POI-java讀取Excel(包含合併單元格)

import org.apache.poi.hssf.usermodel.HSSFWorkbook;
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.ss.util.CellRangeAddress;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;


public class ExcelImportServiceImpl {


    @Override
    public String importExcel(InputStream inputStream, String fileName) throws Exception{

        String message = "Import success";

        boolean isE2007 = false;
        //判斷是不是excel2007格式
        if(fileName.endsWith("xlsx")){
            isE2007 = true;
        }

        int rowIndex = 0;
        try {
            InputStream input = inputStream;  //創建輸入流
            Workbook wb;
            //根據文件格式(2003或者2007)來初始化
            if(isE2007){
                wb = new XSSFWorkbook(input);
            }else{
                wb = new HSSFWorkbook(input);
            }
            Sheet sheet = wb.getSheetAt(0);    //得到第一個表單
            int rowCount = sheet.getLastRowNum()+1;

            for(int i = 1; i < rowCount;i++){
                rowIndex = i;
                Row row ;

                for(int j = 0;j<26;j++){
                    if(isMergedRegion(sheet,i,j)){
                        System.out.print(getMergedRegionValue(sheet,i,j)+"\t");
                    }else{
                        row = sheet.getRow(i);
                        System.out.print(row.getCell(j)+"\t");
                    }
                }
                System.out.print("\n");
            }
        } catch (Exception ex) {
            message =  "Import failed, please check the data in "+rowIndex+" rows ";
        }
        return message;
    }


    /**
     * 獲取單元格的值
     * @param cell
     * @return
     */
    public  String getCellValue(Cell cell){
        if(cell == null) return "";
        return cell.getStringCellValue();
    }


    /**
     * 合併單元格處理,獲取合併行
     * @param sheet
     * @return List<CellRangeAddress>
     */
    public  List<CellRangeAddress> getCombineCell(Sheet sheet)
    {
        List<CellRangeAddress> list = new ArrayList<>();
        //得到一個 sheet 中合併單元格的數量
        int sheetmergerCount = sheet.getNumMergedRegions();
        //遍歷全部的合併單元格
        for(int i = 0; i<sheetmergerCount;i++)
        {
            //得到合併單元格保存進list中
            CellRangeAddress ca = sheet.getMergedRegion(i);
            list.add(ca);
        }
        return list;
    }

    private  int getRowNum(List<CellRangeAddress> listCombineCell,Cell cell,Sheet sheet){
        int xr = 0;
        int firstC = 0;
        int lastC = 0;
        int firstR = 0;
        int lastR = 0;
        for(CellRangeAddress ca:listCombineCell)
        {
            //得到合併單元格的起始行, 結束行, 起始列, 結束列
            firstC = ca.getFirstColumn();
            lastC = ca.getLastColumn();
            firstR = ca.getFirstRow();
            lastR = ca.getLastRow();
            if(cell.getRowIndex() >= firstR && cell.getRowIndex() <= lastR)
            {
                if(cell.getColumnIndex() >= firstC && cell.getColumnIndex() <= lastC)
                {
                    xr = lastR;
                }
            }

        }
        return xr;

    }
    /**
     * 判斷單元格是否爲合併單元格，是的話則將單元格的值返回
     * @param listCombineCell 存放合併單元格的list
     * @param cell 須要判斷的單元格
     * @param sheet sheet
     * @return
     */
    public  String isCombineCell(List<CellRangeAddress> listCombineCell,Cell cell,Sheet sheet)
            throws Exception{
        int firstC = 0;
        int lastC = 0;
        int firstR = 0;
        int lastR = 0;
        String cellValue = null;
        for(CellRangeAddress ca:listCombineCell)
        {
            //得到合併單元格的起始行, 結束行, 起始列, 結束列
            firstC = ca.getFirstColumn();
            lastC = ca.getLastColumn();
            firstR = ca.getFirstRow();
            lastR = ca.getLastRow();
            if(cell.getRowIndex() >= firstR && cell.getRowIndex() <= lastR)
            {
                if(cell.getColumnIndex() >= firstC && cell.getColumnIndex() <= lastC)
                {
                    Row fRow = sheet.getRow(firstR);
                    Cell fCell = fRow.getCell(firstC);
                    cellValue = getCellValue(fCell);
                    break;
                }
            }
            else
            {
                cellValue = "";
            }
        }
        return cellValue;
    }

    /**
     * 獲取合併單元格的值
     * @param sheet
     * @param row
     * @param column
     * @return
     */
    public  String getMergedRegionValue(Sheet sheet ,int row , int column){
        int sheetMergeCount = sheet.getNumMergedRegions();

        for(int i = 0 ; i < sheetMergeCount ; i++){
            CellRangeAddress ca = sheet.getMergedRegion(i);
            int firstColumn = ca.getFirstColumn();
            int lastColumn = ca.getLastColumn();
            int firstRow = ca.getFirstRow();
            int lastRow = ca.getLastRow();

            if(row >= firstRow && row <= lastRow){
                if(column >= firstColumn && column <= lastColumn){
                    Row fRow = sheet.getRow(firstRow);
                    Cell fCell = fRow.getCell(firstColumn);
                    return getCellValue(fCell) ;
                }
            }
        }

        return null ;
    }


    /**
     * 判斷指定的單元格是不是合併單元格
     * @param sheet
     * @param row 行下標
     * @param column 列下標
     * @return
     */
    private  boolean isMergedRegion(Sheet sheet,int row ,int column) {
        int sheetMergeCount = sheet.getNumMergedRegions();
        for (int i = 0; i < sheetMergeCount; i++) {
            CellRangeAddress range = sheet.getMergedRegion(i);
            int firstColumn = range.getFirstColumn();
            int lastColumn = range.getLastColumn();
            int firstRow = range.getFirstRow();
            int lastRow = range.getLastRow();
            if(row >= firstRow && row <= lastRow){
                if(column >= firstColumn && column <= lastColumn){
                    return true;
                }
            }
        }
        return false;
    }
    
}