @param rowSplit 需要冻结的行数目，如果没有传0
     * @param dataBeginIndex 数据从第几个字段开始导出，每一条的记录，如果没有传0
     * @param sheetName 表格名字，sheet1的名称
     * @param headers 标题
     * @param dataset 数据
     * @param out 输出流
     */
    public static <T> void exportExcel(int colSplit,int rowSplit,int dataBeginIndex,String sheetName,String[] headers, Collection<T> dataset,OutputStream out){
        exportExcel(colSplit,rowSplit,dataBeginIndex,sheetName, headers, dataset, out, null);
    }

    /**
     * 这是一个通用的方法，利用了JAVA的反射机制，可以将放置在JAVA集合中并且符号一定条件的数据以EXCEL 的形式输出到指定IO设备上
     * @param <T>
     * 
     * @param title
     *            表格标题名
     * @param headers
     *            表格属性列名数组
     * @param dataset
     *            1.需要显示的数据集合,集合中一定要放置符合javabean风格的类的对象。此方法支持的 javabean属性的数据类型有基本数据类型及String,Date,byte[](图片数据)
     *            2.或者Map,key是string类型，value属性
     * @param out
     *            与输出设备关联的流对象，可以将EXCEL文档导出到本地文件或者网络中
     * @param pattern
     *            如果有时间数据，设定输出格式。默认为"yyy-MM-dd"，目前不需要
     */
    @SuppressWarnings("unchecked")
    public static <T> void exportExcel(int colSplit,int rowSplit,int dataBeginIndex,String title, String[] headers,Collection<T> dataset, OutputStream out, String pattern) {
        // 声明一个工作薄
        HSSFWorkbook workbook = new HSSFWorkbook();
        String sheetName = (title == null || title.equals("")) ? "sheet1" : title;
        // 生成一个表格
        HSSFSheet sheet = workbook.createSheet(sheetName);
        try{
            if(colSplit != 0 || rowSplit != 0){
                sheet.createFreezePane( colSplit, rowSplit, colSplit, rowSplit );//冻结首行(0,1,0,1)；2,1
            }
            // 设置表格默认列宽度为15个字节
            sheet.setDefaultColumnWidth((short) 15);
            // 生成一个样式
            HSSFCellStyle style = workbook.createCellStyle();
            // 设置这些样式
            style.setFillForegroundColor(HSSFColor.SKY_BLUE.index);
            style.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
            style.setBorderBottom(HSSFCellStyle.BORDER_THIN);
            style.setBorderLeft(HSSFCellStyle.BORDER_THIN);
            style.setBorderRight(HSSFCellStyle.BORDER_THIN);
            style.setBorderTop(HSSFCellStyle.BORDER_THIN);
            style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
            // 生成一个字体
            HSSFFont font = workbook.createFont();
            font.setColor(HSSFColor.VIOLET.index);
            font.setFontHeightInPoints((short) 12);
            font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
            // 把字体应用到当前的样式
            style.setFont(font);
            style.setWrapText(true);//设置自动换行
            
            // 生成并设置另一个样式
            HSSFCellStyle style2 = workbook.createCellStyle();
            style2.setFillForegroundColor(HSSFColor.LIGHT_YELLOW.index);
            style2.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
            style2.setBorderBottom(HSSFCellStyle.BORDER_THIN);
            style2.setBorderLeft(HSSFCellStyle.BORDER_THIN);
            style2.setBorderRight(HSSFCellStyle.BORDER_THIN);
            style2.setBorderTop(HSSFCellStyle.BORDER_THIN);
            style2.setAlignment(HSSFCellStyle.ALIGN_CENTER);
            style2.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
            // 生成另一个字体
            HSSFFont font2 = workbook.createFont();
            font2.setBoldweight(HSSFFont.BOLDWEIGHT_NORMAL);
            // 把字体应用到当前的样式
            style2.setFont(font2);
            style2.setWrapText(true);//设置自动换行

            // 声明一个画图的顶级管理器
            HSSFPatriarch patriarch = sheet.createDrawingPatriarch();
            // 定义注释的大小和位置,详见文档  
            //HSSFComment comment = patriarch.createComment(new HSSFClientAnchor(0, 0, 0, 0, (short) 4, 2, (short) 6, 5));
            // 设置注释内容  
            //comment.setString(new HSSFRichTextString("可以在POI中添加注释！"));
            // 设置注释作者，当鼠标移动到单元格上是可以在状态栏中看到该内容. 
            //comment.setAuthor("leno");

            // 产生表格标题行
            HSSFRow row = sheet.createRow(0);
            for (short i = 0; i < headers.length; i++) {
                HSSFCell cell = row.createCell(i);
                cell.setCellStyle(style);
                HSSFRichTextString text = new HSSFRichTextString(headers[i]);
                cell.setCellValue(text);
            }

