Parsing "~" in the File class

On the same (Linux) computer, sometimes,
new java.io.File("~").isDirectory()
returns 'true' and, sometimes, it doesn't. To be clearer, in some programs it returns true and in other programs it doesn't.
This is driving me crazy!
PS. I know I should be using System.getProperty("user.home") but ...

mumbles wrote:
On the same (Linux) computer, sometimes,
new java.io.File("~").isDirectory()
returns 'true' and, sometimes, it doesn't. To be clearer, in some programs it returns true and in other programs it doesn't.If it returns true, then in the current directory (system property "user.dir") there is a directory called "~". When you type something like ls ~, it's the shell (bash, zsh, etc.), not the file system, nor the OS, nor java.io.File, that's expanding the ~ into /home/mydir or whatever.
PS. I know I should be using System.getProperty("user.home") but ...But what? Why not do it the right way?

Similar Messages

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allthow all do exist , when I use the f.exists() it returns false !!!!
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Hi
Found my problem - it wasn't the backslahes (one can use both ways '\\' or'/') it was a realy stupid problem..
thanks any way ,
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The File class ignores the file.separator system property?

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Yeah... I've used that before. Never recalled having problems. I can't, however, recall if there were file paths saved.
Just tested with this:
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import java.util.*;
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}created this:
#Tue Jun 21 10:53:38 EDT 2005
file=C\:\\test\\Props.java

Parsing an xml file using xerces DOM parser

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</Item>
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public void init()
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Check This Sample Code....
public void amethod(){
DocumentBuilderFactory dbf = null;
DocumentBuilder docBuilder = null;
Document doc = null;
try{
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}catch(ParserConfigurationException pce){ pce.printStackTrace();
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}catch(SAXException saxe){ saxe.printStackTrace();
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File class

Hello, I have a curiosity question, why doesn't the File+ class provide a method for retrieving the basename of a file excluding the suffix? For example, for the path
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Thanks.

I see your point and it's vaild; however, in Unix I use the command "basename ext" specifying the suffix. I was thinking that they could have done the same thing, for instance, create the following method;
"*+public String getName( String sSuffix )+*"
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File file = new File ( "c:\some\file\path\filename.ext" );
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System.out.println ( file.getName ( "ext" ) );would print the lines;
filename.extfilename>
Problem solved and it would be a nice convenience method :)
Thanks

UrlLoader - replace with File class to access external assets

Hi.
Just reading up on the File class more than anything because I want to develop on mobile devices. Can I substitute all my urlLoader classes with the File class for my games on the web.
var prefsFile:File = File.applicationDirectory;
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I feel like this may be a stupid question but I have to ask.
Cheers

yes, but you probably don't want to use the applicationDirectory because of security issues.
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Moving the files from one directory to another.

It seems that this would be simple but I am not able to do it easily. I just want to move files from one directory to another directory. I tried the file class renameTo as in the following...
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fTo.delete();
fTo.mkdir();
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kris.

That code you have there tries to rename the directory from C:\uhin\batch\outgoing to C:\uhin\batch\outgoing\back. I'm not sure if you can rename directories in general, but even if you can that particular renaming wouldn't work.
However you didn't want to rename the directory in any case. You need to use a File method called listFiles (if I recall correctly... check the API documentation) which returns an array of File objects, representing all the files in that directory. Then loop through that array, and for each File in it, (1) create a new File object with the new name, and (2) call renameTo() to rename the file.

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I've never tried to do this. The two options you have provided should work. I don't know of any others. The second option could be modified to use a Strategy pattern. Make a Handler that jst defers to your real handler. Once you hit the element tha you need, swap out your handler with one that has an empty implemetation.

Upload all the files in a directory

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I don't believe there's any support in pure html forms to accomplish this.
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RenameTo() method in File.class

I want to know in which platforms the renameTo() method in the File class actually move the file to the detination directory. I have checked with Windows. It does move the file to the targetted directory. What about other platforms??

YoungWinston wrote:
supratim wrote:
My concern is if I am sure that that the renameTo() succeeds in doing its thing[By doing a simple renameTo() on a file and check if it is getting moved],
can it supply me any perfomrmance boost compared to normal stream based copying and then deleting the file.I think you'll have to describe what you're trying to do, and what you think your alternatives are, a bit better.
You never know, somebody may have a '3rd way' which is superior to either.
WinstonMost certainly there may be a lot more ways. All I want to know does the renameTo() method works more faster than the normal stram based copying[which includes creating InputStream and OutputStream] which looks ugly[catching FileNotFoundException,IOException etc]. Well don't take the "ugly" word otherwise, this just waht I think.
I have learned that if FileChannel s are used it, it can boost up the copying speed compared to the stream based copying. But channels are normally used where a bigger size of file needs to be transferred. Should I use channels for faster io.
I am so concerned about the speed because it is preciously what I need to do in my current work. I have to do a lot of io[file moving,copying etc] and my files are also not very big[max 3MB,min 3KB], and I want to know the best way to achieve this in a perfect and of course faster way.

File class question

Hi all,
I've been playing with the File class (as a way of learning about it) and am confused about the behaviour of the following code.
This class is uses recursion as a way of getting a file structure.
import java.io.File;
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The command line I use is java FileTest testdir
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Any ideas? Thanks,
dan

When you instantiate the class java.io.File from a String you should use a pathname or depict the parent directory as well as the abstract file name. Or you could use the method listFiles() of the File class.
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How to know the size of the file

hi all ,
how can I know the file Size (like 23K, 45K, 0K)..
if anyone knows please help me
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Just use the length of the File class...

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URI uri = new URI("http",null,"foo",8080,"/foo/images",null,null);
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Try to use search FTP in se37 or checkout the below FM
CALL FUNCTION 'EPS_FTP_MPUT'
EXPORTING
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*   FILE_MASK                  = ' '
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*   OVERWRITE_MODE             = ' '
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*   RECORDS_PER_TRANSFER       = 10
*   MONITOR_TITLE              =
*   MONITOR_TEXT1              =
*   MONITOR_TEXT2              =
*   PROGRESS_TEXT              =
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*   REMOTE_DIRECTORY           =
*   LOCAL_SYSTEM_INFO          =
*   REMOTE_SYSTEM_INFO         =
* TABLES
*   FILE_LIST                  =
* EXCEPTIONS
*   CONNECTION_FAILED          = 1
*   INVALID_VERSION            = 2
*   INVALID_ARGUMENTS          = 3
*   GET_DIR_LIST_FAILED        = 4
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*   STOPPED_BY_USER            = 6
*   OTHERS                     = 7
IF SY-SUBRC <> 0.
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Hi,
I am not sure about this
Do I need to inherit from JFrame in order to get the File class?
I want to have "File" in a standalone class..
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Thanks
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luckiejacky wrote:
Do I need to inherit from JFrame in order to get the File class?Look at the File API and tutorials to answer this question
http://java.sun.com/javase/6/docs/api/java/io/File.html

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Hallo, i am creating a web Application but i need to know the fullpath of a file. I see that in the web based application i can call that FileReference class but with this class i can only get the name of a file and not the fullname. I can do this with the File Class which is avaible in Air Applications. How can i do it with my FlashPlayer application??....
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You can't get that with FileReference on the web (Security reasons). It was
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C

Parsing "~" in the File class

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