扫描仪读取大文件 [英] Scanner reading large file

问题描述

我正在玩Scanner类用于学习目的，我用它来读取一个非常大的文件（60.000行aprox）而不使用Reader类，它在大约400行后停止读取。我是否必须在Scanner的构造函数中使用Bufferedreader，否则问题是什么？我想知道为什么会这样。谢谢。
我的代码是输出所有行的常用代码。

I am playing around with the Scanner class for learning purposes and i use it to read a very large file (60.000 lines aprox) without using the Reader class , and it stops reading after approximately 400 lines. Do i have to use a Bufferedreader inside the Scanner's constructor or the problem is something else? I want to know why this is happening. Thanks. My code is the usual code to output all the lines.

File file1 = new File("file1");
Scanner in= new Scanner(file1);
while  (scan.hasNextLine()  ) {
String str = scan.nextLine();
System.out.println(str);
}

推荐答案

这个问题通常比较常见在64位计算机上或使用大小超过1-2 GB的文件，并且与堆空间无关。切换到BufferedReader它应该可以正常工作，

This issue is usually more common on 64 bit machines or with files having size more than 1-2 GB and does not have anything to do with heap space. Switch to BufferedReader it should work fine,

BufferedReader br = new BufferedReader(new FileReader(filepath));
String line = "";
while((line=br.readLine())!=null)
{
    // do something
}

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