Operations on file: Deleting and get size

Question

Hi,
I'm triying to delete a file. I use the following code:
File found = new File (directoryOutputFileWriter+f);
               boolean deleted = found.delete();But when I execute it the boolean deleted it's always false and the file is not deleted.
Then I try to get the size of another file in this way:
File produced = new File(directoryOutputFileWriter+file[0]);
long size = produced.length();but I receive a null value (the file exists and its dimension is over 0 of course).
Why?
How can I solve?
Thanks, bye bye.

Answer 1

Hello,
in my experience the absolute #1 source of astonishment with file operations is loose manual checking (mistyping or misreading).
I suggest you use those traces:
File found = new File (directoryOutputFileWriter+f);
System.out.println("File path is"+found.getAbsolutePath());
System.out.println("Does this file exists? "+found.exists());
System.out.println("Is this file really a file? "+found.isFile()); // You may not be able to delete a directory on all platforms
System.out.println("Is this file deleted now? "+found.delete());#2 is developers not reading the javadoc (that states that delete may not succeed), but I acknowledge you have read it, as you're investigating why it hasn't, and not complaining that it has.
#3 is people overlooking OS-specific file management. E.g. Unix-Linux-Window file permissions management all may let you read a file but not delete it (with the unices having a richer set of combinations than windows). The rules for directory deletion are different between Unices and Windows. Etc...
Edited by: jduprez on Jul 5, 2010 9:44 AM
@Mel: I sometimes wish I was that much connected to my wife's mind ;o)
@Joachim: nice catch! Loose manual checking indeed (both on my part and on OP's)...