excelUtil

excelUtil

util

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 cn.hutool.core.collection.CollUtil;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.apache.poi.ss.usermodel.Workbook;

import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Field;
import java.net.URLEncoder;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;

/**
 * @author why
 * @date 2023-02-21 11:24
 **/
@Slf4j
public class ExcelUtil {

    /**
     * 不可见字符
     */
    private static List<String> specialCode = new ArrayList<String>() {{
        add("\u200E");
    }};

    /**
     * 解析excel
     *
     * @param inputStream 文件流
     * @param sheetIndex  sheet页
     * @param pojoClass   实体类
     * @author why
     */
    public static <T> List<T> analysisExcel(InputStream inputStream, int sheetIndex, Class<T> pojoClass) {
        if (inputStream == null) return null;

        ImportParams params = new ImportParams();
        // 第几个sheet页
        params.setStartSheetIndex(sheetIndex);
        params.setNeedVerfiy(true);
        List<T> result = new ArrayList<>();
        try {
            List<T> list = ExcelImportUtil.importExcel(inputStream, pojoClass, params);
            for (T t : list) {
                if (!checkObjFieldIsNull(t)) {
                    result.add(t);
                }
            }
            if (CollUtil.isEmpty(list)) {
                log.error("导入数据不能为空");
            }
        } catch (NoSuchElementException e) {
            log.error("excel文件不能为空{}", e.getMessage());
        } catch (Exception e) {
            log.error("导入异常", e);
        }
        return result;
    }


    /**
     * 解析Excel
     *
     * @param file       文件
     * @param sheetIndex sheet页
     * @param pojoClass  实体类
     * @author why
     */
    public static <T> List<T> analysisExcel(File file, int sheetIndex, Class<T> pojoClass) {
        if (file == null) return null;
        ImportParams params = new ImportParams();
        params.setNeedVerfiy(true);
        // 第几个sheet页
        params.setStartSheetIndex(sheetIndex);
        List<T> result = new ArrayList<>();
        try {
            List<T> list = ExcelImportUtil.importExcel(file, pojoClass, params);
            for (T t : list) {
                if (!checkObjFieldIsNull(t)) {
                    result.add(t);
                }
            }
            if (CollUtil.isEmpty(list)) {
                log.error("导入数据不能为空");
            }
        } catch (NoSuchElementException e) {
            log.error("excel文件不能为空{}", e.getMessage());
        } catch (Exception e) {
            log.error("导入异常", e);
        }
        return result;
    }

    /**
     * excel 导出
     *
     * @param list     数据列表
     * @param fileName 导出时的excel名称
     * @param response 响应
     * @author why
     */
    public static void exportExcel(List<Map<String, Object>> list, String fileName, HttpServletResponse response) throws IOException {
        //把数据添加到excel表格中
        Workbook workbook = ExcelExportUtil.exportExcel(list, ExcelType.HSSF);
        downLoadExcel(fileName, response, workbook);
    }

    /**
     * excel 导出
     *
     * @param list      数据列表
     * @param pojoClass pojo类型
     * @param fileName  导出时的excel名称
     * @param response  响应
     * @author why
     */
    public static void exportExcel(List<?> list, Class<?> pojoClass, String fileName, HttpServletResponse response) throws IOException {
        ExportParams exportParams = new ExportParams();
        exportParams.setType(ExcelType.XSSF);
        exportExcel(list, pojoClass, fileName, response, exportParams);
    }

    /**
     * excel 导出
     *
     * @param list         数据列表
     * @param pojoClass    pojo类型
     * @param fileName     导出时的excel名称
     * @param response     响应
     * @param exportParams 导出参数（标题、sheet名称、是否创建表头，表格类型）
     * @author why
     */
    private static void exportExcel(List<?> list, Class<?> pojoClass, String fileName, HttpServletResponse response, ExportParams exportParams) throws IOException {
        //把数据添加到excel表格中
        Workbook workbook = ExcelExportUtil.exportExcel(exportParams, pojoClass, list);
        downLoadExcel(fileName, response, workbook);
    }


    /**
     * excel 导出
     *
     * @param list      数据列表
     * @param title     表格内数据标题
     * @param sheetName sheet名称
     * @param pojoClass pojo类型
     * @param fileName  导出时的excel名称
     * @param response  响应
     * @author why
     */
    public static void exportExcel(List<?> list, Class<?> pojoClass, String fileName, String title, String sheetName, HttpServletResponse response) throws IOException {
        ExportParams exportParams = new ExportParams(title, sheetName, ExcelType.XSSF);
        exportExcel(list, pojoClass, fileName, response, exportParams);
    }


    /**
     * excel 导出
     *
     * @param list           数据列表
     * @param title          表格内数据标题
     * @param sheetName      sheet名称
     * @param pojoClass      pojo类型
     * @param fileName       导出时的excel名称
     * @param isCreateHeader 是否创建表头
     * @param response       响应
     * @author why
     */
    public static void exportExcel(List<?> list, String title, String sheetName, Class<?> pojoClass, String fileName, boolean isCreateHeader, HttpServletResponse response) throws IOException {
        ExportParams exportParams = new ExportParams(title, sheetName, ExcelType.XSSF);
        exportParams.setCreateHeadRows(isCreateHeader);
        exportExcel(list, pojoClass, fileName, response, exportParams);
    }


    /**
     * excel下载
     *
     * @param fileName 下载时的文件名称
     * @param response 响应
     * @param workbook excel数据
     * @author why
     */
    private static void downLoadExcel(String fileName, HttpServletResponse response, Workbook workbook) throws IOException {
        try {
            String time = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyyMMddHHmmss"));

            response.setCharacterEncoding("UTF-8");
            response.setHeader("content-Type", "application/vnd.ms-excel");
            response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName + "_" + time + ".xlsx", "UTF-8"));
            response.setHeader("Access-Control-Expose-Headers", "Content-Disposition");
            workbook.write(response.getOutputStream());
        } catch (Exception e) {
            throw new IOException(e.getMessage());
        }
    }

    /**
     * 检查文件是否为空
     *
     * @param obj 文件
     * @author why
     */
    private static boolean checkObjFieldIsNull(Object obj) throws IllegalAccessException {
        if (obj == null) return true;

        boolean flag = true;
        for (Field f : obj.getClass().getDeclaredFields()) {
            f.setAccessible(true);
            Object o = f.get(obj);
            if (o != null) {
                flag = false;
            }
            if (o instanceof String) {
                for (String code : specialCode) {
                    o = o.toString().replaceAll(code, "");
                }
                o = StringUtils.isBlank((String) o) ? "" : ((String) o).trim();
                f.set(obj, o);
            }
        }
        return flag;
    }

}