Bug 53877

I've also had difficulty getting a working 'deleteColumns()' method, and would very much like to know if a solution is on offer.

When I run your test-program with the latest trunk-version of poi I get A D E correctly, it seems the bug was fixed at some point. Please reopen or report a new bug with updated information if there is still a problem for you with snapshot builds or the next upcoming release (likely 3.10).

This bug recurs in 3.12.

Using the previously-attached POI_error_in_column_deletes class, I created a batch file comprising the following commands:

set c1=poi-3.12-20150511.jar
set c2=POI_error_in_column_deletes
del %c2%.class
del testDeleteColumns.xls
javac -cp %c1% %c2%.java
java -cp %c1%; %c2%

The result is a new .xls file whose columns read 'ACE', instead of the proper output of 'ADE'.

The java version running is 1.8.0_60. The POI version is 3.12-20150511.

I tried it again at it does work for me, not sure where the difference is to what you see. Please use the following unit test and show how it needs to be adjusted to cause the problem if this is really still a problem for you.

This test verifies that "A", "D", "E" end up in the columns, but I also checked with LibreOffice (sorry, no MS Office on this machine)

    private static final int ROWS = 10;
    private static final int COLS = 10;

    @Test
    public void test_deleteColumns() throws IOException {
        HSSFWorkbook wb = new HSSFWorkbook();
        HSSFSheet sh = wb.createSheet("sheet1");
        HSSFRow r = null;
        for (int row = 0; row < ROWS; row++) {
            r = sh.createRow(row);
            for (int col = 0; col < COLS; col++) {
                r.createCell(col);
            }
        }
        sh.getRow(2).getCell(0).setCellValue("A");
        sh.getRow(2).getCell(1).setCellValue("B");
        sh.getRow(2).getCell(2).setCellValue("C");
        sh.getRow(2).getCell(3).setCellValue("D");
        sh.getRow(2).getCell(4).setCellValue("E");
        // Put in ABCDE into consecutive cells;
        // deletion should have gotten ADE but got ACE instead.
        for (int deleteIndex = 0; deleteIndex < 2; deleteIndex++) {
            HSSFRow row = sh.getRow(2);
            if (null != row) {
                deleteColumnFromRow(row, 1);
            }
        }
        
        assertEquals("A", sh.getRow(2).getCell(0).getStringCellValue());
        assertEquals("D", sh.getRow(2).getCell(1).getStringCellValue());
        assertEquals("E", sh.getRow(2).getCell(2).getStringCellValue());
        
        wb.close();
    }


    private void deleteColumnFromRow(HSSFRow row, final int START_COL) {
        if (START_COL >= COLS) {
            return;
        }
        HSSFCell check = row.getCell(START_COL);
        if (null != check) {
            row.removeCell(check);
        }
        System.err.println(
                "        deleteColumnFromRow: row = " + row.getRowNum());
        HSSFCell cell = null;
        for (int col = START_COL + 1; col < COLS; col++) {
            int source = col;
            int destination = col - 1;
            cell = row.getCell(source);
            if (null != row.getCell(destination)) {
                row.removeCell(row.getCell(destination));
                // Because the API says the destination cannot exist,
                // the destination has been deleted. The API reference is
                // poi.apache.org/apidocs/org/apache/poi/hssf/usermodel/HSSFRow.html
            }
            if (null != cell) {
                // moveCell is most likely where the error occurs.
                row.moveCell(cell, (short) (destination));
            }
        }
    }