Re: Easy way to read the contants of a folder/directory and output contents to file?
On 12/12/2011 9:42 AM, Thee Chicago Wolf [MVP] wrote:
Iterating through the array wasn't too hard with listFiles (thanks for
that BTW) but I wound up using the following to accomplish what I
needed to get output to the file to work. It was just a simple matter
of the for loop
FileWriter folderOutput = new FileWriter("filelist.txt");
PrintWriter outFile = new PrintWriter(folderOutput);
for(int i = 0; i< list.length; i++)
{
outFile.write(String.valueOf(list[i]+"\n"));
}
folderOutput.close();
This looks like it might work, but it also might not. I'd
suggest using outFile.close() instead of folderOutput.close() to
avoid the possibility that the PrintWriter might be holding on
to a few characters that have not yet been flushed. It might be
best to get rid of the `folderOutput' name altogether, just to
make this particular mistake harder to make.
There are also a few simplifications available. First, there's
an easier way to iterate through an array (rather oddly named `list').
Second, there's no need to use String.valueOf() on a String argument.
Finally, you could use PrintWriter's own methods to deal with line
termination instead of worrying about it yourself.
Putting it all together yields
PrintWriter outFile = new PrintWriter(
new FileWriter("filelist.txt"));
for (File f : list) {
outFile.println(f);
}
outFile.close();
"Production grade" code would probably use outFile.checkError()
to detect any I/O errors that the PrintWriter may have encountered.
Thanks for tips. I'm still learning Java so super-tweaking the code as
you've shown above is not something I'm adept at doing just yet but in
looking at it, I see how it works and it does make sense. But as I've
asked other, using outFile.println yields me output in my file that
looks like so:
file1.txt
<space>
file2.txt
<space>
file3.txt
<space>
<space>
When I use outFile.write, I get:
file1.txt
file2.txt
file3.txt
<space>
I'm obviously going to stick with the cleaner looking output than the
one with extra spaces in it. But do you know why it's doing the extra
spacing with println? Realistically, it *should* just like the output
for what .write does. Any idea?
- Thee Chicago Wolf [MVP]