Java implements exporting excel files

  4.0.0  org.springframework.boot spring-boot-starter-parent 2.2.6.RELEASE    com.briup demo3 0.0.1-SNAPSHOT war demo3 Demo project for Spring Boot  1.8    org.springframework.boot spring-boot-starter-web   org.springframework.boot spring-boot-starter-tomcat provided   org.springframework.boot spring-boot-starter-test test   org.junit.vintage junit-vintage-engine     org.apache.poi poi 3.6   javax.servlet servlet-api   log4j log4j        org.springframework.boot spring-boot-maven-plugin    

public class User { private String username; private String email; private String createTime; private String LastLoginTime; private String roleName; private String enable; public User() { super(); } }

import java.util.List; public interface UserService { public List findAllUser(); }

import java.util.List; public class UserServiceImpl implements UserService { @Override public List findAllUser() { User user = new User(); return null; } }

import java.util.List; import java.util.Map; import org.apache.poi.hssf.usermodel.HSSFCell; import org.apache.poi.hssf.usermodel.HSSFCellStyle; import org.apache.poi.hssf.usermodel.HSSFRow; import org.apache.poi.hssf.usermodel.HSSFSheet; import org.apache.poi.hssf.usermodel.HSSFWorkbook; public class ExcelUtil { public static HSSFWorkbook getHSSFWorkbook(String sheetName,String sheetName1,String sheetName2, String []title, String[] content,String[] app){ // 第一步，创建一个HSSFWorkbook，对应一个Excel文件 HSSFWorkbook wb = new HSSFWorkbook(); // 第二步，在workbook中添加一个sheet,对应Excel文件中的sheet HSSFSheet sheet = wb.createSheet(sheetName); HSSFSheet sheet1 = wb.createSheet(sheetName1); HSSFSheet sheet2 = wb.createSheet(sheetName2); // 第三步，在sheet中添加表头第0行,注意老版本poi对Excel的行数列数有限制 HSSFRow row = sheet.createRow(0); HSSFRow row1 = sheet1.createRow(0); HSSFRow row2 = sheet2.createRow(0); // 第四步，创建单元格样式，并设置值表头 设置表头居中 HSSFCellStyle style = wb.createCellStyle(); style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 创建一个居中格式 //声明单元格 HSSFCell cell = null; //创建标题 for(int i=0;i 0){ for(int i=0;i 0){ for(int i=0;i 0){ for(int i=0;i
        

         Copy after login
        
       

import java.io.OutputStream; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.List; import javax.servlet.http.HttpServletResponse; import org.apache.poi.hssf.usermodel.HSSFWorkbook; import org.springframework.util.StringUtils; import org.springframework.web.bind.annotation.RequestBody; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.ResponseBody; import org.springframework.web.bind.annotation.RestController; @RestController @RequestMapping("/MyTest") public class HelloController { @ResponseBody @RequestMapping("/hello") public void export(@RequestBody(required = false) User user,String username,HttpServletResponse response) throws Exception { if (user ==null && !StringUtils.isEmpty(username)){ //GET 请求的参数 user = new User(); user.setUsername(username); } UserService userService = new UserServiceImpl(); //获取数据 List list = userService.findAllUser(); //excel标题 String[] title = {"姓名", "邮箱", "创建时间", "最近登录时间","角色","是否可用"}; //excel文件名 String fileName = System.currentTimeMillis() + ".xls"; //sheet名 String sheetName = "用户信息"; String sheetName1 = "hello"; String sheetName2 = "xixi"; //没有数据就传入null吧，Excel工具类有对null判断 String[] content= {"ali","aaa","ddd","aaa","aaa","aaaa"}; String[] app= {"bbbb","bbbb","bbbb","bbbb","bbbb","bbbb",}; if (list != null && list.size() > 0){ SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); for (int i = 0; i < list.size(); i++) { User obj = list.get(i); content[1] = obj.getUsername(); content[1] = obj.getEmail(); content[2] = obj.getCreateTime() == null ? "" : sdf.format(obj.getCreateTime()); content[3] = obj.getLastLoginTime() == null ? "": sdf.format(obj.getLastLoginTime()); content[4] = obj.getRoleName(); } } if (list != null && list.size() > 0){ SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); for (int i = 0; i < list.size(); i++) { User obj = list.get(i); app[1] = obj.getUsername(); app[1] = obj.getEmail(); app[2] = obj.getCreateTime() == null ? "" : sdf.format(obj.getCreateTime()); app[3] = obj.getLastLoginTime() == null ? "": sdf.format(obj.getLastLoginTime()); app[4] = obj.getRoleName(); } } //创建HSSFWorkbook HSSFWorkbook wb = ExcelUtil.getHSSFWorkbook(sheetName,sheetName1,sheetName2, title, content,app); // HSSFWorkbook wb1 = ExcelUtil.getHSSFWorkbook(sheetName1, title, content); //响应到客户端 try { fileName = new String(fileName.getBytes(), "UTF-8"); response.setContentType("application/vnd.ms-excel;charset=utf-8"); response.setHeader("Content-Disposition", "attachment; filename=" + fileName); OutputStream os = response.getOutputStream(); wb.write(os); os.flush(); os.close(); } catch (Exception e) { e.printStackTrace(); } } }