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Thread: Reading Big File analysis

  1. #1
    Join Date
    Mar 2011
    Thanked 0 Times in 0 Posts

    Default Reading Big File analysis

    I was searching the prohram to read big file (i.e. size more than 4gb). I got the below program and it reads big files. They say that the program doesn't read the whole file at once. I would like to understand how its achieved in below program
    public class BigFile implements Iterable<String>
    private BufferedReader _reader;

    public BigFile(String filePath) throws Exception
    _reader = new BufferedReader(new FileReader(filePath));

    public void Close()
    catch (Exception ex) {}

    public Iterator<String> iterator()
    return new FileIterator();

    private class FileIterator implements Iterator<String>
    private String _currentLine;

    public boolean hasNext()
    _currentLine = _reader.readLine();
    catch (Exception ex)
    _currentLine = null;

    return _currentLine != null;

    public String next()
    return _currentLine;

    public void remove()

    Here’s how you might use it:
    BigFile file = new BigFile("C:\Temp\BigFile.txt");

    for (String line : file)

  2. #2
    Super Moderator Norm's Avatar
    Join Date
    May 2010
    Eastern Florida
    Thanked 2,274 Times in 2,245 Posts

    Default Re: Reading Big File analysis

    Please Edit your post and wrap your code with[code=java]<YOUR CODE HERE>[/code] to get highlighting
    the program doesn't read the whole file at once
    Unless the file has only one line, then the program reads the file one line at a time using the readLine() method.

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