java怎么下载（EasyExcel）

EasyExcel组件

EasyExcel是一个基于Java的简单、省内存的读写Excel的开源项目。在尽可能节约内存的情况下支持读写百M的Excel。

github地址：https://github.com/alibaba/easyexcel

坐标：

<dependency> <groupId>com.alibaba</groupId> <artifactId>easyexcel</artifactId> <version>2.1.6</version> </dependency>

Bean:

读Excel文件，案例：

文件内容：

代码案例：

package com.what21.easyexcel.demo; import com.alibaba.excel.EasyExcel; import com.alibaba.excel.context.AnalysisContext; import com.alibaba.excel.event.AnalysisEventListener; import com.alibaba.fastjson.JSON; import com.what21.easyexcel.model.Student; import java.util.ArrayList; import java.util.List; public class EasyExcelXlsxDemo { public static void main(String[] args) { // 读取文件（xls） // String fileName = "D:/demo.xls"; // 读取文件（xlsx） String fileName = "D:/demo.xlsx"; // 接收解析出的目标对象 List<Student> studentList = new ArrayList<>(); // 这里需要指定读用哪个class去读，然后读取第一个sheet文件流会自动关闭 // excel中表的列要与对象的字段相对应 EasyExcel.read(fileName, Student.class, new AnalysisEventListener<Student>() { @Override public void invoke(Student student, AnalysisContext analysisContext) { // 每解析一条数据都会调用该方法 System.out.println("Student对象：" + JSON.toJSONString(student)); studentList.add(student); } @Override public void doAfterAllAnalysed(AnalysisContext analysisContext) { // 解析完毕的回调方法 System.out.println("excel文件读取完毕！"); } }).sheet().doRead(); // 遍历访问 for (Student student : studentList) { System.out.println(student); } } }

写Excel文件，案例：

代码案例：

package com.what21.easyexcel.demo; import com.alibaba.excel.EasyExcel; import com.what21.easyexcel.model.Student; import java.util.ArrayList; import java.util.List; public class EasyExcelWriteDemo { public static void main(String[] args) { List<Student> dataList = new ArrayList<Student>(); for (int i = 1; i <= 10; i++) { Student student = new Student(); student.setSn(i); student.setStuName("name" + i); student.setAge(i + 20); student.setAddress("地址" + i); student.setMoney((float) i); dataList.add(student); } String fileName = "d://write.xlsx"; EasyExcel.write(fileName, Student.class).sheet("写入内容").doWrite(dataList); } }

文件内容：

填充Excel文件，案例：

文件模板：

代码案例：

package com.what21.easyexcel.demo; import com.alibaba.excel.EasyExcel; import lombok.Data; import java.util.HashMap; import java.util.Map; /** * 填充 */ public class EasyExcelFillDemo { public static void main(String[] args) { String templateFileName = "D:/template.xlsx"; // 根据模板填充内容并输出 String fileName = "D:/simple.1.xlsx"; FillData fillData = new FillData(); fillData.setId(1001); fillData.setName("名字"); EasyExcel.write(fileName).withTemplate(templateFileName).sheet(0).doFill(fillData); // 根据模板填充内容并输出 String fileName2 = "D:/simple.2.xlsx"; Map<String, Object> map = new HashMap<String, Object>(); map.put("name", "张三"); map.put("id", 1002); EasyExcel.write(fileName2).withTemplate(templateFileName).sheet().doFill(map); } @Data public static class FillData { private int id; private String name; } }

下载Excel文件，案例

代码案例：

package com.what21.easyexcel.controller; import com.alibaba.excel.EasyExcel; import com.what21.easyexcel.model.Student; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestMapping; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.net.URLEncoder; import java.util.ArrayList; import java.util.List; @Controller @RequestMapping("/download") public class DownloadController { @GetMapping("/demo1") public void demo(HttpServletResponse response) throws IOException { // ==========================================================================// // ====HTTP头设置 // ==========================================================================// response.setCharacterEncoding("UTF-8"); response.setContentType("application/vnd.ms-excel"); String fileName = "测试下载"; fileName = URLEncoder.encode(fileName, "UTF-8"); fileName = fileName.replaceAll("\\+", "%20"); response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + fileName + ".xlsx"); // ==========================================================================// // ====数据 // ==========================================================================// List<Student> dataList = new ArrayList<Student>(); for (int i = 1; i <= 10; i++) { Student student = new Student(); student.setSn(i); student.setStuName("name" + i); student.setAge(i + 20); student.setAddress("地址" + i); student.setMoney((float) i); dataList.add(student); } // ==========================================================================// // ====下载输出 // ==========================================================================// String sheetName = "学生列表"; EasyExcel.write(response.getOutputStream(), Student.class).sheet(sheetName).doWrite(dataList); } }

启动代码：

package com.what21.easyexcel; import com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceAutoConfigure; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration; import org.springframework.boot.autoconfigure.jdbc.DataSourceTransactionManagerAutoConfiguration; import org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration; import org.springframework.boot.autoconfigure.security.servlet.SecurityAutoConfiguration; @SpringBootApplication(exclude = { DataSourceAutoConfiguration.class, DataSourceTransactionManagerAutoConfiguration.class, DruidDataSourceAutoConfigure.class, HibernateJpaAutoConfiguration.class, SecurityAutoConfiguration.class}, scanBasePackages = {"com.what21.easyexcel"}) public class EasyExcelApplication { public static void main(String[] args) { SpringApplication.run(EasyExcelApplication.class, args); } }