超详细的java生成excel文件并下载
在网上随手一搜，可以搜到很多java生成excel文件相关的博客，但每个都有不同，核心点说清楚了，但具体运用的时候，相信大家或多或少都没法一次直接运用，这样每次去找并且运用的时候很费时间，所以这也是我觉得有必要写这个博客的原因
1、导入所需要的jar包
<!-- excel 引用包 -->
<dependency>
<groupId>net.sourceforge.jexcelapi</groupId>
<artifactId>jxl</artifactId>
<version>2.6.12</version>
</dependency>
2、编写所需要的类
package com.test.demo.controllers; import com.test.demo.domain.entities.Address; import com.test.demo.services.ExcelService; import jxl.Workbook; import jxl.format.Alignment; import jxl.format.Border; import jxl.format.BorderLineStyle; import jxl.format.Colour; import jxl.format.*; import jxl.format.VerticalAlignment; import jxl.write.*; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import org.springframework.web.context.request.RequestContextHolder; import org.springframework.web.context.request.ServletRequestAttributes; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.File; import java.io.FileInputStream; import java.io.InputStream; import java.io.OutputStream; import java.text.SimpleDateFormat; import java.util.List; /** * @author dyh * @create 2018-07-14 下午8:20 * @desc excle表格功能编写 **/ @RestController @RequestMapping("/excel") public class ExcelController { @Autowired private ExcelService excelService; /** * 下载文件 * * @return */ @RequestMapping({"/download"}) public void download() { ServletRequestAttributes requestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes(); HttpServletResponse response = requestAttributes.getResponse(); HttpServletRequest request = requestAttributes.getRequest(); // 文件名 String filename = "地址列表.xls"; try { // 写到服务器上 String path = request.getSession().getServletContext().getRealPath("") + "/" + filename; // 写到服务器上（这种测试过，在本地可以，放到linux服务器就不行） //String path = this.getClass().getClassLoader().getResource("").getPath()+"/"+filename; File name = new File(path); // 创建写工作簿对象 WritableWorkbook workbook = Workbook.createWorkbook(name); // 工作表 WritableSheet sheet = workbook.createSheet("地址列表", 0); // 设置字体; WritableFont font = new WritableFont(WritableFont.ARIAL, 14, WritableFont.BOLD, false, UnderlineStyle.NO_UNDERLINE, Colour.BLACK); WritableCellFormat cellFormat = new WritableCellFormat(font); // 设置背景颜色; cellFormat.setBackground(Colour.WHITE); // 设置边框; cellFormat.setBorder(Border.ALL, BorderLineStyle.DASH_DOT); // 设置文字居中对齐方式; cellFormat.setAlignment(Alignment.CENTRE); // 设置垂直居中; cellFormat.setVerticalAlignment(VerticalAlignment.CENTRE); // 分别给1,5,6列设置不同的宽度; sheet.setColumnView(0, 15); sheet.setColumnView(4, 60); sheet.setColumnView(5, 35); // 给sheet电子版中所有的列设置默认的列的宽度; sheet.getSettings().setDefaultColumnWidth(20); // 给sheet电子版中所有的行设置默认的高度，高度的单位是1/20个像素点,但设置这个貌似就不能自动换行了 // sheet.getSettings().setDefaultRowHeight(30 * 20); // 设置自动换行; cellFormat.setWrap(true); // 单元格 Label label0 = new Label(0, 0, "ID", cellFormat); Label label1 = new Label(1, 0, "省", cellFormat); Label label2 = new Label(2, 0, "市", cellFormat); Label label3 = new Label(3, 0, "区", cellFormat); Label label4 = new Label(4, 0, "详细地址", cellFormat); Label label5 = new Label(5, 0, "创建时间", cellFormat); sheet.addCell(label0); sheet.addCell(label1); sheet.addCell(label2); sheet.addCell(label3); sheet.addCell(label4); sheet.addCell(label5); // 给第二行设置背景、字体颜色、对齐方式等等; WritableFont font2 = new WritableFont(WritableFont.ARIAL, 