Spring Boot + Easy Excel 自定义复杂样式导入导出

tips：能用模板就用模板，当模板不适用的情况下，再选择自定义生成 Excel。

官网：https://easyexcel.opensource.alibaba.com

安装

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>easyexcel</artifactId>
            <version>3.1.1</version>
        </dependency>

一、处理自定义导出复杂场景

1、列不固定，动态列
2、动态下拉
3、自定义锁定行/列，添加密码
4、合并单元格
5、导入自定义统一注解统一校验
6、样式处理（字体，颜色，底色，富文本，列宽，行宽等）
7、冻结窗格
8、多Sheet处理

1、列不固定，动态列

• 首先定义一个公共实体，处理公共字段和动态列字段，具体实体则继承该类即可。

package com.example.springbootexcel.excel.base.model;

import com.alibaba.excel.annotation.ExcelProperty;
import lombok.Data;

import java.util.List;
import java.util.Map;

@Data
public class BaseExcel {

    @ExcelProperty( value = "序号")
    private String num;

    /**
     * 动态字段处理
     */
    private List<Map<String, Object>> dynamicList;

}

2、动态下拉

封装一个公共类，构造入参Map，key为表头，value为下拉字符串数组。
.registerWriteHandler(new DropDownHandler(dropDownMap));

package com.example.springbootexcel.excel.base.style;

import com.alibaba.excel.write.handler.SheetWriteHandler;
import com.alibaba.excel.write.metadata.holder.WriteSheetHolder;
import com.alibaba.excel.write.metadata.holder.WriteWorkbookHolder;
import org.apache.poi.ss.usermodel.DataValidation;
import org.apache.poi.ss.usermodel.DataValidationConstraint;
import org.apache.poi.ss.usermodel.DataValidationHelper;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.util.CellRangeAddressList;

import java.util.Map;

/**
 * 添加下拉选单
 *
 * @author jason
 */
public class DropDownHandler implements SheetWriteHandler {
    private final Map<Integer, String[]> dropDownMap;  // key:列号(从0开始), value:下拉数据

    public DropDownHandler(Map<Integer, String[]> dropDownMap) {
        this.dropDownMap = dropDownMap;
    }

    @Override
    public void beforeSheetCreate(WriteWorkbookHolder writeWorkbookHolder, WriteSheetHolder writeSheetHolder) {
        // 不需要实现
    }

    @Override
    public void afterSheetCreate(WriteWorkbookHolder writeWorkbookHolder, WriteSheetHolder writeSheetHolder) {
        if (dropDownMap == null || dropDownMap.isEmpty()) {
            return;
        }

        Sheet sheet = writeSheetHolder.getSheet();
        DataValidationHelper helper = sheet.getDataValidationHelper();

        dropDownMap.forEach((columnIndex, dropDownData) -> {
            // 设置下拉框数据范围 (这里设置从第2行到第10000行)
            CellRangeAddressList addressList = new CellRangeAddressList(1, 9999, columnIndex, columnIndex);

            // 创建数据验证约束
            DataValidationConstraint constraint = helper.createExplicitListConstraint(dropDownData);

            // 创建数据验证
            DataValidation validation = helper.createValidation(constraint, addressList);

            // 阻止输入非下拉选项的值
            validation.setErrorStyle(DataValidation.ErrorStyle.STOP);
            validation.setShowErrorBox(true);
            validation.setSuppressDropDownArrow(true);
            validation.createErrorBox("提示", "请从下拉选项中选择");

            // 添加验证到sheet
            sheet.addValidationData(validation);
        });
    }
}

3、自定义锁定行/列，添加密码

@Override
    public void afterCellCreate(CellWriteHandlerContext context) {
        WriteSheetHolder writeSheetHolder = context.getWriteSheetHolder();
        Sheet sheet = writeSheetHolder.getSheet();
        Workbook workbook = sheet.getWorkbook();
        Cell cell = context.getCell();
        int columnIndex = cell.getColumnIndex();
        Row row = cell.getRow();

        // 设置工作表保护
        if (!sheet.getProtect()) {
            XSSFSheet xssfSheet = (XSSFSheet) sheet;
            // 启用保护
            xssfSheet.protectSheet("1234");
            // 设置保护选项：允许删除未锁定行
            xssfSheet.lockDeleteRows(false);
            // 设置保护选项：允许插入未锁定行
            xssfSheet.lockInsertRows(false);
        }

        // 设置工作表的默认单元格样式为不锁定
        CellStyle defaultStyle = workbook.createCellStyle();
        defaultStyle.setLocked(false);
        sheet.setDefaultColumnStyle(columnIndex, defaultStyle);
        row.setRowStyle(defaultStyle);
    }

4、合并单元格

sheet.addMergedRegion(new CellRangeAddress(relativeRowIndex, relativeRowIndex, 0, 10));

5、导入自定义统一注解统一校验

package com.example.springbootexcel.excel.base.component;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * tips：非必填校验，填了就校验，不填不校验
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD})
public @interface ExcelValidation {

    /**
     * 日期校验
     *
     * @return true表示必须为日期，false表示不限制
     */
    boolean date() default false;

    /**
     * 是否必须为数字
     *
     * @return true表示必须为数字，false表示不限制
     */
    boolean numeric() default false;

    /**
     * 是否允许小数，且最多两位小数
     *
     * @return true表示允许最多两位小数，false表示不允许小数
     */
    boolean decimal() default false;

    /**
     * 是否允许斜杠
     *
     * @return true表示允许斜杠，false表示不允许
     */
    boolean allowSlash() default false;

    /**
     * 校验失败时的错误提示信息
     *
     * @return 错误提示信息
     */
    String message() default "字段校验失败";

