Java的：读从文件整数到一个数组 [英] Java: Reading integers from a file into an array

问题描述

File fil = new File("Tall.txt");
FileReader inputFil = new FileReader(fil);
BufferedReader in = new BufferedReader(inputFil);

int [] tall = new int [100];

String s =in.readLine();

while(s!=null)
{
    int i = 0;
    tall[i] = Integer.parseInt(s); //this is line 19
    System.out.println(tall[i]);
    s = in.readLine();
}

in.close();

我想使用的文件Tall.txt写入其中所含到一个名为高阵列的整数。它这样做在一定程度上，还当我运行它，它会引发以下异常（：

I am trying to use the file "Tall.txt" to write the integers contained in them into the array named "tall". It does this to some extent, but also when I run it, it throws the following exception (:

Exception in thread "main" java.lang.NumberFormatException: For input string: ""
    at java.lang.NumberFormatException.forInputString(Unknown Source)
    at java.lang.Integer.parseInt(Unknown Source)
    at java.lang.Integer.parseInt(Unknown Source)
    at BinarySok.main(BinarySok.java:19)

到底为什么它这样做，我怎么去除呢？在我看来，我读了文件作为字符串，然后将其转换为整数，这是不是非法的。

Why exactly does it do this, and how do I remove it? As I see it, I read the file as strings, and then convert it to ints, which isn't illegal.

推荐答案

您可能想要做这样的事情（如果你在Java 5和以上）

You might want to do something like this (if you're in java 5 & up)

Scanner scanner = new Scanner(new File("tall.txt"));
int [] tall = new int [100];
int i = 0;
while(scanner.hasNextInt()){
   tall[i++] = scanner.nextInt();
}

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