异常代码

package org.springblade.modules.api.utils;

import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.support.ExcelTypeEnum;
import com.alibaba.excel.write.builder.ExcelWriterBuilder;
import com.alibaba.excel.write.metadata.WriteSheet;
import com.alibaba.excel.write.metadata.fill.FillConfig;
import com.alibaba.excel.write.metadata.fill.FillWrapper;
import com.alibaba.excel.write.metadata.style.WriteCellStyle;
import com.alibaba.excel.write.style.HorizontalCellStyleStrategy;
import com.alibaba.fastjson.JSON;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.usermodel.WorkbookFactory;
import org.springblade.modules.api.entity.LedgerObserve;
import org.springblade.modules.api.vo.LedgerObserveVO;
import org.springframework.core.io.ClassPathResource;

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

public class ExcelExporterUtil {

    /**
     * @param response         响应
     * @param templateFilePath 模版路径
     * @param inputFileName    导出文件名
     * @param List             数据列表
     * @param map              单个对象
     * @param sheetAt          第几个sheet
     * @param row              第几行开始
     * @throws Exception
     */
    public static void exportExcel(HttpServletResponse response, String templateFilePath, String inputFileName, List<?> List, Map<String, Object> map, Integer sheetAt, Integer row) throws Exception {
        response.setContentType("application/vnd.ms-excel");
        response.setCharacterEncoding("utf-8");
        // 这里URLEncoder.encode可以防止中文乱码 当然和easyexcel没有关系
        String fileNamePath = URLEncoder.encode(inputFileName, "UTF-8");
        response.setHeader("Content-disposition", "attachment;filename=" + fileNamePath + ".xlsx");
        //内容样式
        WriteCellStyle contentWriteCellStyle = ExcelMergeUtil.getContentWriteCellStyleTaiZhang();
        HorizontalCellStyleStrategy horizontalCellStyleStrategy = new HorizontalCellStyleStrategy(null, contentWriteCellStyle);
        int rowHeight = getFourthRowHeightFromTemplate(templateFilePath, sheetAt, row);
        InputStream is = getInputStream(templateFilePath);
        ExcelWriter excelWriter = EasyExcel.write(response.getOutputStream()).withTemplate(is)
                .registerWriteHandler(new CustomRowHeightHandler(rowHeight))
                .registerWriteHandler(horizontalCellStyleStrategy)
                .excelType(ExcelTypeEnum.XLS)
                .build();
        WriteSheet writeSheet = EasyExcel.writerSheet().build();
        // 先填充map中的变量
        excelWriter.fill(map, writeSheet);
        // 填充列表数据
        FillConfig fillConfig = FillConfig.builder().forceNewRow(Boolean.TRUE).build();
        excelWriter.fill(List, fillConfig, writeSheet);

        excelWriter.finish();

    }

    public static int getFourthRowHeightFromTemplate(String templateFilePath, Integer sheetAt, Integer row) throws Exception {
        InputStream is = getInputStream(templateFilePath);
        Workbook workbook = WorkbookFactory.create(is);
        Sheet sheet = workbook.getSheetAt(sheetAt); // 第一个工作表
        Row fourthRow = sheet.getRow(row); // 第四行（索引从0开始）
        int rowHeight = fourthRow.getHeight();
        workbook.close();
        return rowHeight;
    }

    public static InputStream getInputStream(String templateFilePath) throws Exception {
        ClassPathResource res = new ClassPathResource(templateFilePath);
        InputStream is = res.getInputStream();
        return is;
    }

}

策略代码

 /**
     * 内容样式
     *
     * @return
     */
    public static WriteCellStyle getContentWriteCellStyleTaiZhang() {
        //内容策略
        WriteCellStyle contentWriteCellStyle = new WriteCellStyle();
        // 必须设置字体（避免NPE）
        WriteFont font = new WriteFont();
        font.setFontName("宋体");
        font.setFontHeightInPoints((short) 14);
        font.setColor(IndexedColors.BLACK.getIndex());
        contentWriteCellStyle.setWriteFont(font); // 关键：字体不能为null
        //设置 水平居中
        contentWriteCellStyle.setHorizontalAlignment(HorizontalAlignment.CENTER);
        //自动换行
        contentWriteCellStyle.setWrapped(true);
        //垂直居中
        contentWriteCellStyle.setVerticalAlignment(VerticalAlignment.CENTER);
        //设置左边框
        contentWriteCellStyle.setBorderLeft(BorderStyle.THIN);
        //设置右边框
        contentWriteCellStyle.setBorderRight(BorderStyle.THIN);
        //设置上边框
        contentWriteCellStyle.setBorderTop(BorderStyle.THIN);
        //设置下边框
        contentWriteCellStyle.setBorderBottom(BorderStyle.THIN);
        return contentWriteCellStyle;
    }