Making a List in Java from a text file

Question

In Java I'm using the Scanner to read from a text file, for example (cat, dog, mouse). When I use the System.out.println() the output appears like cat, dog, mouse

I want the list to look like this

cat
dog
mouse

any help code below

    Scanner scan = null;
    Scanner scan2 = null;
    boolean same = true;
    try {
        scan = new Scanner(new      
        File("//home//mearts//keywords.txt"));
    } catch (FileNotFoundException e)
    {
        e.printStackTrace();
    }
    List<String> firstLines = new ArrayList<String>();
    while (scan.hasNextLine()) {
    firstLines.add(scan.nextLine());
    System.out.println(firstLines);
}

There is a similar answer here: http://stackoverflow.com/questions/5343689/java-reading-a-file-into-an-arraylist — djangofan, Dec 06 '16 at 21:11

Roland · Answer 1 · 2016-12-06T21:50:12.320

2

Try something like:

firstLines.forEach(System.out::println);

By the way, as you are only reading lines, you may also want to have a look at java.nio.file.Files:

Path keywordsFilepath = Paths.get(/* your path */...);
Files.lines(keywordsFilepath)
     .forEach(System.out::println);

edited Dec 06 '16 at 21:50

answered Dec 06 '16 at 21:12

Roland

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score 2 · Answer 2 · answered Dec 06 '16 at 21:16

You are reading the file line by line, instead of taking the delimiters into consideration:

try (Scanner scan = 
     new Scanner("//home//mearts//keywords.txt").useDelimiter(", ")) {
    while (scan.hasNext()) {
        System.out.println(scan.next());
    }
} catch (FileNotFoundException e) {
    e.printStackTrace(); // Or something more useful
}

Making a List in Java from a text file

2 Answers2