Question

我正在尝试删除时间表中的alle 30 Min字样。目前正在删除30和Min，但不会删除alle字样。我该如何解决这个问题？

我感谢任何帮助。

示例

apple 05:05 05:35 06:05 06:35 07:05 07:35 08:05 17:05 17:35 18:05 18:35 19:05 19:35
chairalle 05:08 05:38 06:09 06:39 07:09 07:39 08:09 17:09 17:39 18:09 18:39 19:09 19:39
tablealle 05:09 05:39 06:11 06:41 07:11 07:41 08:11 alle 17:11 17:41 18:11 18:41 19:11 19:41
spoonalle 05:11 05:41 06:14 06:44 07:14 30 07:44 08:14  17:14 17:44 18:14 18:44 19:14 19:44
cabelalle 05:13 05:43 06:17 06:47 07:17 07:47 08:17 17:17 17:47 Min 18:17 18:47 19:17 19:47

没有延迟的最终输出30分钟

apple 05:05 05:35 06:05 06:35 07:05 07:35 08:05 17:05 17:35 18:05 18:35 19:05 19:35
chairalle 05:08 05:38 06:09 06:39 07:09 07:39 08:09 17:09 17:39 18:09 18:39 19:09 19:39
tablealle 05:09 05:39 06:11 06:41 07:11 07:41 08:11 17:11 17:41 18:11 18:41 19:11 19:41
spoonalle 05:11 05:41 06:14 06:44 07:14 07:44 08:14  17:14 17:44 18:14 18:44 19:14 19:44
cabelalle 05:13 05:43 06:17 06:47 07:17 07:47 08:17 17:17 17:47 18:17 18:47 19:17 19:47

代码：

    Scanner scannerLines = new Scanner(file)) {

    while (scannerLines.hasNextLine()) {
        String line = scannerLines.nextLine();
        if (line.contains(" alle ")) {
            //Delete alle from the line.
            line.replace(" alle ", " ");
            String nextLine = scannerLines.nextLine();
            Pattern pattern = Pattern.compile("\\s\\d\\d\\s");

            Matcher m = pattern.matcher(nextLine);
            while (m.find()) {
                value = Integer.parseInt(m.group().trim());
                line.replace(m.group(), " ");

                String nextLine2 = scannerLines.nextLine();
                nextLine2.replace("Min", " ");
                System.out.println(value);
            }
        }
        writer.println(line);
    }

Answer 1

将结果字符串分配回行！

line = line.replace(" alle ", " ");

请参阅String#replace

工作示例：

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;

public class TestReplace {

    public static void main (String [] args) {

        File inputFile = new File("Input.txt");
        File outputFile = new File("Output.txt");

        Scanner sc = null;
        FileWriter fw = null;

        try {       
            sc = new Scanner(inputFile);
            fw = new FileWriter(outputFile);

            while(sc.hasNextLine()) {
                String str = sc.nextLine();                 
                str = str.replaceAll("\\s30\\s|\\salle\\s|\\sMin\\s", " ");                 
                fw.write(str + "\r\n");
            }

            sc.close();
            fw.close();

        } catch (FileNotFoundException e2) {
            e2.printStackTrace();
        } catch (IOException e1) {
            e1.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

<强>输出：

apple 05:05 05:35 06:05 06:35 07:05 07:35 08:05 17:05 17:35 18:05 18:35 19:05 19:35
chairalle 05:08 05:38 06:09 06:39 07:09 07:39 08:09 17:09 17:39 18:09 18:39 19:09 19:39
tablealle 05:09 05:39 06:11 06:41 07:11 07:41 08:11 17:11 17:41 18:11 18:41 19:11 19:41
spoonalle 05:11 05:41 06:14 06:44 07:14 07:44 08:14  17:14 17:44 18:14 18:44 19:14 19:44
cabelalle 05:13 05:43 06:17 06:47 07:17 07:47 08:17 17:17 17:47 18:17 18:47 19:17 19:47

Answer 2

你在单词alle之前和之后都有空格，所以删除它。

line.replace("alle", " ");

Answer 3

replace(...)方法无法修改原始String，它会返回新修改的String。你需要做这样的事情：

line = line.replace(" alle ", " ");

这是一个完整的解决方案：

Scanner scannerLines = new Scanner(file);
boolean alleFound = false;
boolean nrFound = false;
boolean minFound = false;
while (scannerLines.hasNextLine()) {
    String line = scannerLines.nextLine();
    if (!alleFound && line.contains(" alle ")) {
        line = line.replace(" alle ", " ");
        alleFound = true;
    } else if (alleFound && !nrFound) {
        line = line.replaceFirst("\\s\\d\\d\\s", " ");
        nrFound = true;
    } else if (alleFound && nrFound && !minFound) {
        line = line.replace("Min", " ");
        minFound = true;
    }
    writer.println(line);
}

从文本文件中的一行中删除单词

3 个答案: