EasyExcel导出合并单元格

Posted 2023-04-02 是一个菜鸟程序员啊

功能展示

功能类似这样：

开题序言

当时网上的资料大部分都是上下行相同的数据合并，唯独没有左右列的单元格合并。因此找资料花了一点时间，但功夫不负有心人，终于看到有两个和我要的功能差不多类似的文章。需要自取：

EasyExcel模板导出(行和列自动合并)_Lzfnemo2009的博客-CSDN博客_easyexcel模板导出

EasyExcel导出自定义合并单元格 策略 个人理解

写这篇文章只是为了自己以后参考。 

以下进入正文：

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1、导出的实体类，也就是表头

@Data
public class CityCapacityPo 

   
    @ExcelProperty(value = "时间",index = 0)
    private String time;

   
    @ExcelProperty(value = "出口",index = 1)
    private String export;

   
    @ExcelProperty(value = "地市",index = 2)
    private String direction;

   
    @ExcelProperty(value = "数据1",index = 3)
    private Double data1;

    
    @ExcelProperty(value = "数据2",index = 4)
    private Double data2;

    
    @ExcelProperty(value = "数据3",index = 5)
    private Double data3;

    
    @ExcelProperty(value = "数据4",index = 6)
    private Double data4;

    @ExcelProperty(value = "数据5",index = 7)
    private Double data5;

    @ExcelProperty(value = "数据6",index = 8)
    private Double data6;

2、行合并工具类

public class ExcelFillCellMergeStrategyUtils implements CellWriteHandler 

    /**
     * 需要合并列的下标，从0开始
     */
    private int[] mergeColumnIndex;
    /**
     * 从第几行开始合并，表头下标为0
     */
    private int mergeRowIndex;

    public ExcelFillCellMergeStrategyUtils(int mergeRowIndex, int[] mergeColumnIndex) 
        this.mergeRowIndex = mergeRowIndex;
        this.mergeColumnIndex = mergeColumnIndex;
    

    @Override
    public void beforeCellCreate(WriteSheetHolder writeSheetHolder, WriteTableHolder writeTableHolder, Row row, Head head, Integer integer, Integer integer1, Boolean aBoolean) 

    

    @Override
    public void afterCellCreate(WriteSheetHolder writeSheetHolder, WriteTableHolder writeTableHolder, Cell cell, Head head, Integer integer, Boolean aBoolean) 

    

    @Override
    public void afterCellDataConverted(WriteSheetHolder writeSheetHolder, WriteTableHolder writeTableHolder, CellData cellData, Cell cell, Head head, Integer integer, Boolean aBoolean) 

    

    @Override
    public void afterCellDispose(WriteSheetHolder writeSheetHolder, WriteTableHolder writeTableHolder, List<CellData> list, Cell cell, Head head, Integer integer, Boolean aBoolean) 

        //当前行
        int curRowIndex = cell.getRowIndex();
        //当前列
        int curColIndex = cell.getColumnIndex();

        if (curRowIndex > mergeRowIndex) 
            for (int i = 0; i < mergeColumnIndex.length; i++) 
                if (curColIndex == mergeColumnIndex[i]) 
                    mergeWithPrevRow(writeSheetHolder, cell, curRowIndex, curColIndex);
                    break;
                
            
        

    

    private void mergeWithPrevRow(WriteSheetHolder writeSheetHolder, Cell cell, int curRowIndex, int curColIndex) 
        //获取当前行的当前列的数据和上一行的当前列列数据，通过上一行数据是否相同进行合并
        Object curData = cell.getCellTypeEnum() == CellType.STRING ? cell.getStringCellValue() :
                cell.getNumericCellValue();
        Row preRow = cell.getSheet().getRow(curRowIndex - 1);
        if (preRow == null) 
            // 当获取不到上一行数据时，使用缓存sheet中数据
            preRow = writeSheetHolder.getCachedSheet().getRow(curRowIndex - 1);
        
