将While循环更改为for循环

时间:2018-03-05 12:15:24

标签: java for-loop foreach while-loop apache-poi

你好这里的人在这个extractTable方法中使用while(true)。根据方法,如果条件失败,它将是一个无限循环,这是一个糟糕的编程实践,你可以帮助我改变,为每个或每个

private List<Map<String, Map<String, Integer>>> extractTable(XSSFSheet sheet, Cell tablePosition) {
    List<Map<String, Map<String, Integer>>> table = new ArrayList<>();

    int headerRow = tablePosition.getRowIndex();
    int valuesHeaderColumn = tablePosition.getColumnIndex();

    // read all columns and rows until finding an empty one
    int row = headerRow + 1;
    int col = valuesHeaderColumn + 1;

    // read all columns starting at col
    while (true) {
        Map<String, Map<String, Integer>> tableColumn = new HashMap<>();
        Cell headerCell = sheet.getRow(headerRow).getCell(col);
        if (headerCell == null)
            break;
        String columnName = headerCell.getStringCellValue().toUpperCase();
        if ("".equals(columnName))
            break;

        // read all rows starting at row
        Map<String, Integer> values = new HashMap<>();
        while (true) {
            Row valueHeaderRow = sheet.getRow(row);
            if (valueHeaderRow == null)
                break;
            Cell valueHeaderCell = valueHeaderRow.getCell(valuesHeaderColumn);
            String valueHeader = valueHeaderCell.getStringCellValue();
            if ("".equals(valueHeader))
                break;
            Cell valueCell = sheet.getRow(row).getCell(col);
            Integer value = (int) valueCell.getNumericCellValue();
            values.put(valueHeader, value);
            row++;
        }

        tableColumn.put(columnName, values);
        // Add the columns map to the list
        table.add(tableColumn);
        col++;
        row = headerRow + 1;
    }
    return table;
}

1 个答案:

答案 0 :(得分:1)

我不相信(真的)......休息是一种糟糕的编程习惯,看here。但是要使用POI迭代电子表格的行和列,你可以这样做recommended

for (Row row: sheet) {
  for (Cell cell: row) {
    // do something here
  }
}