package cn.com.hmsm.bif.xingwen.accounting;  
  
import com.alibaba.excel.metadata.Head;  
import com.alibaba.excel.write.merge.AbstractMergeStrategy;  
import lombok.extern.slf4j.Slf4j;  
import org.apache.poi.ss.usermodel.Cell;  
import org.apache.poi.ss.usermodel.Row;  
import org.apache.poi.ss.usermodel.Sheet;  
import org.apache.poi.ss.util.CellRangeAddress;  
  
import java.util.List;  
  
/**  
 * 指定列，如果相鄰兩行的數(shù)據(jù)相同，則合并為一行  
 */  
@Slf4j  
public class ColumnSameDataMergeStrategy extends AbstractMergeStrategy {  
  
    private final int mergeRowIndex;  
  
    public ColumnSameDataMergeStrategy(int mergeRowIndex) {  
        this.mergeRowIndex = mergeRowIndex;  
    }  
  
    @Override  
    protected void merge(  
            Sheet sheet,  
            Cell cell,  
            Head head,  
            Integer relativeRowIndex  
    ) {  
  
        int rowIndex = cell.getRowIndex();  
        int colIndex = cell.getColumnIndex();  
  
        // 必須這樣使用，不然lastRow 永遠(yuǎn)為空  
        sheet = cell.getSheet();  
        Row lastRow = sheet.getRow(rowIndex - 1);  
        if (lastRow == null) {  
            log.warn("rowIndex is {}, lastRow is null , data is {} ", rowIndex, cell);  
            return;  
        }  
        Cell lastRowCell = lastRow.getCell(colIndex);  
        // 先進(jìn)行列的判斷，再進(jìn)行的判斷  
        if (colIndex != mergeRowIndex) {  
            return;  
        }  
//        log.info("rowIndex is {}, data is {}", rowIndex, cell.toString());  
  
        // 如果數(shù)據(jù)相同，才進(jìn)行合并  
        if (!lastRowCell.getStringCellValue().equals(cell.getStringCellValue())) {  
            return;  
        }  
  
        // 檢查當(dāng)前單元格是否已在合并中，如果在，則修改合數(shù)據(jù)；如果不存在，新建  
        List<CellRangeAddress> list = sheet.getMergedRegions();  
        for (int i = 0, listSize = list.size(); i < listSize; i++) {  
            CellRangeAddress cellAddresses = list.get(i);  
            // 檢查列是否相同  
            if (cellAddresses.getFirstColumn() != colIndex || cellAddresses.getLastColumn() != colIndex) {  
                continue;  
            }  
            // 因?yàn)閿?shù)據(jù)是從上到下添加的，行數(shù)是依次遞增的，所以只需要檢查合并的最后一行和上一行是否相同即可。  
            if (cellAddresses.getLastRow() == lastRowCell.getRowIndex()) {  
                // 見(jiàn)最后一行，改為當(dāng)前行  
                cellAddresses.setLastRow(rowIndex);  
                sheet.removeMergedRegion(i);  
                sheet.addMergedRegion(cellAddresses);  
                return;  
            }  
  
        }  
  
        // 不存在已合并的區(qū)域，新建合格合并區(qū)域  
        CellRangeAddress cra = new CellRangeAddress(lastRowCell.getRowIndex(), cell.getRowIndex(), lastRowCell.getColumnIndex(), cell.getColumnIndex());  
        sheet.addMergedRegion(cra);  
  
    }  
  
}

try (ExcelWriter excelWriter = EasyExcel.write(filePath).withTemplate(templateFileName).build()) {  
                    WriteSheet writeSheet = EasyExcel.writerSheet("對(duì)賬單")  
                                    .registerWriteHandler(new ColumnSameDataMergeStrategy(0))  
                                    .build();  
                    Map<String, Object> map = MapUtils.newHashMap();  
                    map.put("title", title);  
                    map.put("time", reconciliationCycle);  
                    excelWriter.fill(map, writeSheet);  

                    // 這里注意 入?yún)⒂昧薴orceNewRow 代表在寫(xiě)入list的時(shí)候不管list下面有沒(méi)有空行 都會(huì)創(chuàng)建一行，然后下面的數(shù)據(jù)往后移動(dòng)。默認(rèn) 是false，會(huì)直接使用下一行，如果沒(méi)有則創(chuàng)建。  
                    // forceNewRow 如果設(shè)置了true,有個(gè)缺點(diǎn) 就是他會(huì)把所有的數(shù)據(jù)都放到內(nèi)存了，所以慎用  
                    // 簡(jiǎn)單的說(shuō) 如果你的模板有l(wèi)ist,且list不是最后一行，下面還有數(shù)據(jù)需要填充 就必須設(shè)置 forceNewRow=true 但是這個(gè)就會(huì)把所有數(shù)據(jù)放到內(nèi)存 會(huì)很耗內(nèi)存  
                    FillConfig fillConfig = FillConfig.builder().forceNewRow(Boolean.TRUE).build();  
                    excelWriter.fill(byStoreDtoList, fillConfig, writeSheet);  
//                    excelWriter.fill(byStoreDtoList, writeSheet);  
            }