        Cell preCell=preRow.getCell(curColIndex);
        Object preData = preCell.getCellTypeEnum() == CellType.STRING ? preCell.getStringCellValue() :
                preCell.getNumericCellValue();
        // 比较当前行的第一列的单元格与上一行是否相同，相同合并当前单元格与上一行
        if (curData.equals(preData)) 
            Sheet sheet = writeSheetHolder.getSheet();
            List<CellRangeAddress> mergeRegions = sheet.getMergedRegions();
            boolean isMerged = false;
            for (int i = 0; i < mergeRegions.size() && !isMerged; i++) 
                CellRangeAddress cellRangeAddr = mergeRegions.get(i);
                // 若上一个单元格已经被合并，则先移出原有的合并单元，再重新添加合并单元
                if (cellRangeAddr.isInRange(curRowIndex - 1, curColIndex)) 
                    sheet.removeMergedRegion(i);
                    cellRangeAddr.setLastRow(curRowIndex);
                    sheet.addMergedRegion(cellRangeAddr);
                    isMerged = true;
                
            
            // 若上一个单元格未被合并，则新增合并单元
            if (!isMerged) 
                CellRangeAddress cellRangeAddress = new CellRangeAddress(curRowIndex - 1, curRowIndex, curColIndex,
                        curColIndex);
                sheet.addMergedRegion(cellRangeAddress);
            
        





    

3、列合并的工具类

@Data
@AllArgsConstructor
public class CellLineRange 

    /**
     * 起始列
     */
    private int firstCol;

    /**
     * 结束列
     */
    private int lastCol;

public class ExcelFillCelMergeStrategy implements CellWriteHandler 

    //自定义合并单元格的列 如果想合并   第4列和第5例 、第6列和第7例： [CellLineRange(firstCol=3, lastCol=4), CellLineRange(firstCol=5, lastCol=6)]
    private List<CellLineRange> cellLineRangeList;

    //自定义合并单元格的开始的行  一般来说填表头行高0 表示从表头下每列开始合并 ：如表头行高位为3则 int mergeRowIndex = 2  ;
    private int mergeRowIndex;

    public ExcelFillCelMergeStrategy(List<CellLineRange> cellLineRangeList, int mergeRowIndex) 
        this.cellLineRangeList=cellLineRangeList;
        this.mergeRowIndex=mergeRowIndex;
    

    @Override
    public void beforeCellCreate(WriteSheetHolder writeSheetHolder, WriteTableHolder writeTableHolder, Row row, Head head, Integer integer, Integer integer1, Boolean aBoolean) 

    

    @Override
    public void afterCellCreate(WriteSheetHolder writeSheetHolder, WriteTableHolder writeTableHolder, Cell cell, Head head, Integer integer, Boolean aBoolean) 

    

    @Override
    public void afterCellDataConverted(WriteSheetHolder writeSheetHolder, WriteTableHolder writeTableHolder, CellData cellData, Cell cell, Head head, Integer integer, Boolean aBoolean) 

    

    @Override
    public void afterCellDispose(WriteSheetHolder writeSheetHolder, WriteTableHolder writeTableHolder, List<CellData> list, Cell cell, Head head, Integer integer, Boolean aBoolean) 

        //当前单元格的行数
        int curRowIndex = cell.getRowIndex();
        // 当前单元格的列数
        int curColIndex = cell.getColumnIndex();
        if (curRowIndex > mergeRowIndex) 
            if (curRowIndex > mergeRowIndex) 
                for (int i = 0; i < cellLineRangeList.size(); i++) 
                    if (curColIndex > cellLineRangeList.get(i).getFirstCol()&&curColIndex<=cellLineRangeList.get(i).getLastCol()) 
                        //单元格数据处理
                        mergeWithLeftLine(writeSheetHolder, cell, curRowIndex, curColIndex);
                        break;
                    
                
            
        
    

    /**
     * @description 当前单元格向左合并
     */
    private void mergeWithLeftLine(WriteSheetHolder writeSheetHolder, Cell cell, int curRowIndex, int curColIndex) 
        //当前单元格中数据
        Object curData = cell.getCellTypeEnum() == CellType.STRING ? cell.getStringCellValue() : cell.getNumericCellValue();
        //获取当前单元格的左面一个单元格
        Cell leftCell = cell.getSheet().getRow(curRowIndex).getCell(curColIndex - 1);
        //获取当前单元格的左面一个单元格中的数据
        Object leftData = leftCell.getCellTypeEnum() == CellType.STRING ? leftCell.getStringCellValue() : leftCell.getNumericCellValue();

