Data imported by POI in one line and one line has many articles on the Internet, but it seems difficult to import an excel with merged cells. Just recently completed a requirement to import excel with merged cells:

 1 /**
 2      * Read excel data and call this method to start
 3      * @param is
 4      * @param indexNum At least how many columns of data are required
 5      */
 6     public static List<Object[]> readExcelToObj(InputStream is,int indexNum) {
 7 
 8         Workbook wb = null;
 9         List<Object[]> objArrList = null;
10         try {
11             objArrList = new ArrayList<>();
12             wb = WorkbookFactory.create(is);
13             readExcel(wb, 0, 0, 0,objArrList,indexNum);
14         } catch (InvalidFormatException e) {
15             e.printStackTrace();
16         } catch (IOException e) {
17             e.printStackTrace();
18         }
19         return objArrList;
20     }

 1 /**
 2      * Read excel file
 3      * @param wb
 4      * @param sheetIndex sheet Page Subscription: Starting from 0
 5      * @param startReadLine Start reading rows: start at 0
 6      * @param tailLine Remove the last read line
 7      */
 8     public static void readExcel(Workbook wb,int sheetIndex, int startReadLine, int tailLine, List<Object[]> objArrList, int indexNum) {
 9         Sheet sheet = wb.getSheetAt(sheetIndex);
10         Row row = null;
11 
12         for(int i=startReadLine; i<sheet.getLastRowNum()-tailLine+1; i++) {
13             row = sheet.getRow(i);
14             List<Object> objList = new ArrayList<>();
15             for(int j = 0 ; j<row.getLastCellNum();j++) {
16                 //for(Cell c : row) {
17                 Cell c = row.getCell(j);
18                 if(c==null){
19                     objList.add("");
20                     continue;
21                 }
22                 boolean isMerge = isMergedRegion(sheet, i, c.getColumnIndex());
23 　　　　　　　　　　//Determine whether a merged cell exists
24                 if(isMerge) {
25                     String rs = getMergedRegionValue(sheet, row.getRowNum(), c.getColumnIndex());
26                     objList.add(rs);
27                 }else {
28                     objList.add(getCellValue(c));
29                 }
30 
31             }
32             while(objList.size()<indexNum){
33                 objList.add("");
34             }
35             objArrList.add(objList.toArray());
36         }
37     }

 1 /**
 2      * Get the value of the merged cell
 3      * @param sheet
 4      * @param row
 5      * @param column
 6      * @return
 7      */
 8     public static String getMergedRegionValue(Sheet sheet ,int row , int column){
 9         int sheetMergeCount = sheet.getNumMergedRegions();
10 
11         for(int i = 0 ; i < sheetMergeCount ; i++){
12             CellRangeAddress ca = sheet.getMergedRegion(i);
13             int firstColumn = ca.getFirstColumn();
14             int lastColumn = ca.getLastColumn();
15             int firstRow = ca.getFirstRow();
16             int lastRow = ca.getLastRow();
17 
18             if(row >= firstRow && row <= lastRow){
19 
20                 if(column >= firstColumn && column <= lastColumn){
21                     Row fRow = sheet.getRow(firstRow);
22                     Cell fCell = fRow.getCell(firstColumn);
23                     return getCellValue(fCell) ;
24                 }
25             }
26         }
27 
28         return null ;
29     }

 1 /**
 2      * Determine whether the specified cell is a merged cell or not?
 3      * @param sheet
 4      * @param row row subscript
 5      * @param column column subscript
 6      * @return
 7      */
 8     public static boolean isMergedRegion(Sheet sheet,int row ,int column) {
 9         int sheetMergeCount = sheet.getNumMergedRegions();
10         for (int i = 0; i < sheetMergeCount; i++) {
11             CellRangeAddress range = sheet.getMergedRegion(i);
12             int firstColumn = range.getFirstColumn();
13             int lastColumn = range.getLastColumn();
14             int firstRow = range.getFirstRow();
15             int lastRow = range.getLastRow();
16             if(row >= firstRow && row <= lastRow){
17                 if(column >= firstColumn && column <= lastColumn){
18                     return true;
19                 }
20             }
21         }
22         return false;
23     }

 1 /**
 2      * Get the value of the cell
 3      * @param cell
 4      * @return
 5      */
 6     public static String getCellValue(Cell cell){
 7 
 8         if(cell == null) return "";
 9 
10         if(cell.getCellType() == Cell.CELL_TYPE_STRING){
11 
12             return cell.getStringCellValue();
13 
14         }else if(cell.getCellType() == Cell.CELL_TYPE_BOOLEAN){
15 
16             return String.valueOf(cell.getBooleanCellValue());
17 
18         }else if(cell.getCellType() == Cell.CELL_TYPE_FORMULA){
19 
20             return cell.getCellFormula() ;
21 
22         }else if(cell.getCellType() == Cell.CELL_TYPE_NUMERIC){
23 
24             return String.valueOf(cell.getNumericCellValue());
25 
26         }
27         return "";
28     }

Note: This import function is also suitable for single-line reading, just call readExcel ToObj () method directly; parameter 1: input stream into excel file; parameter 2: specify how many columns of data you want to read at least (e.g. input 0, which means: if you have only three columns of data in all rows, the length of the array you get is only 3; if you pass in 10, those are only 3 columns. Three columns of data will automatically fill empty strings into the array, so that the minimum length of each array is 10;