poi操作excel

<!--poi-->
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>3.17</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>3.17</version>
        </dependency>

package com.zdyl.devicemanagement.common.utils;

import org.apache.poi.hssf.usermodel.*;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Map;

public class PoiUtils {

    /**
     * 导出Excel并下载
     *
     * @param response
     */
    public static void downLoadExcel(HttpServletResponse response, List<Map<String, Object>> deviceList) {
        SimpleDateFormat format = new SimpleDateFormat("yyyyMMddHHmmss");
        HSSFWorkbook workbook = new HSSFWorkbook();
        HSSFSheet sheet = workbook.createSheet("设备告警表");


        String fileName = "EquipmentAlarm" + format.format(new Date()) + ".xls";//设置要导出的文件的名字


        String[] headers = {"场站名称", "告警级别", "设备名称", "告警ID", "告警含义", "信号ID", "关联信号", "原始编码", "开始时间"};
        //headers表示excel表中第一行的表头

        HSSFRow row = sheet.createRow(0);
        //在excel表中添加表头

        for (int i = 0; i < headers.length; i++) {
            HSSFCell cell = row.createCell(i);
            HSSFRichTextString text = new HSSFRichTextString(headers[i]);
            cell.setCellValue(text);
        }
        //新增数据行，并且设置单元格数据
        int rowNum = 1;
        //在表中存放查询到的数据放入对应的列
        for (Map<String, Object> alarm : deviceList) {
            HSSFRow row1 = sheet.createRow(rowNum);
            if (alarm.get("StationName") == null || alarm.get("StationName").equals("")) {
                continue;
            }
            row1.createCell(0).setCellValue(alarm.get("StationName").toString());
            if (alarm.get("AlarmLevel") == null || alarm.get("AlarmLevel").equals("")) {
                continue;
            }
            row1.createCell(1).setCellValue(alarm.get("AlarmLevel").toString());
            if (alarm.get("DeviceName") == null || alarm.get("DeviceName").equals("")) {
                continue;
            }
            row1.createCell(2).setCellValue(alarm.get("DeviceName").toString());
            if (alarm.get("AlarmID") == null || alarm.get("AlarmID").equals("")) {
                continue;
            }
            row1.createCell(3).setCellValue(alarm.get("AlarmID").toString());
            if (alarm.get("Meanings") == null || alarm.get("Meanings").equals("")) {
                continue;
            }
            row1.createCell(4).setCellValue(alarm.get("Meanings").toString());
            if (alarm.get("SignalID") == null || alarm.get("SignalID").equals("")) {
                continue;
            }
            row1.createCell(5).setCellValue(alarm.get("SignalID").toString());
            if (alarm.get("SignalName") == null || alarm.get("SignalName").equals("")) {
                continue;
            }
            row1.createCell(6).setCellValue(alarm.get("SignalName").toString());
            if (alarm.get("OriginalNo") == null || alarm.get("OriginalNo").equals("")) {
                continue;
            }
            row1.createCell(7).setCellValue(alarm.get("OriginalNo").toString());
            if (alarm.get("StartTime") == null || alarm.get("StartTime").equals("")) {
                continue;
            }
//            SimpleDateFormat format1 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
//            SimpleDateFormat format2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
//            Date startTime = format1.parse(alarm.get("StartTime").toString());
            row1.createCell(8).setCellValue(alarm.get("StartTime").toString());
            rowNum++;
        }

        response.setContentType("application/octet-stream");
        response.setHeader("Content-disposition", "attachment;filename=" + fileName);
        try {
            response.flushBuffer();
            workbook.write(response.getOutputStream());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

 文件下载

/**
 * 图片下载
 */
public class ImageDowload {

    /**
     * @param imageUrl  图片地址
     * @param imageName 图片下载到本地的名称
     * @param response
     */
    public static void imageDowload(String imageUrl, String imageName, HttpServletResponse response, String format) throws IOException {
        File file = new File(imageUrl);
        FileInputStream fis = new FileInputStream(file);
        response.setContentType("application/force-download");
        response.addHeader("Content-disposition", "attachment;fileName=" + file.getName());
        OutputStream os = response.getOutputStream();
        byte[] buf = new byte[1024];
        int len = 0;
        while ((len = fis.read(buf)) != -1) {
            os.write(buf, 0, len);
        }
    }
}