Java中实现简单的Excel导出

简单介绍一下Java中的Excel文件导出功能（基于HttpServletResponse实现下载）

首先，引入需要依赖的jar包：

<dependency>
	<groupId>org.apache.poi</groupId>
	<artifactId>poi</artifactId>
	<version>3.14</version>
</dependency>
<dependency>
	<groupId>org.apache.poi</groupId>
	<artifactId>poi-ooxml</artifactId>
	<version>3.14</version>
</dependency>

编写一个工具类：

package exceloutput;

import org.apache.commons.lang3.StringUtils;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.streaming.SXSSFSheet;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.List;
import java.util.UUID;

/**
 * @author haozz
 * @date 2018/6/6 9:57
 * @description excel导出抽象工具类
 */
public abstract class ExportAbstractUtil {

    public void write(HttpServletResponse response, Workbook workbook){
        String fileName = UUID.randomUUID().toString()+".xls";
        pwrite(response,workbook,fileName);
    }

    public void write(HttpServletResponse response,Workbook workbook,String fileName){
        if(StringUtils.isEmpty(fileName)){
            fileName = UUID.randomUUID().toString()+".xls";
        }
        pwrite(response,workbook,fileName);
    }

    public void write(HttpServletResponse response, List<List<String>> lists,String fileName){
        if(StringUtils.isEmpty(fileName)){
            fileName = UUID.randomUUID().toString()+".xls";
        }
        SXSSFWorkbook workbook = new SXSSFWorkbook(lists.size());
        SXSSFSheet sheet = workbook.createSheet(fileName.substring(0,fileName.indexOf(".xls")));
        Integer rowIndex = 0;
        Row row = null;
        Cell cell = null;
        for(List<String> rowData: lists ){
            Integer columnIndex = 0;
            row = sheet.createRow(rowIndex++);
            for(String columnVal:rowData){
                cell = row.createCell(columnIndex++);
                cell.setCellValue(columnVal);

            }
        }
        pwrite(response,workbook,fileName);
    }

    private void pwrite(HttpServletResponse response,Workbook workbook,String fileName){
        response.setCharacterEncoding("UTF-8");
        response.setContentType("application/vnd.ms-excel;charset=UTF-8");
        try {
            response.addHeader("Content-Disposition", "attachment; filename="+new String(fileName.getBytes("UTF-8"),"ISO8859-1"));
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
            fileName= UUID.randomUUID().toString()+".xls";
            response.addHeader("Content-Disposition", "attachment; filename="+fileName);
        }
        try {
            workbook.write(response.getOutputStream());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

有了这个工具类就可以实现Excel导出了，代码不难，这里就不多解释了。

在SpringBoot项目中编写一个导出Excel的Controller，并继承上面的ExportAbstractUtil，给出一个接口用作测试：

package com.csdn.myboot.controller;

import com.csdn.myboot.utils.ExportAbstractUtil;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.servlet.http.HttpServletResponse;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/**
 * @author haozz
 * @date 2018/6/6 10:14
 * @description
 */
@Controller
@RequestMapping(value = "/index")
public class HelloCtrl extends ExportAbstractUtil{

    @RequestMapping(value = "/testExcelOutPut")
    @ResponseBody
    public void testExcelOutPut(HttpServletResponse response){
        //拼接数据start
        List<List<String>> lists = new ArrayList<List<String>>();
        String rows[] = {"year","month","day"};
        List<String> rowsTitle  = Arrays.asList(rows);
        lists.add(rowsTitle);
        for(int i = 0; i<=9;i++){
            String [] rowss = {"1","2","3"};
            List<String> rowssList = Arrays.asList(rowss);
            lists.add(rowssList);
        }
        //拼接数据end
        write(response,lists,"导出Excel.xls");
    }
}

浏览器输入链接：

http://localhost:8099/index/testExcelOutPut

即可自动下载测试数据组成的Excel：

参考文章：https://www.jianshu.com/p/d6a037a7e9d9