标签: bufferedreader

我试图从txt文件(书)中读取,然后将其每一行添加到链表.但是,当我运行代码时,我得到了一个outofmemory错误l.add(line);.你能告诉我这段代码我做错了什么吗？或者,有没有更好的方法来存储String值而不是LinkedList？

非常感谢!

public Book (String bookname) throws java.io.IOException{
    f = new FileReader(bookname);
    b = new BufferedReader(f);
    l = new LinkedList<String>();
    String line = b.readLine();
    while (line != null) {
        l.add(line);
    }
    b.close();
}

我只是想用Java执行一个进程,所以

Runtime runtime = Runtime.getRuntime();
this.process = null;

try {
    this.process = runtime.exec(new String[] {
        properties.getPropertyStr("ffmpegExecutable", "/usr/bin/ffmpeg"),
        "-i", this.streamEntry.getSource(),
        "-vcodec", "copy",
        "-acodec", "copy",
        this.streamEntry.getDestination()
    });
} catch (IOException e) {
    e.printStackTrace();
    return;
}

BufferedReader stdout = new BufferedReader(???process.getOutputStream());

我只是希望能够逐行读取过程的输出.我该怎么做呢？

我有这样的代码:

BufferedReader in = new BufferedReader(new FileReader("C:\file.txt"));
String text = in.readLine();//lets say text is now "asd"

之后我有了一个方法:

private static void doSomething(Enum word){
    ...
}

是否有可能以某种方式将此文本转换为枚举？

我正在尝试阅读URL的内容.BufferedReader的初始化会导致崩溃.

我试过查找人们的解决方案,但无论我做什么,我都会遇到这个错误.

这是我的代码:

 try {
        String sUrl = "http://www.google.com";
        System.out.println("About to create URL.");
        URL url = new URL(sUrl);
        System.out.println("Created URL");

        System.out.println("About to create URLConnection");
        URLConnection urlc = url.openConnection();
        System.out.println("Created URLConnection");

        System.out.println("About to create the BufferedReader");
        BufferedReader bR = new BufferedReader(new 
            InputStreamReader(urlc.getInputStream()));
        System.out.println("Created the BufferedReader");

        System.out.println("About to create a StringBuilder");
        StringBuilder sBuilder = new StringBuilder();
        System.out.println("Created StringBuilder");

        int byteRead;
        System.out.println("About to enter while loop and build string");
        while ((byteRead = bR.read()) != -1)
        {
            sBuilder.append((char) byteRead);
        }
        System.out.println("Built string");

        bR.close();
        System.out.println("Buffered …

我试图从格式如下的文件中提取信息:

1
test@mail.ca|password|false

但是,我似乎ArrayIndexOutOfBounds在运行以下代码时遇到错误,我无法确定原因,因为我认为我的分裂应该正常运行.在以"users"开头的行上获得错误.

        sc = new Scanner (System.in);
        BufferedReader in = new BufferedReader (new FileReader (USAVE));
        int repeats = Integer.parseInt(in.readLine());
        for (int c = 0; c < repeats; c++){
            String info = in.readLine();
            System.out.println (info);
            String[] extracted = info.split("\\|");
            users.addUser(extracted[0], decryptPassword(extracted[1]));
        }
        in.close();

可能是什么问题呢？

编辑:我改变了"|" 到"\ |" 但问题仍然存在.

EDIT2:StackTrace

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 1
at OnlineCommunications.userFromFile(OnlineCommunications.java:165)
at OnlineCommunications.logIn(OnlineCommunications.java:36)
at OnlineCommunications.emailOption(OnlineCommunications.java:593)
at OnlineCommunications.main(OnlineCommunications.java:683)

我上面发布的方法是名为userFromFile.

我试图使用BufferedReader从输入中读取a.它第一次工作,但第二次运行我得到一个例外.

john@fekete:~/devel/java/pricecalc$ java frontend.CUI 
> gsdfgd
Invalid command!
> I/O Error getting string:  java.io.IOException: Stream closed
I/O Error: java.io.IOException: java.io.IOException: Stream closed
> I/O Error getting string:  java.io.IOException: Stream closed
I/O Error: java.io.IOException: java.io.IOException: Stream closed
> I/O Error getting string:  java.io.IOException: Stream closed

它只是在循环中继续运行.我一定错过了什么.

public static void main(String args[]) {
            if (args.length == 0) {
                    while (!exit) {
                            try {
                                    exit = processLine(commandLine());
                            } catch (IOException e) {
                                    System.out.println("I/O Error: " + e);
                            }
                    }
                    System.out.println("Bye!");
            } else if …

我想阅读.txt行以完成任务，然后移至下一行。

为了使程序更快，我想使用多线程，因此每个线程都尝试一行。

问题是，我不希望线程1与线程2尝试同一行。

有任何想法吗？

我正在尝试学习如何使用文本文件中的逐行读取.即使我将txt文件放在同一个src中,控制台也始终将错误显示为 - No such file or directory.

public class ddd {

public static void main(String[] args) {
    FileInputStream fis = null;
    BufferedReader reader = null;
    try {
        fis = new FileInputStream("/dd/src/com/dd/input.txt");
        reader = new BufferedReader(new InputStreamReader(fis));
        System.out
                .println("Reading File line by line using BufferedReader");
        String line = reader.readLine();
        while (line != null) {
            System.out.println(line);
            line = reader.readLine();
        }
    } catch (Exception e) {
        System.out.println(e.getMessage());
    } finally {
        try {
            reader.close();
            fis.close();
        } catch (IOException e) {
            System.out.println(e.getMessage());
        }

    } …

一直在寻找解决此问题的方法。阅读所有先前的答案，但没有一个帮助我。SonarQube可能有任何错误吗？

public class Br {

    public String loader(String FilePath){

        BufferedReader br;
        String str = null;
        StringBuilder strb = new StringBuilder();
        try {
            br = new BufferedReader(new FileReader(FilePath));
            while ((str = br.readLine()) != null) {
                strb.append(str).append("\n");
            }
        } catch (FileNotFoundException f){
            System.out.println(FilePath+" does not exist");
            return null;
        } catch (IOException e) {
            e.printStackTrace();
        }
        return strb.toString();
    }
}

我正在尝试平均一个包含1000万个数字的文件，每行只有一个数字。我创建了一个名为getAverage（）的方法，该方法返回一个double。这是代码：

public double promedioDouble() throws IOException
    {
        double adder = 0;
        int counter = 0;
        try{
                file = new FileReader(filePath);
                reader = new BufferedReader(file);
                while(reader.readLine()!=null)
                {
                    adder+=Double.parseDouble(reader.readLine());
                    counter++;
                }

            }
        catch (IOException e) 
        {
              System.out.println("cant read");
        }
        finally {
            if (file != null) file.close();
        }             
        return adder/counter;
    }

我打印了计数器，结果显示为5.000.000，我不知道为什么读者无法读取文件中包含的1000万个数字，而它只能读取一半。我需要帮助。