java - 如果检测到分隔符，则在行尾添加空格？

Question

我创建了一个方法，允许我读取文本文件并将各个单词放入其自己的元素中，并用 | 分隔。

示例:

0 | john | smith | potato |

上面的内容会变成:

0
john
smith
potato

如果检测到 |，有没有办法在行尾添加空格 ()？我希望以这种方式完成，这样我就可以实现这一目标:

0
john
smith
potato
<-- empty spot goes here -->

这是我到目前为止所拥有的:

public static String[] read() throws IOException {
    String str = null;
    List<String> list = new ArrayList<String>();
    BufferedReader in = new BufferedReader(new FileReader("test.txt"));
    while ((str = in.readLine()) != null) {
        for (String token : str.split("\\|")) {
            list.add(token);
        }
    }
}

Answer 1

String.split 作为修剪前导空单元格的奇怪习惯，所以如果您有

potato||

结果将是

[potato]

但是您可以告诉不要使用 split("\\|", -1) 来修剪它。这将导致

[potato,,] //3 cells

阅读doc of Split了解更多。这是限制解释:

The limit parameter controls the number of times the pattern is applied and therefore affects the length of the resulting array. If the limit n is greater than zero then the pattern will be applied at most n - 1 times, the array's length will be no greater than n, and the array's last entry will contain all input beyond the last matched delimiter. If n is non-positive then the pattern will be applied as many times as possible and the array can have any length. If n is zero then the pattern will be applied as many times as possible, the array can have any length, and trailing empty strings will be discarded.