基于Spring Mvc实现的Excel文件上传下载
最近工作遇到一个需求，需要下载excel模板，编辑后上传解析存储到数据库。因此为了更好的理解公司框架，我就自己先用spring mvc实现了一个样例。
基础框架
之前曾经介绍过一个最简单的spring mvc的项目如何搭建，传送门在这里。
这次就基于这个工程，继续实现上传下载的小例子。需要做下面的事情：
- 1 增加index.html，添加form提交文件
- 2 引入commons-fileupload、commons-io、jxl等工具包
- 3 创建upload download接口
- 4 注入multipartResolver bean
- 5 在upload中使用HttpServletRequest获取文件流，通过WorkBook进行解析
- 6 在download中通过HttpServerResponse返回文件流，实现下载
页面
页面很简单，其实就是一个form标签，需要注意的是：
- form中enctype="multipart/form-data"
- action指定访问的url
- input中需要设置name属性，这样后端才能获取到文件对象
<form role="form" action="/upload" method="POST" enctype="multipart/form-data">
<div class="form-group">
<label for="file">上传文件</label>
<input type="file" id="file" name="file">
</div>
<button type="submit" class="btn btn-default">提交</button>
</form>
引入commons-fileupload、jxl等工具包
涉及的jar包有：
- commons-fileupload 用于获取上传文件
- jxl 用于解析excel
<!-- springframework begins -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>4.2.4.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.2.4.RELEASE</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>4.0.0-b01</version>
</dependency>
<!-- https://mvnrepository.com/artifact/commons-io/commons-io -->
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.5</version>
</dependency>
<!-- https://mvnrepository.com/artifact/commons-fileupload/commons-fileupload -->
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3.2</version>
</dependency>
<!-- https://mvnrepository.com/artifact/jexcelapi/jxl -->
<dependency>
<groupId>jexcelapi</groupId>
<artifactId>jxl</artifactId>
<version>2.6</version>
</dependency>
Xml的配置
在web.xml中需要配置默认的访问页面，因为之前已经设置过拦截的请求是/，因此如果不设置所有的静态页面都会被拦截下来。
<welcome-file-list>
<welcome-file>index.html</welcome-file>
</welcome-file-list>
在spring的配置文件中，加入CommonsMultipartResolver的bean。
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<!-- set the max upload size100MB -->
<property name="maxUploadSize">
<value>104857600</value>
</property>
<property name="maxInMemorySize">
<value>4096</value>
</property>
</bean>
上传代码
@RequestMapping("upload")
public void upload(HttpServletRequest request, HttpServletResponse response) throws IOException, BiffException, WriteException {
MultipartHttpServletRequest mRequest = (MultipartHttpServletRequest) request;
MultipartFile file = mRequest.getFile("file");
Workbook workbook = Workbook.getWorkbook(file.getInputStream());
//遍历Sheet页
Arrays.stream(workbook.getSheets())
.forEach(sheet -> {
int size = sheet.getRows();
for(int i=0; i<size; i++){
//遍历每一行，读取每列信息
Arrays.stream(sheet.getRow(i)).forEach(cell -> System.out.println(cell.getContents().equals("")?'空':cell.getContents()));
}
});
response.setHeader("Content-Disposition", "attachment; filename=return.xls");
WritableWorkbook writableWorkbook = ExcelUtils.createTemplate(response.getOutputStream());
writableWorkbook.write();
writableWorkbook.close();
}
下载代码
@RequestMapping("download")
public void download(HttpServletRequest request, HttpServletResponse response) throws IOException, BiffException, WriteException {
response.setHeader("Content-Disposition", "attachment; filename=template.xls");
WritableWorkbook writableWorkbook = ExcelUtils.createTemplate(response.getOutputStream());
writableWorkbook.write();
writableWorkbook.close();
}
模板类
static class ExcelUtils {
public static WritableWorkbook createTemplate(OutputStream output) throws IOException, WriteException {
WritableWorkbook writableWorkbook= Workbook.createWorkbook(output);
WritableSheet wsheet = writableWorkbook.createSheet("测试title", 0);
CellFormat cf = writableWorkbook.getSheet(0).getCell(1, 0).getCellFormat();
WritableCellFormat wc = new WritableCellFormat();
// 设置居中
wc.setAlignment(Alignment.CENTRE);
// 设置边框线
// wc.setBorder(Border.ALL, BorderLineStyle.THIN);
wc.setBackground(jxl.format.Colour.GREEN);
Label nc0 = new Label(0, 0, "标题1",wc);//Label(x,y,z)其中x代表单元格的第x+1列，第y+1行, 单元格的内容是z
Label nc1 = new Label(1, 0, "标题2",wc);
Label nc2 = new Label(2, 0, "标题3",wc);
Label nc3 = new Label(0, 1, "dddd");
Label nc4 = new Label(1, 1, "ffff");
wsheet.addCell(nc0);
wsheet.addCell(nc1);
wsheet.addCell(nc2);
wsheet.addCell(nc3);
wsheet.addCell(nc4);
return writableWorkbook;
}
}
最后贡献下相关的代码
有需要的可以拿去参考