        // 将当前单元格数据与左侧一个单元格数据比较
        if (leftData.equals(curData)) 
            //获取当前sheet页
            Sheet sheet = writeSheetHolder.getSheet();
            //得到所有的合并单元格
            List<CellRangeAddress> mergeRegions = sheet.getMergedRegions();
            //是否合并
            boolean isMerged = false;
            for (int i = 0; i < mergeRegions.size() && !isMerged; i++) 
                //CellRangeAddress POI合并单元格
                //CellRangeAddress(int firstRow, int lastRow, int firstCol, int lastCol)
                //例子：CellRangeAddress（2, 6000, 3, 3）；
                //第2行起 第6000行终止 第3列开始 第3列结束。
                CellRangeAddress cellRangeAddr = mergeRegions.get(i);
                // cellRangeAddr.isInRange(int rowInd, int colInd)确定给定坐标是否在此范围的范围内。
                // 若左侧一个单元格已经被合并，则先移出原有的合并单元，再重新添加合并单元
                if (cellRangeAddr.isInRange(curRowIndex, curColIndex - 1)) 
                    sheet.removeMergedRegion(i);
                    cellRangeAddr.setLastColumn(curColIndex);
                    sheet.addMergedRegion(cellRangeAddr);
                    isMerged = true;
                
            
            // 若左侧一个单元格未被合并，则新增合并单元
            if (!isMerged) 
                CellRangeAddress cellRangeAddress = new CellRangeAddress(curRowIndex , curRowIndex, curColIndex- 1, curColIndex);
                sheet.addMergedRegion(cellRangeAddress);
            
        

    

4、调用工具类，开始合并：

@PostMapping("/exportCityOutletCapacityList")
@ApiOperation("导出Excel表")
public void exportCityOutletCapacityList(@RequestBody OutletCapacityParam param, HttpServletResponse response) 
         //获取需要导出的表数据
         List<CityCapacityPo> list=capacityFlowDao.selectCityOutletCapacityList(param);
 try 
            String fileName = "测试合并单元格";
            response.setContentType("application/octet-stream");
            response.setCharacterEncoding("utf-8");
            response.setHeader("Content-disposition", "attachment;filename=" + fileName + ".xlsx");

            CityCapacityPo capacityPo=new CityCapacityPo();
            capacityPo.setExport("汇总");
            capacityPo.setTime("汇总");
            capacityPo.setDirection("汇总");
            //遍历列表，求各数据汇总
            capacityPo.setData1(list.stream().filter(Po-> Po.getData1()!=null).mapToDouble(CityCapacityPo::getData1).sum());
            capacityPo.setData2(list.stream().filter(Po-> Po.getData2()!=null).mapToDouble(CityCapacityPo::getData2).sum());
            capacityPo.setData3(list.stream().filter(Po-> Po.getData3()!=null).mapToDouble(CityCapacityPo::getData3).sum());
            capacityPo.setData4(list.stream().filter(Po-> Po.getData4()!=null).mapToDouble(CityCapacityPo::getData4).sum());
            capacityPo.setData5(list.stream().filter(Po-> Po.getData5()!=null).mapToDouble(CityCapacityPo::getData5).sum());
            capacityPo.setData6(list.stream().filter(Po-> Po.getData6()!=null).mapToDouble(CityCapacityPo::getData6).sum());
            list.add(capacityPo);

            ArrayList<CellLineRange> cellLineRanges=new ArrayList<>();
            //设置第几列开始合并
            int[] mergeColumnIndex = 0, 1;
            //设置第几行开始合并
            int mergeRowIndex = 1;


            cellLineRanges.add(new CellLineRange(0,2));
                EasyExcel.write(response.getOutputStream())              
                        //设置行合并单元格
                        .registerWriteHandler(new ExcelFillCellMergeStrategyUtils(mergeRowIndex,mergeColumnIndex))
                        //设置行合并单元格
                        .registerWriteHandler(new ExcelFillCelMergeStrategy(cellLineRanges,list.size()-1))
                        .head(CityCapacityPo.class)
                        .sheet("sheet1")
                        .doWrite(list);

         catch (Exception e) 
            e.printStackTrace();
        