            // 遍历集合数据，产生数据行
            Iterator<T> it = dataset.iterator();
            int index = 0;
            while (it.hasNext()) {
                index++;
                row = sheet.createRow(index);
                T t = (T) it.next();
                if(t instanceof Class){
                    // 利用反射，根据javabean属性的先后顺序，动态调用getXxx()方法得到属性值
                    Field[] fields = t.getClass().getDeclaredFields();
                    for (short i = 0; i < fields.length; i++) {
                        HSSFCell cell = row.createCell(i);
                        cell.setCellStyle(style2);
                        Field field = fields[i];
                        String fieldName = field.getName();
                        String getMethodName = "get" + fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1);
                        Class tCls = t.getClass();
                        Method getMethod = tCls.getMethod(getMethodName, new Class[] {});
                        Object value = getMethod.invoke(t, new Object[] {});
                        // 判断值的类型后进行强制类型转换
                        String textValue = null;
                        if (value instanceof byte[]) {
                            // 有图片时，设置行高为60px;
                            row.setHeightInPoints(600);
                            // 设置图片所在列宽度为80px,注意这里单位的一个换算
                            sheet.setColumnWidth(i, (short) (35.7 * 400));
                            // sheet.autoSizeColumn(i);
                            byte[] bsValue = (byte[]) value;
                            HSSFClientAnchor anchor = new HSSFClientAnchor(0, 0, 1023, 600, i, index, (short) (i+1), index+1);
                            anchor.setAnchorType(2);
                            HSSFPicture pic = patriarch.createPicture(anchor, workbook.addPicture(bsValue, HSSFWorkbook.PICTURE_TYPE_JPEG));
                            pic.resize();//这句话一定不要，这是用图片原始大小来显示
                        } else {
                            // 其它数据类型都当作字符串简单处理
                            textValue = value.toString();
                        }
                        
                        if (textValue != null){
                            HSSFRichTextString richString = new HSSFRichTextString(textValue);
                             HSSFFont font3 = workbook.createFont();
                             font3.setColor(HSSFColor.BLUE.index);
                             richString.applyFont(font3);
                             cell.setCellValue(richString);
                        }
                    }
                }else if(t instanceof ListOrderedMap || t instanceof HashMap){
                    //HashMap<String,String> map = null;
                    ListOrderedMap map = (ListOrderedMap) t;
                    Iterator<String> keys = map.keySet().iterator();
                    short i = 0;
                    while(keys.hasNext()){
                        HSSFCell cell = row.createCell(i);
                        cell.setCellStyle(style2);
                        String keyname = keys.next();
                        //此处根据keyname生成标题
                        Object keyValue = map.get(keyname);
                        String textValue = null;
                        if(keyValue instanceof byte[]){
                            // 有图片时，设置行高为60px;
                            row.setHeightInPoints(300);
                            // 设置图片所在列宽度为80px,注意这里单位的一个换算
                            sheet.setColumnWidth(i, (short) (35.7 * 200));
                            // sheet.autoSizeColumn(i);
                            byte[] bsValue = (byte[]) keyValue;
                            HSSFClientAnchor anchor = new HSSFClientAnchor(0, 0, 1023, 255, i, index, (short) (i+1), index+1);
                            anchor.setAnchorType(2);
                            HSSFPicture pic = patriarch.createPicture(anchor, workbook.addPicture(bsValue, HSSFWorkbook.PICTURE_TYPE_JPEG));
                            //pic.resize();//这句话一定不要，这是用图片原始大小来显示
                        }else{
                            textValue = keyValue.toString();
                        }
                        if (textValue != null){
                                HSSFRichTextString richString = new HSSFRichTextString(textValue);
                            HSSFFont font3 = workbook.createFont();
                            font3.setColor(HSSFColor.BLUE.index);
                            richString.applyFont(font3);
                            cell.setCellValue(richString);
                            }
                        i++;
                    }//end while(keys.hasNext())
                }else if(t instanceof Object[]){
                    Object[] object = (Object[])t;
                    //忽略前两个id字段，之后可以作为参数传入
                    for(int len = dataBeginIndex;len<object.length;len++){                        
                        String textValue = "";
                        if(object[len] != null){
                            textValue = object[len].toString();
                        }
                        HSSFCell cell = row.createCell(len-dataBeginIndex);
                        cell.setCellStyle(style2);
                        HSSFRichTextString richString = new HSSFRichTextString(textValue);
                        HSSFFont font3 = workbook.createFont();
                        font3.setColor(HSSFColor.BLUE.index);
                        richString.applyFont(font3);
                        cell.setCellValue(richString);
                    }
                }
                
            }
            workbook.write(out);
            out.flush();
            out.close();
        }catch (SecurityException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (NoSuchMethodException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IllegalArgumentException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } finally {
            // 清理资源
            
        }

    }

}