java使用POI，以excel文件的形式，导出前端表格数据

Posted 2020-11-18 shuaifing

知识点：前端表格数据，调用后台接口，导出excel文件数据，使用到Apache POI接口

    POI提供API给Java程序对Microsoft Office格式档案读和写的功能。

 

（1）在pom.xml中引入POI和文件读写相关的包

 

<dependency>
    <groupId>commons-io</groupId>
    <artifactId>commons-io</artifactId>
</dependency>

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

 

（2）Controller层，表格导出接口

 

/**
 * 导出数据
 */
@RequestMapping("/Export")
public void export(HttpServletRequest request,HttpServletResponse response){
    Export<Equipment> ee = new Export<Equipment>();//equipment实体类
    List<Equipment> equiplist = equipmentService.getEquipmentList();  //equiplist是查询的数据集合
    String [] headers = {"e_id","e_code","e_location","e_ip","e_attend_code","cruser","crtime","upuser","uptime"};//表格头数据设置
    String fileName = "设备列表数据"; //excel表格名称
    response.setContentType("application/x-msdownload");
   ServletOutputStream outputStream = null;  //outputStream文件输出流
    try
    {
        fileName = fileName + ".xls";// 定义文件格式 
        if (request.getHeader("USER-AGENT").toLowerCase().contains("firefox"))// 火狐
        {
            response.setHeader("Content-Disposition",
                    "attachment;fileName=" + new String(fileName.getBytes("UTF-8"), "ISO-8859-1"));
        }
        else
        {
            response.setHeader("Content-Disposition",
                    "attachment;fileName=" + URLEncoder.encode(fileName, "UTF-8"));
        }
        outputStream = response.getOutputStream();
        try {
            ee.Export(headers, fileName, equiplist, outputStream);//表格导出工具类
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }
    }
    catch (UnsupportedEncodingException e)
    {
        throw new BusinessException("导出失败!");
    }
    catch (IOException e)
    {
        throw new BusinessException("导出失败!");
    }
    catch (NoSuchMethodException e)
    {
        LOGGER.error(e.getMessage());
    }
    catch (IllegalAccessException e)
    {
        LOGGER.error(e.getMessage());
    } finally
    {
        IOUtils.closeQuietly(outputStream);//
    }
}

（3）Export.java 表格导出工具类

package com.agesun.attendance.common;
import java.io.OutputStream;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Iterator;
import java.util.List;

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

/**
 * <一句话功能简述> <功能详细描述>
 *
 * @author nishuai
 * @version [版本号, 2018年06月14日]
 * @see [相关类/方法]
 * @since [产品/模块版本]
 */
public class Export<T>
{
    public void Export(String[] headers, String fileName, List<T> dataset, OutputStream outputStream)
        throws NoSuchMethodException, InvocationTargetException, IllegalAccessException
    {
        // 声明一个工作薄
        HSSFWorkbook wb = new HSSFWorkbook();
        // 声明一个单子并命名
        HSSFSheet sheet = wb.createSheet(fileName);
        
        /****************** 头部样式 ***********************/
        HSSFFont font = wb.createFont();
        font.setFontName("微软雅黑");
        font.setFontHeightInPoints((short)14);// 设置字体大小
        font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
        // 给单子名称一个长度
        sheet.setDefaultColumnWidth((short)16);
        // 生成一个样式
        HSSFCellStyle style = wb.createCellStyle();
        style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 居中
        style.setFont(font);
        /********************* 数据单元格样式 **************************/
        HSSFFont rowFont = wb.createFont();
        rowFont.setFontName("宋体");
        rowFont.setFontHeightInPoints((short)14);// 设置字体大小
        // 给单子名称一个长度
        sheet.setDefaultColumnWidth((short)16);
        // 生成一个样式
        HSSFCellStyle rowStyle = wb.createCellStyle();
        rowStyle.setFont(rowFont);
        // 样式字体居中
        rowStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        
        // 创建第一行（也可以称为表头）
        HSSFRow row = sheet.createRow(0);
        row.setHeight((short)500);
        // 给表头第一行一次创建单元格
        for (short i = 0; i < headers.length; i++)
        {
            HSSFCell cell = row.createCell(i);
            cell.setCellValue(headers[i]);
            cell.setCellStyle(style);
        }

      // 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);
            row.setHeight((short)500);
            T t = it.next();
            // 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 < headers.length; i++)
       {
          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;
        // 其它数据类型都当作字符串简单处理
        if (value != null && !"".equals(value))
        {
            textValue = value.toString();
        }
        if (textValue != null)
        {
            HSSFCell cell = row.createCell(i);
            cell.setCellStyle(rowStyle);
            cell.setCellValue(textValue);
        }
    }
}