JAVA導出EXCEL表格

工作時遇到了一個excel 導出的問題 , 原本是想直接用前端的table直接做excel 導出,但是又發現有點不滿足需求

是 同是將三個小表格放入到一個excel表格中去,於是就上網找資料

這篇貼子就寫的比較清楚詳細 於是快樂的抄襲就開始了,但是發現一些不足之處,於是就稍微改動了一下,覺得還是滿足使用的

#貼上代碼

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;


import java.io.*;
import java.util.*;

public class ExcelUtil {

    static HSSFCellStyle style;

    /**
     * 導出Excel
     *
     * @param sheetName sheet名稱
     * @param title     標題
     * @param values    內容
     * @param wb        HSSFWorkbook對象
     * @return
     */
    public static HSSFWorkbook getHSSFWorkbook(String sheetName, String[] title, List<Map<String, Object>> values, HSSFWorkbook wb) {
        // 第一步，創建一個HSSFWorkbook
        if (wb == null) {
            wb = new HSSFWorkbook();
            style = getStyle(wb);
            /*創建一個sheet*/
            HSSFSheet sheet = wb.createSheet(sheetName);
            /*設置標題*/
            setTitle(sheet, title);
            /*將map裏的數據設置到sheet 中去*/
            setData(sheet, values);
        } else {
            style = getStyle(wb);
            HSSFSheet sheet = wb.getSheet(sheetName);
            setTitle(sheet, title);
            setData(sheet, values);
        }
        return wb;
    }

    private static void setTitle(HSSFSheet sheet, String[] title) {
        int lastRowNum = sheet.getLastRowNum();
        /*獲取 最後一行的行號*/
        HSSFRow row = sheet.createRow(lastRowNum + 1);
        for (int i = 0; i < title.length; i++) {
            HSSFCell cell = row.createCell(i);
            cell.setCellValue(title[i]);
            cell.setCellStyle(style);
        }

    }

    /**
     * 構建樣式
     *
     * @param wb
     * @return
     */
    private static HSSFCellStyle getStyle(HSSFWorkbook wb) {
        HSSFCellStyle style = wb.createCellStyle();
        // 創建一個居中格式
        style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        return style;
    }

    /**
     * 填充數據的方法
     *
     * @param sheet
     * @param mapList
     */
    private static void setData(HSSFSheet sheet, List<Map<String, Object>> mapList) {
        int i = sheet.getLastRowNum();
        for (Map<String, Object> value : mapList) {
            HSSFRow row = sheet.createRow(i + 1);
            int j = 0;
            for (Map.Entry<String, Object> entry : value.entrySet()) {
                //將內容按順序賦給對應的列對象
                row.createCell(j).setCellValue((String) entry.getValue());
                j++;
            }
            i++;
        }
    }

    public static void main(String[] args) {
        String sheetName = "學生信息表";//Sheet名稱
        /*說明: 如果是用map的話 必須使用linkHashMap 這樣的數據纔是有序的,否則就是無序的*/
        Map<String, Object> map = new LinkedHashMap<>();
        List<Map<String, Object>> mapList = new ArrayList<>();
        map.put("name", "小明");
        map.put("sex", "男");
        map.put("age", "10");
        map.put("class", "廣東小學");
        map.put("school", "三年二班");
        mapList.add(map);
        String[] title = {"名稱", "性別", "年齡", "學校", "班級"};
        //excel文件名
        String fileName = "D://學生信息表" + System.currentTimeMillis() + ".xls";
        //第一次加載數據
        HSSFWorkbook workbook = getHSSFWorkbook(sheetName, title, mapList, null);
        //同一個sheet 中添加其他信息
        Map<String, Object> map1 = new LinkedHashMap<>();
        List<Map<String, Object>> mapList1 = new ArrayList<>();
        map1.put("hight", "165cm");
        map1.put("weight", "80kg");
        map1.put("like", "打籃球");
        mapList1.add(map1);
        String[] titles = {"身高", "體重", "愛好"};
        workbook = getHSSFWorkbook(sheetName, titles, mapList1, workbook);
        OutputStream os = null;
        try {
            os = new FileOutputStream(new File(fileName));
            workbook.write(os);
            os.flush();
            os.close();
            System.out.println("successful");
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }


}

#測試結果是

剛剛好滿足我的要求

補充: 由於寫日誌的時候快要下班了,但是啓動項目的時候發現一個異常, 異常就是springBoot 不兼容poi 3.6的版本,所以重新換了4.0.0的版本才得以生效

#貼出前端的代碼

/**
     * 導出excel表格
     *
     * @param request
     * @param response
     * @return
     * @author Lengff
     * @time 2018-11-1 18:43:06
     */
    @RequestMapping("export")
    @ResponseBody
    public void export(HttpServletRequest request, HttpServletResponse response) {
        String sheetName = "全站概況統計";
        String fileName = "全站概況統計" + System.currentTimeMillis() + ".xls";
        String[] title = {"統計", "新增激活設備", "新增註冊數", "新增註冊轉化率", "新增註冊數", "啓動量", "活躍啓動量", "平均啓動次數", "登錄人數", "登錄轉化率"};
        String[] titlB = {"統計", "累計激活設備", "累計註冊數", "註冊轉化率"};
        List<Map<String, Object>> todayCount = siteCountService.getTodayCount(1);
        HSSFWorkbook wb = ExcelUtil.getHSSFWorkbook(sheetName, title, todayCount, null);
        List<Map<String, Object>> countYesterday = siteCountService.getTodayCount(2);
        wb = ExcelUtil.getHSSFWorkbook(sheetName, title, countYesterday, wb);
        List<Map<String, Object>> countAll = siteCountService.countAll();
        wb = ExcelUtil.getHSSFWorkbook(sheetName, titlB, countAll, wb);
        try {
            this.setResponseHeader(response, fileName);
            OutputStream os = response.getOutputStream();
            wb.write(os);
            os.flush();
            os.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }


    //發送響應流方法
    private void setResponseHeader(HttpServletResponse response, String fileName) {
        try {
            try {
                fileName = new String(fileName.getBytes(), "ISO8859-1");
            } catch (UnsupportedEncodingException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            response.setContentType("application/octet-stream;charset=ISO8859-1");
            response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
            response.addHeader("Pargam", "no-cache");
            response.addHeader("Cache-Control", "no-cache");
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

成功的導出excel文件

#最後的結果

 

總結:excel 導出其實是用的比較多的功能 , 實現的方式也有很多種, 之前也做過很多種 , 但是覺得都挺麻煩的, 唯獨這次的方式比較方便, 因爲是把bean 轉成了map , 所以就不需要考慮 對應關係, 但是要注意的是必須是用linkHashMap 要不然就會亂序,一樣會讓人頭疼不已的!