java - 使用java在Excel工作表中的列之间交换

Question

我是java新手。实际上我想使用java交换Excel工作表中的两列。我使用了代码，但没有得到正确的输出。我添加了 Excel 工作表的屏幕截图。我想交换系统名称和日期列。

我还添加了错误输出的屏幕截图。我得到的是 1900 年 1 月 24 日和 29 日，而不是 2016 年 9 月 1 日至 30 日。

CellStyle cellStyle1 = workbook11.createCellStyle();
CreationHelper createHelper1 = workbook11.getCreationHelper();
cellStyle1.setDataFormat(createHelper1.createDataFormat().getFormat("d-mmm"));
try {
    if (file11.exists()) {
        String dt = sh1.getRow(0).getCell(1).getStringCellValue();
        if (!dt.equalsIgnoreCase("Date")) {
            Iterator<Row> rowIterator1 = sh1.iterator();
            while (rowIterator1.hasNext()) {
                Row row = rowIterator1.next();
                if (row.getCell(1).getStringCellValue().equalsIgnoreCase("Date")) {
                    Cell cl1 = row.getCell(0);
                    Cell cl2 = row.getCell(1);
                    Cell temp = row.getCell(0);
                    Cell temp1 = row.getCell(1);
                    cl1.setCellValue(temp1.getStringCellValue());
                    cl2.setCellValue(temp.getStringCellValue());
                } else {
                    Cell cl1 = row.getCell(0);
                    Cell cl2 = row.getCell(1);
                    cl2.setCellType(Cell.CELL_TYPE_STRING);
                    cl1.setCellType(Cell.CELL_TYPE_STRING);
                    Cell temp = row.getCell(0);
                    Cell temp1 = row.getCell(1);
                    cl1.setCellValue(temp1.getStringCellValue());
                    cl2.setCellValue(temp.getStringCellValue());
                    row.getCell(1).setCellStyle(cellStyle1);
                }
            }
        }
    }
}

编辑:
根据xenteros的回答我尝试了以下方法:

         CellStyle cellStyle1 = workbook11.createCellStyle();
         CreationHelper createHelper1 = workbook11.getCreationHelper();
         cellStyle1.setDataFormat(createHelper1.createDataFormat().getFormat("d-mmm"));
          try {
                if (file11.exists()) {

                  String dt = sh1.getRow(0).getCell(1).getStringCellValue();
                  if (!dt.equalsIgnoreCase("Date")) {
                  Iterator<Row> rowIterator1 = sh1.iterator();
                  while (rowIterator1.hasNext()) {
                  Row row = rowIterator1.next();
                 if (row.getCell(1).getStringCellValue().equalsIgnoreCase("Date")) {
                 Cell cl1 = row.getCell(0);
                 Cell cl2 = row.getCell(1);
                 String temp = new String(cl2.getStringCellValue());
                 cl2.setCellValue(cl1.getStringCellValue());
                 cl1.setCellValue(temp);
          else {

                   Cell cl1 = row.getCell(0);
                   Cell cl2 = row.getCell(1);
                   cl2.setCellType(Cell.CELL_TYPE_STRING);
                   cl1.setCellType(Cell.CELL_TYPE_STRING);
                   String temp = new String(cl2.getStringCellValue());
                   System.out.println(temp);
                   java.util.Date temp2 = cl1.getDateCellValue();
                   cl2.setCellStyle(cellStyle1);
                   cl2.setCellValue(temp2);
                   cl1.setCellType(Cell.CELL_TYPE_STRING);
                   cl1.setCellValue(temp);
           }
}

Answer 1

你的问题基本上是关于java引用或关于交换算法。

Memory:
+-------------+--------------------+--------+--------+
|   cell 1    |       cell 2       | cell 3 | cell 4 |
+-------------+--------------------+--------+--------+
| ["Date"...] | ["System name"...] |        |        |
+-------------+--------------------+--------+--------+

References before step 5:
+--------+-------+-------+-------+
|  cl1   |  cl2  | temp  | temp1 |
+--------+-------+-------+-------+
| cell 1 | cell2 | cell1 | cell2 |
+--------+-------+-------+-------+

Memory after step 5:
+--------------------+--------------------+--------+--------+
|       cell 1       |       cell 2       | cell 3 | cell 4 |
+--------------------+--------------------+--------+--------+
| ["System name"...] | ["System name"...] |        |        |
+--------------------+--------------------+--------+--------+
References after step 5:
+--------+-------+-------+-------+
|  cl1   |  cl2  | temp  | temp1 |
+--------+-------+-------+-------+
| cell 1 | cell2 | cell1 | cell2 |
+--------+-------+-------+-------+


1. Cell cl1 = row.getCell(0);
2. Cell cl2 = row.getCell(1);
3. Cell temp = row.getCell(0);
4. Cell temp1 = row.getCell(1);
5. cl1.setCellValue(temp1.getStringCellValue());
6. cl2.setCellValue(temp.getStringCellValue());

所以...第 6 步将 cl2 cellValue 设置为 temp(数据位于 cell1 中)的值，该值此时为“系统名称”。

下面的内容可以工作，但没有必要。

1. Cell cl1 = row.getCell(0);
2. Cell cl2 = row.getCell(1);
3. String temp1 = new String(cl1.getStringCellValue());
4. String temp2 = new String(cl2.getStringCellValue());
5. cl1.setCellValue(temp2);
6. cl2.setCellValue(temp1);

您想要做的是交换单元格的内容。无需自行交换单元。看看你能做什么:

1. Cell cl0 = row.getCell(0);
2. Cell cl1 = row.getCell(1);
3. String temp = new String(cl1.getStringValue());
4. cl1.setStringValue(cl0.getStringValue());
5. cl0.setStringValue(temp);


1. Cell cl0 = row.getCell(0);
2. Cell cl1 = row.getCell(1);
3. String temp = new String(cl1.getStringValue());
4. java.util.Date temp2 = cl0.getDateValue();
5. cl1.setCellStyle(cellStyle1);
6. cl1.setCellValue(temp2);
7. cl0.setCellType(Cell.CELL_TYPE_STRING);
8. cl0.setCellValue(temp);

编辑:

由于OP非常难，我将整个代码粘贴到这里。

try {
    if (file11.exists()) {
        String dt = sh1.getRow(0).getCell(1).getStringCellValue();
        if (!dt.equalsIgnoreCase("Date")) {
            Iterator<Row> rowIterator1 = sh1.iterator();
            while (rowIterator1.hasNext()) {
                Row row = rowIterator1.next();
                if (row.getCell(1).getStringCellValue().equalsIgnoreCase("Date")) {
                    Cell cl0 = row.getCell(0);
                    Cell cl1 = row.getCell(1);
                    String temp = new String(cl1.getStringValue());
                    cl1.setStringValue(cl0.getStringValue());
                    cl0.setStringValue(temp);
                } else {
                    Cell cl0 = row.getCell(0);
                    Cell cl1 = row.getCell(1);
                    String temp = new String(cl1.getStringValue());
                    java.util.Date temp2 = cl0.getDateValue();
                    cl1.setCellStyle(cellStyle1);
                    cl1.setCellValue(temp2);
                    cl0.setCellType(Cell.CELL_TYPE_STRING);
                    cl0.setCellValue(temp);
                }
            }
        }
    }
}