fileSize帮助 [英] fileSize help

问题描述

使用上一个答案中的countChars（）方法，编写一个名为fileSize（）的方法，声明如下：

public int fileSize（String name）{

。 ..

}


它计算文件中的字符数，其名称作为名称提供。参数。此方法应返回文件中的字符数，如果发生IOException，则返回-1。




public int fileSize（String name）抛出IOException

{


try {

InputStreamReader isr = new InputStreamReader（new FileInputStream（" name"）））;

int charLength = 0;


while（isr.read（）！= -1）

charLength ++;


返回charLength;

}


catch（例外e）{

返回-1;

}

}


它总是返回-1

我知道哪里出错了？

解决方案

名为name的文件是否为在您当前的工作目录中存在？您可以从Java找到

当前工作目录，如下所示：

< span class =codeLinkonclick =Blur（this，this.parentNode.parentNode，getChildren（this），true）;>展开 | 选择 | Wrap | 行号

但问题是否未说明该文件被称为名称？我提交作品时是否有文件并不重要。

是否与我放置的地方有关尝试{


谢谢对于帮助

但问题是否未说明该文件被称为名称？我提交作品时是否有文件并不重要。

是否与我放置的地方有关尝试{


谢谢对于帮助

不，你的方法应该采用一个String参数，该参数应该是一个文件的名称。字面意思是文件的名称应该是name，即如果你有一个名为fronobulax.foo的文件，那么

。在你当前的工作目录中传递

字符串到你的方法。


亲切的问候，


Jos

Using the countChars() method from the previous answer, write a method called fileSize() declared as follows:
public int fileSize (String name) {
...
}

which counts the number of characters in the file whose name is supplied as the "name" parameter. This method should return the number of characters in the file, or -1 if an IOException occurs.




public int fileSize(String name) throws IOException
{

try {
InputStreamReader isr = new InputStreamReader(new FileInputStream("name"));
int charLength = 0;

while (isr.read() != -1)

charLength++;

return charLength;
}

catch (Exception e) {
return -1;
}
}

it always returns -1
any know where i am going wrong?

解决方案

Does a file named "name" in your current working directory exists? You can find
your current working directory from Java as follows:

Expand|Select|Wrap|Line Numbers

But does the question not state that the file is called "name"? it would not matter whether i have the file or not when i submit my work.
Is it something to do with where i have placed try {

thanks for the help

But does the question not state that the file is called "name"? it would not matter whether i have the file or not when i submit my work.
Is it something to do with where i have placed try {

thanks for the help

Nope, your method is supposed to take a String argument which is supposed to
be the name of a file. Not literally that the name of the file should be "name", i.e.
if you have a file named "fronobulax.foo" in your current working directory pass
that string to your method.

kind regards,

Jos

这篇关于fileSize帮助的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！