Practical sharing of springboot+easypoi rapid business integration

        1. Dependency introduction

<!--引入EasyPOI-->
        <dependency>
            <groupId>cn.afterturn</groupId>
            <artifactId>easypoi-base</artifactId>
            <version>4.1.0</version>
        </dependency>
        <dependency>
            <groupId>cn.afterturn</groupId>
            <artifactId>easypoi-web</artifactId>
            <version>4.1.0</version>
        </dependency>
        <dependency>
            <groupId>cn.afterturn</groupId>
            <artifactId>easypoi-annotation</artifactId>
            <version>4.1.0</version>
        </dependency>

        2. Encapsulate easypoi tool class

package com.wzz.utils;

import cn.afterturn.easypoi.excel.ExcelExportUtil;
import cn.afterturn.easypoi.excel.ExcelImportUtil;
import cn.afterturn.easypoi.excel.entity.ExportParams;
import cn.afterturn.easypoi.excel.entity.ImportParams;
import cn.afterturn.easypoi.excel.entity.enmus.ExcelType;
import org.apache.commons.lang3.StringUtils;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.ss.usermodel.Workbook;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.IOException;
import java.net.URLEncoder;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;

/**
 * Excel导入导出工具类
 * @author pangu
 */
public class ExcelUtil {

    /**
     * 导出工具类
     * @param list
     * @param title
     * @param sheetName
     * @param pojoClass
     * @param fileName
     * @param isCreateHeader
     * @param response
     */
    public static void exportExcel(List<?> list, String title, String sheetName, Class<?> pojoClass,
                                   String fileName, boolean isCreateHeader, HttpServletResponse response){
        ExportParams exportParams = new ExportParams(title, sheetName);
        exportParams.setCreateHeadRows(isCreateHeader);
        defaultExport(list, pojoClass, fileName, response, exportParams);
    }

    /**
     * 导出工具类
     * @param list
     * @param title
     * @param sheetName
     * @param pojoClass
     * @param fileName
     * @param response
     */
    public static void exportExcel(List<?> list, String title, String sheetName, Class<?> pojoClass,String fileName,
                                   HttpServletResponse response){
        ExportParams exportParams = new ExportParams(title, sheetName);
        exportParams.setStyle(ExcelStyleUtil.class);
        defaultExport(list, pojoClass, fileName, response, exportParams);
    }

    public static void exportExcel(List<Map<String, Object>> list, String fileName, HttpServletResponse response){
        defaultExport(list, fileName, response);
    }

    private static void defaultExport(List<?> list, Class<?> pojoClass, String fileName,
                                      HttpServletResponse response, ExportParams exportParams) {
        //TODO设置标题颜色

        Workbook workbook = ExcelExportUtil.exportExcel(exportParams,pojoClass,list);
        if (workbook != null); downLoadExcel(fileName, response, workbook);
    }

    private static void downLoadExcel(String fileName, HttpServletResponse response, Workbook workbook) {
        try {
            response.setCharacterEncoding("UTF-8");
            response.setHeader("content-Type", "application/vnd.ms-excel");
            response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8"));
            workbook.write(response.getOutputStream());
        } catch (IOException e) {
            //throw new NormalException(e.getMessage());
        }
    }

    private static void defaultExport(List<Map<String, Object>> list, String fileName, HttpServletResponse response) {
        Workbook workbook = ExcelExportUtil.exportExcel(list, ExcelType.HSSF);
        if (workbook != null);
        downLoadExcel(fileName, response, workbook);
    }

    public static <T> List<T> importExcel(String filePath,Integer titleRows,Integer headerRows, Class<T> pojoClass){
        if (StringUtils.isBlank(filePath)){
            return null;
        }
        ImportParams params = new ImportParams();
        params.setTitleRows(titleRows);
        params.setHeadRows(headerRows);
        List<T> list = null;
        try {
            list = ExcelImportUtil.importExcel(new File(filePath), pojoClass, params);
        }catch (NoSuchElementException e){
            //throw new NormalException("模板不能为空");
        } catch (Exception e) {
            e.printStackTrace();
            //throw new NormalException(e.getMessage());
        } return list;
    }

    public static <T> List<T> importExcel(MultipartFile file, Integer titleRows, Integer headerRows, Class<T> pojoClass){
        if (file == null){ return null;
        }
        ImportParams params = new ImportParams();
        params.setTitleRows(titleRows);
        params.setHeadRows(headerRows);
        List<T> list = null;
        try {
            list = ExcelImportUtil.importExcel(file.getInputStream(), pojoClass, params);
        }catch (NoSuchElementException e){
            // throw new NormalException("excel文件不能为空");
        } catch (Exception e) {
            //throw new NormalException(e.getMessage());
            System.out.println(e.getMessage());
        }
        return list;
    }

}

        3.Controller layer directly calls

/**
     * 导出Excel   excelVo
     * 注意这里暂时只能用get方法，不能用post
     */
    @GetMapping("/exportExcel")
    @ApiOperation("根据过滤条件导出excel数据")
    public void exportExcel(HttpServletResponse response,
                            @RequestParam(name = "pageNo") int pageNo,
                            @RequestParam("pageSize") int pageSize,
                            @RequestParam(name = "unit",required = false) String unit,
                            @RequestParam(name = "username",required = false) String username,
                            @RequestParam(name = "truename",required = false) String truename,
                            @RequestParam(name = "date",required = false) String date) throws IOException {
            Evorecorddto queryInfo = new Evorecorddto();
            queryInfo.setPageNo(pageNo);
            queryInfo.setPageSize(pageSize);
            if (unit !=null){
                queryInfo.setUnit(unit);
            }
            if (username!=null){
                queryInfo.setUsername(username);
            }
            if (truename!=null){
                queryInfo.setTruename(truename);
            }
            if (date!=null){
                ObjectMapper objectMapper = new ObjectMapper();
                Evorecorddto.DateRange dateRange = objectMapper.readValue(date, Evorecorddto.DateRange.class);
                queryInfo.setDate(dateRange);
            }

        // 查询所有答题用户列表
        List<excelVo> records = evaluationService.excelprint(queryInfo);

        ExcelUtil.exportExcel(records, null, "答题排名", excelVo.class, "答题排名", response);
    }

In addition, if you need to modify the excel export color, you can modify the official interface provided.

