使用比较器按索引对 List<String[]> 进行排序

Question

我有一个 CSV 文件，我需要按两列对内容进行排序。第一列是日期，第四列是文本。我需要按第一列和第四列排序的文件。我正在尝试这样：

//i read file and iterate in lines
PriorityQueue<String[]> linesOrdenered = new PriorityQueue<>(new LineComparator());
while ((line = br.readLine()) != null) {
                String[] row = line.split(CVS_SPLIT_BY);
                if ((!isHeader) && row[0].equals("Route Date")) {
                    header = line;
                    isHeader = true;
                    continue;
                }
                linesOrdenered.add(row);
            }


public class LineComparator implements Comparator<String[]> {
        //string[3] == key
        @Override
        public int compare(String[] strings, String[] t1) {
            int keyComparator = 0;
            try {
                Date dataOne = format.parse(strings[0]);
                Date dataTwo = format.parse(t1[0]);
                keyComparator = dataOne.compareTo(dataTwo);
            } catch (ParseException e) {
                LOGGER.error("Error on parse Data [{}]", e.getMessage());
            }
            if (keyComparator == 0) {
                keyComparator = strings[3].compareTo(t1[3]);
            }
            return keyComparator;
        }

    }

结果是一个只排序日期的 PriorityQueue。 CSV 文件的示例内容：

12/01/2018,6:30,C-993BNT,A1001
12/03/2018,6:30,C-993BNT,A1001
12/04/2018,6:30,C-993BNT,A1001
12/05/2018,6:30,C-993BNT,A1001
12/01/2018,6:30,C-555BQJ,A1003
12/03/2018,6:30,C-555BQJ,A1003
12/04/2018,6:30,C-555BQJ,A1003
12/05/2018,6:30,C-555BQJ,A1003
12/06/2018,6:30,C-555BQJ,A1003
12/07/2018,6:30,C-555BQJ,A1003

Answer 1

您的输入文件和 "format" 对我们不可用，但我有根据的猜测是使用格式解析时所有日期都不同（至少在比较它们的范围内 return 0).

Answer 2

继续 Roy Shahaf 的想法，假设：

private static DateFormat format = new SimpleDateFormat("MM/dd/yyyy");

我得到：

12/01/2018,6:30,C-993BNT,A1001
12/01/2018,6:30,C-555BQJ,A1003
12/03/2018,6:30,C-993BNT,A1001
12/03/2018,6:30,C-555BQJ,A1003
12/04/2018,6:30,C-993BNT,A1001
12/04/2018,6:30,C-555BQJ,A1003
12/05/2018,6:30,C-993BNT,A1001
12/05/2018,6:30,C-555BQJ,A1003
12/06/2018,6:30,C-555BQJ,A1003
12/07/2018,6:30,C-555BQJ,A1003

我觉得很合适。见 https://jdoodle.com/a/QXP

使用比较器按索引对 List<String[]> 进行排序

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