知識點：前端表格數據，調用後臺接口，導出excel文件數據，使用到Apache POI接口

POI提供API給Java程序對Microsoft Office格式檔案讀和寫的功能。

（1）在pom.xml中引入POI和文件讀寫相關的包

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

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

（2）Controller層，表格導出接口

/**
 * 導出數據
 */
@RequestMapping("/Export")
public void export(HttpServletRequest request,HttpServletResponse response){
    Export<Equipment> ee = new Export<Equipment>();//equipment實體類
    List<Equipment> equiplist = equipmentService.getEquipmentList();  //equiplist是查詢的數據集合
 

    String [] headers = {"e_id","e_code","e_location","e_ip","e_attend_code","cruser","crtime","upuser","uptime"};//表格頭數據設置
    String fileName = "設備列表數據"; //excel表格名稱
    response.setContentType("application/x-msdownload");
   ServletOutputStream outputStream = null;  //outputStream文件輸出流
    try
    {
        fileName = fileName + ".xls";// 定義文件格式
 
 
        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);//表格導出工具類
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }
    }
    catch (UnsupportedEncodingException e)
    {
        throw new BusinessException("導出失敗!");
    }
    catch (IOException e)
    {
        throw new BusinessException("導出失敗!");
    }
    catch (NoSuchMethodException e)
    {
        LOGGER.error(e.getMessage());
    }
    catch (IllegalAccessException e)
    {
        LOGGER.error(e.getMessage());
    } finally
    {
        IOUtils.closeQuietly(outputStream);//
    }
}

（3）Export.java 表格導出工具類

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;

/**
 * <一句話功能簡述> <功能詳細描述>
 *
 * @author nishuai
 * @version [版本號, 2018年06月14日]
 * @see [相關類/方法]
 * @since [產品/模塊版本]
 */
public class Export<T>
{
    public void Export(String[] headers, String fileName, List<T> dataset, OutputStream outputStream)
        throws NoSuchMethodException, InvocationTargetException, IllegalAccessException
    {
        // 聲明一個工作薄
        HSSFWorkbook wb = new HSSFWorkbook();
        // 聲明一個單子並命名
        HSSFSheet sheet = wb.createSheet(fileName);
        
        /****************** 頭部樣式 ***********************/
        HSSFFont font = wb.createFont();
        font.setFontName("微軟雅黑");
        font.setFontHeightInPoints((short)14);// 設置字體大小
        font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
        // 給單子名稱一個長度
        sheet.setDefaultColumnWidth((short)16);
        // 生成一個樣式
        HSSFCellStyle style = wb.createCellStyle();
        style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 居中
        style.setFont(font);
        /********************* 數據單元格樣式 **************************/
        HSSFFont rowFont = wb.createFont();
        rowFont.setFontName("宋體");
        rowFont.setFontHeightInPoints((short)14);// 設置字體大小
        // 給單子名稱一個長度
        sheet.setDefaultColumnWidth((short)16);
        // 生成一個樣式
        HSSFCellStyle rowStyle = wb.createCellStyle();
        rowStyle.setFont(rowFont);
        // 樣式字體居中
        rowStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        
        // 創建第一行（也可以稱為表頭）
        HSSFRow row = sheet.createRow(0);
        row.setHeight((short)500);
        // 給表頭第一行一次創建單元格
        for (short i = 0; i < headers.length; i++)
        {
            HSSFCell cell = row.createCell(i);
            cell.setCellValue(headers[i]);
            cell.setCellStyle(style);
        }

      // 遍歷集合數據，產生數據行
        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，根據javabean屬性的先後順序，動態調用getXxx()方法得到屬性值    
          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[] {});
        // 判斷值的類型後進行強制類型轉換
       String textValue = null;
        // 其它數據類型都當作字符串簡單處理
        if (value != null && !"".equals(value))
        {
            textValue = value.toString();
        }
        if (textValue != null)
        {
            HSSFCell cell = row.createCell(i);
            cell.setCellStyle(rowStyle);
            cell.setCellValue(textValue);
        }
    }
}

java使用POI，以excel文件的形式，導出前端表格數據