}

6、样式处理（字体，颜色，底色，富文本，列宽，行宽等）

// 基本样式设置
        cellStyle.setBorderTop(BorderStyle.THIN);
        cellStyle.setBorderBottom(BorderStyle.THIN);
        cellStyle.setBorderLeft(BorderStyle.THIN);
        cellStyle.setBorderRight(BorderStyle.THIN);
        // 设置水平对齐为左对齐
        cellStyle.setAlignment(HorizontalAlignment.LEFT);
        // 设置垂直对齐为垂直居中
        cellStyle.setVerticalAlignment(VerticalAlignment.CENTER);
        // 设置自动换行
        cellStyle.setWrapText(true);

        // 创建默认字体
        Font defaultFont = workbook.createFont();
        defaultFont.setFontName(DEFAULT_FONT_NAME);
        defaultFont.setFontHeightInPoints(DEFAULT_FONT_POINTS);
        defaultFont.setColor(IndexedColors.BLACK.getIndex());
        defaultFont.setBold(false);

        // 创建红色字体
        Font redFont = workbook.createFont();
        redFont.setFontName(DEFAULT_FONT_NAME);
        redFont.setFontHeightInPoints(DEFAULT_FONT_POINTS);
        redFont.setColor(IndexedColors.RED.getIndex());
        redFont.setBold(true);

        // 自定义列宽
        String cellValue = cell.getStringCellValue();
        Integer columnWidth = COLUMN_WIDTHS.get(cellValue);
        if (ObjectUtil.isNotNull(columnWidth) && !CollectionUtil.contains(COLUMN_WIDTHS_EXIST, context.getColumnIndex())) {
            sheet.setColumnWidth(context.getColumnIndex(), columnWidth);
            COLUMN_WIDTHS_EXIST.add(context.getColumnIndex());
        }
        // 设置默认宽度
        if (!CollectionUtil.contains(COLUMN_WIDTHS_EXIST, context.getColumnIndex())) {
            sheet.setColumnWidth(context.getColumnIndex(), DEFAULT_COLUMN_WIDTH);
        }

        // 提示词
        if (CollectionUtil.contains(TIPS_LIST, relativeRowIndex)) {
            defaultFont = redFont;
            // 合并单元格
            sheet.addMergedRegion(new CellRangeAddress(relativeRowIndex, relativeRowIndex, 0, 10));
        }
        // 表头
        if (CollectionUtil.contains(HEAD_LIST, relativeRowIndex)) {
            defaultFont.setBold(true);
            // 背景色
            cellStyle.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());
            cellStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND);

            // 动态字段标红
            if (CollectionUtil.contains(HEAD_READ_COLOR, cell.getColumnIndex())) {
                defaultFont = redFont;
            } else {
                // 星号标红
                RichTextString richText = cell.getRichStringCellValue();
                if (StrUtil.startWith(cellValue, "*")) {
                    richText.applyFont(0, 1, redFont);
                    if (cellValue.length() > 1) {
                        richText.applyFont(1, cellValue.length(), defaultFont);
                    }
                    cell.setCellValue(richText);
                }
            }
        }
        cellStyle.setFont(defaultFont);

7、冻结窗格

.registerWriteHandler(new FreezePaneHandler(2))

package com.example.springbootexcel.excel.base.style;

import com.alibaba.excel.write.handler.SheetWriteHandler;
import com.alibaba.excel.write.metadata.holder.WriteSheetHolder;
import com.alibaba.excel.write.metadata.holder.WriteWorkbookHolder;
import org.apache.poi.ss.usermodel.Sheet;

/**
 * 冻结窗格
 *
 * @author jason
 */
public class FreezePaneHandler implements SheetWriteHandler {
    private final int row;  // 需要冻结的行

    public FreezePaneHandler(int row) {
        this.row = row;
    }

    @Override
    public void beforeSheetCreate(WriteWorkbookHolder writeWorkbookHolder, WriteSheetHolder writeSheetHolder) {
    }

    @Override
    public void afterSheetCreate(WriteWorkbookHolder writeWorkbookHolder, WriteSheetHolder writeSheetHolder) {
        Sheet sheet = writeSheetHolder.getSheet();
        // 冻结首行
        // sheet.createFreezePane(0, 1, 0, 1);

        sheet.createFreezePane(0, row, 0, row);
    }

}

8、多Sheet处理

        // 创建 ExcelWriter 对象
        ExcelWriter excelWriter = EasyExcel.write(filePath).inMemory(true).build();

        // 写入第1个 Sheet
        WriteSheet sheet1 = EasyExcel.writerSheet("Sheet1")
                .registerWriteHandler(new CommonStyleHandler(MockDataUtil.getHeadReadColor(headList, dynamicList)))
                .registerWriteHandler(new DropDownHandler(dropDownMap))
                .registerWriteHandler(new FreezePaneHandler(2))
                .build();
        excelWriter.write(sheet1DataList, sheet1);

        // 写入第2个 Sheet
        WriteSheet sheet2 = EasyExcel.writerSheet("Sheet2")
                .head(BrandModelExcel.class)
                .registerWriteHandler(new FreezePaneHandler(1))
                .build();
        excelWriter.write(MockDataUtil.brandModelExcelList(), sheet2);

        // 写入第3个 Sheet
        WriteSheet sheet3 = EasyExcel.writerSheet("Sheet3")
                .head(VehicleNameExcel.class)
                .registerWriteHandler(new FreezePaneHandler(1))
                .build();
        excelWriter.write(MockDataUtil.vehicleNameExcelList(), sheet3);

        // 非常重要：最后一定要关闭 excelWriter
        excelWriter.finish();

        log.info("导出成功：{}", filePath);

源码：https://gitee.com/zhaomingjian/workspace_dora/tree/master/spring-boot-excel