如何从txt文件读取2行

问题描述

嘿，我正在处理此问题 我想合并到txt文件的行并在Arraylist中显示它们 所以我的代码就是这样，我想跳过-在Arraylist中显示的行。

私人列表getQuotes（）{

    List<String> quotes = new ArrayList<>();

    BufferedReader bufferedReader = null;

    try {
        InputStream open = getAssets().open("barish.txt");

        bufferedReader = new BufferedReader(new InputStreamReader(open));

        String line;

        while ((line = bufferedReader.readLine()) != null) {




            quotes.add(line);
        }


    } catch (IOException e) {

        e.printstacktrace();

    } finally {

        if (bufferedReader != null) {

            try {
                bufferedReader.close();

            } catch (IOException e) {

                e.printstacktrace();
            }
        }
    }
    return quotes;
}

[在此处输入图片描述] [1]

txt文件图像在这里 [1]：https://i.stack.imgur.com/AiI67.png

解决方法

在将其添加到报价列表之前，您可以检查该行是否不等于-。

if(line.equals("--") == false) {
     quotes.add(line);
}

编辑：将各行组合在一起

为了合并-行之间的字符串，您可以将引号累加为每个-之间的字符串quoteLine。因此，如果该行不是-行，那么它将被附加到字符串quoteLine中。如果它是-行，则它将先前构造的引号添加到数组列表中，并将quoteLine初始化为空字符串以将其重置。

String line;
String quoteLine = "";
while ((line = bufferedReader.readLine()) != null) {

    if(line.equals("--") == false) {
        quotes.add(quoteLine);
        quoteLine = "";
    } else {
        quoteLine += line;
    }
 }

,

尝试使用 replaceAll 方法，然后如上所述读取文件

  line = line.replaceAll("--"," ");

//要删除所有“-”并用空格替换

,

enter image description here

这是Txt文件..

这是一个诗歌应用程序。这2行使1首诗歌 所以我想在“ Recyclerlist”视图中同时显示每两行。

这个例子...

我想在回收者视图中显示我的诗歌

enter image description here

,

您可以执行以下操作：

public static List<List<String>> getQuotes(String file) {
    List<List<String>> allQuotes = new ArrayList<>();
    try (BufferedReader br = new BufferedReader(new FileReader(file))) {

        // Let's have a queue backed by LinkedList to keep the two
        // lines just before the next line that is '--'.
        Queue<String> quotes = new LinkedList<String>();
        String line;

        while ((line = br.readLine()) != null) {

            // If the current line starts with -- and the two previous lines persisted
            // in the quotes queue to allQuotes and clear the quotes. You can do an equals
            // check here if you're certain about no leading and trailing white spaces in
            // each line and it is always --.
            if (line.trim().startsWith("--")) {

                // Don't add quotes to allQuotes when quotes queue is empty.
                // You can also check quotes.size() == 2 along with !quotes.isEmpty()
                // if you want to always have at least two quotes in each sub-list retuned.
                if (!quotes.isEmpty()) {
                    allQuotes.add(new ArrayList(quotes));
                    quotes.clear();
                }
            } else if (!line.trim().isEmpty()) {
                // Add each line into the quotes queue if it is not blank
                // or if it is not --
                quotes.add(line);
            }

            // If the size of queue is > 2 remove an item from from the front,// because we are only interested in two lines before --
            if (quotes.size() > 2) {
                quotes.remove();
            }
        }
    } catch (Exception e) {
        e.printStackTrace(); // TODO: Handle exceptions
        return null;
    }
    return allQuotes;
}

,

我想也许您想要更多这样的东西：

    public List<List<String>> getQuotes() { 
        List<List<String>> allQuotes = new ArrayList<>();
        BufferedReader bufferedReader = null;
        try {
            InputStream open = getAssets().open("barish.txt");
            bufferedReader = new BufferedReader(new InputStreamReader(open));
            String line;
            ArrayList<String> quote = new ArrayList<>();
            while ((line = bufferedReader.readLine()) != null) {
                if (line.equals("--"))  {
                    if (!quote.isEmpty()) {
                        allQuotes.add(quote);
                    }
                    quote = new ArrayList<>();
                } else {
                    quote.add(line);
                }
            }
            if (!quote.isEmpty()) {
                allQuotes.add(quote);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (bufferedReader != null) {
                try {
                    bufferedReader.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return allQuotes;
    }

结果是List<List<String>>：一首诗列表，每首诗都在自己的List<String>中。