    

---

以上就是行和列的合并过程了，主要的内容就是行和列合并的工具类，网上的资料都差不多。其实很多我确实也没参透，只是依样画葫芦，碰巧实现了。

EasyExcel单元格数据超过32767报错问题处理

EasyExcel单元格数据超过32767报错问题处理

EasyExcel描述

EasyExcel是一款基于Java的简单、省内存的读写Excel的开源项目。官网。使用起来确实比较方便，但是对于一些比较复杂的场景，比如多单元格，现在的版本兼容不是很好，不过效率和使用上确实体验还可以。

问题描述

不过今天在做一个数据量很大的Excel表导出的时候，遇到一个异常，这个字段数据量太多了，导出时候直接抛出如下异常：

IllegalArgumentException: The maximum length of cell contents (text) is 32,767 characters

看起来好像是超过框架限制了

在poi3.7.1版本找到代码org.apache.poi.hssf.usermodel.HSSFCell#setCellValue(org.apache.poi.ss.usermodel.RichTextString)：

public void setCellValue(RichTextString value)
    
        int row=_record.getRow();
        short col=_record.getColumn();
        short styleIndex=_record.getXFIndex();
        if (value == null)
        
            notifyFormulaChanging();
            setCellType(CellType.BLANK, false, row, col, styleIndex);
            return;
        

        if(value.length() > SpreadsheetVersion.EXCEL97.getMaxTextLength())
            throw new IllegalArgumentException("The maximum length of cell contents (text) is 32,767 characters");
        

        if (_cellType == CellType.FORMULA) 
            // Set the 'pre-evaluated result' for the formula
            // note - formulas do not preserve text formatting.
            FormulaRecordAggregate fr = (FormulaRecordAggregate) _record;
            fr.setCachedStringResult(value.getString());
            // Update our local cache to the un-formatted version
            _stringValue = new HSSFRichTextString(value.getString());

            // All done
            return;
        

        // If we get here, we're not dealing with a formula,
        //  so handle things as a normal rich text cell

        if (_cellType != CellType.STRING) 
            setCellType(CellType.STRING, false, row, col, styleIndex);
        
        int index = 0;

        HSSFRichTextString hvalue = (HSSFRichTextString) value;
        UnicodeString str = hvalue.getUnicodeString();
        index = _book.getWorkbook().addSSTString(str);
        (( LabelSSTRecord ) _record).setSSTIndex(index);
        _stringValue = hvalue;
        _stringValue.setWorkbookReferences(_book.getWorkbook(), (( LabelSSTRecord ) _record));
        _stringValue.setUnicodeString(_book.getWorkbook().getSSTString(index));
    

解决方法

在网上搜索，整理一下两种处理方法：

• 复制org.apache.poi.ss.SpreadsheetVersion代码到项目里，包路径这些不能修改，然后找到EXCEL2007(0x100000, 0x4000, 255, Integer.MAX_VALUE, 64000, 32767);，修改最后面的值，可以修改为Integer.MAX_VALUE
  
• 通过反射机制修改

public static void resetCellMaxTextLength() 
    SpreadsheetVersion excel2007 = SpreadsheetVersion.EXCEL2007;
    if (Integer.MAX_VALUE != excel2007.getMaxTextLength()) 
        Field field;
        try 
        	// SpreadsheetVersion.EXCEL2007的_maxTextLength变量 
            field = excel2007.getClass().getDeclaredField("_maxTextLength");
            // 关闭反射机制的安全检查，可以提高性能
            field.setAccessible(true);
            // 重新设置这个变量属性值
            field.set(excel2007,Integer.MAX_VALUE);
         catch (Exception e) 
            e.printStackTrace();
        
    

参考资料

• https://www.jianshu.com/p/9e73399b6c38
• https://blog.csdn.net/yandype/article/details/122718307