java excel多个sheet页_java实现excel的多sheet页合并成一个sheet，完美保证格式。可以实现合并时去掉sheet页的表头，同时设置各个sheet之间的间隔，以及递归合并...

在Java中，可以使用Apache POI库来操作Excel文件。要将多个sheet页合并成一个sheet，可以使用以下步骤：

1. 创建一个新的工作簿和工作表来存储合并后的数据。

Workbook mergedWorkbook = new XSSFWorkbook();
Sheet mergedSheet = mergedWorkbook.createSheet("Merged Data");

2. 遍历所有要合并的sheet页，并将它们的数据复制到新的工作表中。

for (int i = 0; i < sheetCount; i++) {
    Sheet sheet = workbook.getSheetAt(i);
    int rowCount = sheet.getLastRowNum();
    for (int j = 0; j <= rowCount; j++) {
        Row row = sheet.getRow(j);
        Row mergedRow = mergedSheet.createRow(mergedSheet.getLastRowNum() + 1);
        int cellCount = row.getLastCellNum();
        for (int k = 0; k < cellCount; k++) {
            Cell cell = row.getCell(k);
            Cell mergedCell = mergedRow.createCell(k);
            mergedCell.setCellValue(cell.getStringCellValue());
        }
    }
}

3. 如果需要去掉sheet页的表头，可以在循环中添加一个条件判断。

for (int j = 0; j <= rowCount; j++) {
    if (j == 0 && removeHeader) {
        continue;
    }
    //...
}

4. 如果需要设置各个sheet之间的间隔，可以在每个sheet页的末尾添加一些空行。

for (int j = 0; j < spaceBetweenSheets; j++) {
    mergedSheet.createRow(mergedSheet.getLastRowNum() + 1);
}

5. 如果需要递归合并，可以将上述步骤封装成一个方法，再在方法中递归调用自身。

public static void mergeSheets(List<File> files, int start, int end,
        boolean removeHeader, int spaceBetweenSheets, Workbook mergedWorkbook,
        Sheet mergedSheet) throws IOException {
    //...
    mergeSheets(files, i + 1, end, removeHeader, spaceBetweenSheets,
            mergedWorkbook, mergedSheet);
}

完整的代码示例如下：

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.List;
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.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class ExcelMerger {
    public static void main(String[] args) throws IOException {
        List<File> files = //...要合并的文件列表
        int spaceBetweenSheets = 2;
        boolean removeHeader = true;
        Workbook mergedWorkbook = new XSSFWorkbook();
        Sheet mergedSheet = mergedWorkbook.createSheet("Merged Data");
        mergeSheets(files, 0, files.size() - 1, removeHeader, spaceBetweenSheets,
                mergedWorkbook, mergedSheet);
        //...保存合并后的文件
    }

    public static void mergeSheets(List<File> files, int start, int end,
            boolean removeHeader, int spaceBetweenSheets, Workbook mergedWorkbook,
            Sheet mergedSheet) throws IOException {
        if (start > end) {
            return;
        }
        File file = files.get(start);
        FileInputStream inputStream = new FileInputStream(file);
        Workbook workbook = new XSSFWorkbook(inputStream);
        int sheetCount = workbook.getNumberOfSheets();
        for (int i = 0; i < sheetCount; i++) {
            Sheet sheet = workbook.getSheetAt(i);
            int rowCount = sheet.getLastRowNum();
            for (int j = 0; j <= rowCount; j++) {
                if (j == 0 && removeHeader) {
                    continue;
                }
                Row row = sheet.getRow(j);
                Row mergedRow = mergedSheet.createRow(mergedSheet.getLastRowNum() + 1);
                int cellCount = row.getLastCellNum();
                for (int k = 0; k < cellCount; k++) {
                    Cell cell = row.getCell(k);
                    Cell mergedCell = mergedRow.createCell(k);
                    mergedCell.setCellValue(cell.getStringCellValue());
                }
            }
            for (int j = 0; j < spaceBetweenSheets; j++) {
                mergedSheet.createRow(mergedSheet.getLastRowNum() + 1);
            }
        }
        inputStream.close();
        mergeSheets(files, start + 1, end, removeHeader, spaceBetweenSheets,
                mergedWorkbook, mergedSheet);
    }
}