        4. Modify the interface

package com.wzz.utils;

import cn.afterturn.easypoi.excel.entity.params.ExcelExportEntity;
import cn.afterturn.easypoi.excel.entity.params.ExcelForEachParams;
import cn.afterturn.easypoi.excel.export.styler.IExcelExportStyler;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.ss.usermodel.*;

/**
 * @author:Kevin
 * @create: 2023-08-24 10:14
 * @Description:
 */

public class ExcelStyleUtil implements IExcelExportStyler {
    // 数据行类型
    private static final String DATA_STYLES = "dataStyles";
    // 标题类型
    private static final String TITLE_STYLES = "titleStyles";
    //数据行样式
    private CellStyle styles;
    // 标题样式
    private CellStyle titleStyle;

    public ExcelStyleUtil(Workbook workbook) {
        this.init(workbook);
    }

    private void init(Workbook workbook) {
        this.styles = initStyles(workbook);
        this.titleStyle = initTitleStyle(workbook);
    }


    @Override
    public CellStyle getHeaderStyle(short i) {
        return null;
    }

    @Override
    public CellStyle getTitleStyle(short i) {
        return titleStyle;
    }

    @Override
    public CellStyle getStyles(boolean b, ExcelExportEntity excelExportEntity) {
        return styles;
    }

    @Override
    public CellStyle getStyles(Cell cell, int i, ExcelExportEntity excelExportEntity, Object o, Object o1) {
        return getStyles(true,excelExportEntity);
    }

    @Override
    public CellStyle getTemplateStyles(boolean b, ExcelForEachParams excelForEachParams) {
        return null;
    }

    /**
     * 初始化--标题行样式
     * @param workbook
     * @return
     */
    private CellStyle initTitleStyle(Workbook workbook) {
        return buildCellStyle(workbook,TITLE_STYLES);
    }

    /**
     * 初始化--数据行样式
     * @param workbook
     * @return
     */
    private CellStyle initStyles(Workbook workbook) {
        return buildCellStyle(workbook,DATA_STYLES);
    }

    /**
     * 设置单元格样式
     * @param workbook
     * @param type 类型  用来区分是数据行样式还是标题样式
     * @return
     */
    private CellStyle buildCellStyle(Workbook workbook,String type) {
        CellStyle style = workbook.createCellStyle();
        // 字体样式
        Font font = workbook.createFont();
        if(TITLE_STYLES.equals(type)){
            // 背景色
            style.setFillForegroundColor(IndexedColors.SKY_BLUE.getIndex());
            style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
            font.setFontHeightInPoints((short)12);
            font.setBold(true);
            font.setColor(HSSFColor.HSSFColorPredefined.BLUE.getIndex());

        }
        if(DATA_STYLES.equals(type)){
            font.setFontHeightInPoints((short)10);
        }
        font.setFontName("Courier New");
        style.setFont(font);
        // 设置底边框
        style.setBorderBottom(BorderStyle.THIN);
        // 设置左边框
        style.setBorderLeft(BorderStyle.THIN);
        // 设置右边框;
        style.setBorderRight(BorderStyle.THIN);
        // 设置顶边框;
        style.setBorderTop(BorderStyle.THIN);
        // 设置底边颜色
        style.setBottomBorderColor(HSSFColor.HSSFColorPredefined.BLACK.getIndex());
        // 设置左边框颜色;
        style.setLeftBorderColor(HSSFColor.HSSFColorPredefined.BLACK.getIndex());
        // 设置右边框颜色;
        style.setRightBorderColor(HSSFColor.HSSFColorPredefined.BLACK.getIndex());
        // 设置顶边框颜色;
        style.setTopBorderColor(HSSFColor.HSSFColorPredefined.BLACK.getIndex());
        // 设置自动换行;
        style.setWrapText(false);
        // 设置水平对齐的样式为居中对齐;
        style.setAlignment(HorizontalAlignment.CENTER);
        // 设置垂直对齐的样式为居中对齐;
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        return style;
    }

}

        5. Front-end code

//导出excel
    exportExcel(){
      //https://slgstu.top/api/common/exportExcel
      axios.get("https://slgstu.top/api/common/exportExcel",{
        params: this.queryInfo,
        headers: { 'Content-Type': 'application/json,charset=utf-8'},
        responseType: 'blob', //二进制流
      }).then(res => {
        console.log(res)
        this.$notify({
          title: '提示',
          message: '正在导出，请稍等！'
        });
        // console.log(res);
        // let blob = new Blob([res], { type: 'application/vnd.ms-excel,charset=utf-8' });
        // let url =window.URL.createObjectURL(blob);
        // let link = document.createElement('a');
        // link.download = '答题记录.xlsx';
        // link.href = url;
        // link.click();
        downloadFile(res.data, "答题排名", 'xlsx')
      });
    },