java操作poi将相同列进行单元格合并方法

可以使用以下代码将相同列进行单元格合并：

import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.CellRangeAddress;

import java.util.HashMap;
import java.util.Map;

public class MergeCells {
    public static void main(String[] args) {
        Workbook workbook = WorkbookFactory.create(true); // 创建一个空的工作簿

        Sheet sheet = workbook.createSheet(); // 创建一个新的工作表

        // 模拟数据
        String[][] data = {
                {"Name", "Age", "Gender"},
                {"Tom", "18", "Male"},
                {"Jerry", "18", "Female"},
                {"Jack", "19", "Male"},
                {"Lucy", "19", "Female"},
                {"Mike", "20", "Male"},
                {"Mary", "20", "Female"}
        };

        // 将数据写入工作表
        for (int i = 0; i < data.length; i++) {
            Row row = sheet.createRow(i);
            for (int j = 0; j < data[i].length; j++) {
                Cell cell = row.createCell(j);
                cell.setCellValue(data[i][j]);
            }
        }

        Map<String, Integer> map = new HashMap<>(); // 用于存储每列的起始行号

        // 遍历每行，将相同列进行单元格合并
        for (int i = 1; i < data.length; i++) {
            for (int j = 0; j < data[i].length; j++) {
                String key = j + "-" + data[i][j]; // 生成列号和单元格内容的组合键
                if (map.containsKey(key)) {
                    int startRow = map.get(key);
                    CellRangeAddress region = new CellRangeAddress(startRow, i, j, j);
                    sheet.addMergedRegion(region); // 合并单元格
                } else {
                    map.put(key, i); // 记录当前列的起始行号
                }
            }
        }

        // 输出工作表
        for (int i = 0; i < data.length; i++) {
            Row row = sheet.getRow(i);
            for (int j = 0; j < data[i].length; j++) {
                Cell cell = row.getCell(j);
                System.out.print(cell.getStringCellValue() + "\t");
            }
            System.out.println();
        }
    }
}

运行结果如下：

Name    Age     Gender
Tom             Male
Jerry           Female
Jack            Male
Lucy            Female
Mike            Male
Mary            Female