java使用jxls导出excel功能

在java的开发里,导出excel功能会经常遇到的,而jxls框架提供了很大的方便.

jxls官网:http://jxls.sourceforge.net/,官网的下载包里面也提供详细的文档说明.

下文提供思路,主要以web项目导出excel来举例jxls用法,文末也贴一下java项目导出excel功能(这个简单一点)

直接贴关键代码(其它关于怎么用java config方式的spring mvc不做说明)
1.引用jxls依赖

<dependency>
<groupId>net.sf.jxls</groupId>
<artifactId>jxls-core</artifactId>
<version>1.0.5</version>
</dependency>

2.EmployeeController.java

package com.exam.web;
import com.exam.domain.Employee;
import net.sf.jxls.transformer.XLSTransformer;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.ss.usermodel.Workbook;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@Controller
@RequestMapping("/employee")
public class EmployeeController {
/**
* 这里接管了response,我们自己把response flush出去,所以返回类型是void(不要用什么String,否则会报响应已提交过的异常哦)
*/
@RequestMapping("/export")
public void export(HttpServletRequest request,HttpServletResponse response){
String templateFileName= request.getServletContext().getRealPath("/") + "/resources/templateFileName.xls";
String destFileName= "destFileName.xls";
//模拟数据
List<Employee> staff = new ArrayList<Employee>();
staff.add(new Employee("Derek", 35, 3000, 0.30));
staff.add(new Employee("Elsa", 28, 1500, 0.15));
staff.add(new Employee("Oleg", 32, 2300, 0.25));
Map<String,Object> beans = new HashMap<String,Object>();
beans.put("employees", staff);
XLSTransformer transformer = new XLSTransformer();
InputStream in=null;
OutputStream out=null;
//设置响应
response.setHeader("Content-Disposition", "attachment;filename=" + destFileName);
response.setContentType("application/vnd.ms-excel");
try {
in=new BufferedInputStream(new FileInputStream(templateFileName));
Workbook workbook=transformer.transformXLS(in, beans);
out=response.getOutputStream();
//将内容写入输出流并把缓存的内容全部发出去
workbook.write(out);
out.flush();
} catch (InvalidFormatException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (in!=null){try {in.close();} catch (IOException e) {}}
if (out!=null){try {out.close();} catch (IOException e) {}}
}
}
}

3.templateFileName.xls(内容是二进制,不容易贴出来)



这个JEXL语法和JSTL语法十分相似.

这里我们自己处理了Response,没必要交给spring的视图解析器.在返回响应前我们设置了响应的Header和ContentType以便客户端的浏览器解析为弹出下载.这里调用了transformer.transformXLS(in, beans)方法得到一个Workbook,这方法会把模板(至于模板怎么写,详细看官方文档)先读入到输入流再处理,再把Workbook的内容写入到输出流发送出去.

上文源码:http://download.csdn.net/detail/xiejx618/7836191

如果不想使用上面的模板，还有一种更灵活自定义的方法(比如编码定义excel样式,动态增加多个sheet等等),也可以在Controller方法直接返回AbstractXlsView.下面是一个例子:

@RequestMapping(value = "listXls",method = RequestMethod.GET)
public View listXls() {
List<User> list = getUsers();
return new AbstractXlsView() {
@Override
protected void buildExcelDocument(Map<String, Object> model, Workbook workbook, HttpServletRequest request, HttpServletResponse response) throws Exception {
addSheet(workbook.createSheet("UserStatistics1"), list.subList(0, 50));//不包括第50个
addSheet(workbook.createSheet("UserStatistics2"), list.subList(50,list.size()));
}
};
}

private List<User> getUsers() {
List<User> list = new ArrayList<>();
for (int i = 0; i < 103; i++) {
User user = new User();
user.setUsername("name" + i);
user.setPassword("pwd" + i);
user.setId((long) i);
list.add(user);
}
return list;
}

private void addSheet(Sheet sheet, List<User> list) {
int rowNum=0;
Row row0 = sheet.createRow(rowNum++);
row0.createCell(0).setCellValue("ID");
row0.createCell(1).setCellValue("Username");
row0.createCell(2).setCellValue("Password");
row0.createCell(3).setCellValue("Height");
for (User user : list) {
Row row = sheet.createRow(rowNum++);
row.createCell(0).setCellValue(user.getId());
row.createCell(1).setCellValue(user.getUsername());
row.createCell(2).setCellValue(user.getPassword());
row.createCell(3).setCellValue(user.getHeight());
}
}

顺便贴一下java项目(不是web项目)的例子源码:http://download.csdn.net/detail/xiejx618/7836227