14, WritableFont.NO_BOLD, false, UnderlineStyle.NO_UNDERLINE, Colour.BLACK); WritableCellFormat cellFormat2 = new WritableCellFormat(font2); // 设置文字居中对齐方式; cellFormat2.setAlignment(Alignment.CENTRE); // 设置垂直居中; cellFormat2.setVerticalAlignment(VerticalAlignment.CENTRE); cellFormat2.setBackground(Colour.WHITE); cellFormat2.setBorder(Border.ALL, BorderLineStyle.THIN); cellFormat2.setWrap(true); // 记录行数 int n = 1; // 查找所有地址 List<Address> addressList = excelService.findAll(); if (addressList != null && addressList.size() > 0) { // 遍历 for (Address a : addressList) { SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); String createTime = sdf.format(a.getCreateTime()); Label lt0 = new Label(0, n, a.getId() + "", cellFormat2); Label lt1 = new Label(1, n, a.getProvince(), cellFormat2); Label lt2 = new Label(2, n, a.getCity(), cellFormat2); Label lt3 = new Label(3, n, a.getArea(), cellFormat2); Label lt4 = new Label(4, n, a.getAddress(), cellFormat2); Label lt5 = new Label(5, n, createTime, cellFormat2); sheet.addCell(lt0); sheet.addCell(lt1); sheet.addCell(lt2); sheet.addCell(lt3); sheet.addCell(lt4); sheet.addCell(lt5); n++; } } //开始执行写入操作 workbook.write(); //关闭流 workbook.close(); } catch (Exception e) { e.printStackTrace(); } // 第六步，下载excel OutputStream out = null; try { // 1.弹出下载框，并处理中文 /** 如果是从jsp页面传过来的话，就要进行中文处理，在这里action里面产生的直接可以用 * String filename = request.getParameter("filename"); */ /** if (request.getMethod().equalsIgnoreCase("GET")) { filename = new String(filename.getBytes("iso8859-1"), "utf-8"); } */ response.addHeader("content-disposition", "attachment;filename=" + java.net.URLEncoder.encode(filename, "utf-8")); // 2.下载 out = response.getOutputStream(); String path3 = request.getSession().getServletContext().getRealPath("") + "/" + filename; // inputStream：读文件，前提是这个文件必须存在，要不就会报错 InputStream is = new FileInputStream(path3); byte[] b = new byte[4096]; int size = is.read(b); while (size > 0) { out.write(b, 0, size); size = is.read(b); } out.close(); is.close(); } catch (Exception e) { e.printStackTrace(); } } }
package com.test.demo.services; import com.test.demo.domain.entities.Address; import com.test.demo.domain.entities.AddressRepository; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import java.util.List; /** * @author dyh * @create 2018-07-14 下午9:21 * @desc excel测试类 **/ @Service public class ExcelService { @Autowired private AddressRepository addressRepository; /** * 得到所有地址列表 * * @return */ public List<Address> findAll(){ return addressRepository.findAll(); } }
3、配置文件
server.port=8025 spring.datasource.max-idle=10 spring.datasource.max-wait=10000 spring.datasource.min-idle=1 spring.datasource.initial-size=1 spring.datasource.validation-query=SELECT 1 spring.datasource.test-on-borrow=false spring.datasource.test-while-idle=true spring.datasource.time-between-eviction-runs-millis=18800 spring.datasource.url=@db.dyh2020.url@ spring.datasource.username=@db.dyh2020.username@ spring.datasource.password=@db.dyh2020.password@ spring.datasource.driver-class-name=com.mysql.jdbc.Driver spring.jpa.database=MYSQL # 显示后台处理的SQL语句 spring.jpa.show-sql=true # 自动检查实体和数据库表是否一致，如果不一致则会进行更新数据库表 spring.jpa.hibernate.ddl-auto=none
写好代码之后本地运行，在浏览器输入地址：http://localhost:8025/excel/download 即可看到下载的文件
github代码地址：https://github.com/DYH2020/springBootDemo
