@Api(description = “导出excel”)
@RestController
@Log4j2
@RequestMapping(“export”)
public class PoiController {
@ApiOperation(“导出”)
@RequestMapping( method = RequestMethod.GET)
public MelotResult index(HttpServletResponse response) throws IOException {
List studentList = getStudentList();
//1.创建workbook工作簿
Workbook wb = new XSSFWorkbook();
createFirstSheet(wb,studentList);
response.setContentType(“application/vnd.ms-excel;chartset=utf-8”);
String fileName = URLEncoder.encode(“汇总”, “UTF8”);
response.setHeader(“Content-Disposition”, “attachment;filename=”+fileName + “.xlsx”);
ServletOutputStream out=response.getOutputStream();
wb.write(out);
out.flush();
out.close();
return new MelotResult<>("");
}
public List getStudentList(){
Student student = new Student();
student.setId(1L);
student.setAge(10);
student.setName(“one”);

    Student student1 = new Student();student1.setId(2L);student1.setAge(11);student1.setName("two");Student student2 = new Student();student2.setId(2L);student2.setAge(11);student2.setName("two");ArrayList<Student> list = Lists.newArrayList();list.add(student);list.add(student1);list.add(student2);return  list;}
public  void createFirstSheet(Workbook wb, List<Student> studentList ){//2.创建表单SheetSheet sheet = wb.createSheet("sheet1");//合并单元格CellRangeAddress region =new CellRangeAddress(0, 0, 0, 2);sheet.addMergedRegion(region);CellStyle cellStyle = wb.createCellStyle();for (int i =0;i<20;i++){sheet.setColumnWidth(i, 5000);//设置列的宽度是31个字符宽度}Row row = sheet.createRow(0);row.setHeightInPoints(50);//设置行的高度是50个点//创建单元格样式对象Cell cell = row.createCell(0);cellStyle.setAlignment(HorizontalAlignment.CENTER);//水平居中cellStyle.setVerticalAlignment(VerticalAlignment.CENTER);//垂直居中//设置单元格样式cell.setCellStyle(cellStyle);cell.setCellValue("学生明细表");Row row1 = sheet.createRow(1);Cell cell1 = row1.createCell(0);cell1.setCellValue("id");Cell cell2 = row1.createCell(1);cell2.setCellValue("年龄");Cell cell3 = row1.createCell(2);cell3.setCellValue("姓名");int rowNum = 2;for (Student student : studentList) {Row sheetRow= sheet.createRow(rowNum);Cell cell4 = sheetRow.createCell(0);cell4.setCellValue(student.getId());Cell cell5 = sheetRow.createCell(1);cell5.setCellValue(student.getAge());Cell cell6 = sheetRow.createCell(2);cell6.setCellValue(student.getName());rowNum++;}
}

}