Creation of File object on the fly....

[Gurumurthy Ramamurthy]

Hi all,

I have a string using which I need to create a file object and I don't want to store to the hard-disk.

Is there anyway to create File object from reading the contents from buffer.

Say, for example: I have the string:
String s="hello, this is the contents of the file". I need to create the File object for this contents and I don't want to store/retrive to/from hard-disk.

Thanks,
Guru

[pascal betz]

hi

i dont think that there is way to do this since when you read from a File, you do not read via the File object but through a FileInputStream which is constructed with the File or the filepath (the File classs has no read/write methods). So you should work with InputStream which can be either a FileInputStream (from filesystem) or a ByteArrayInputSteam or a XYZInputStream.


cheers

pascal

[Jeroen Wenting]

File is just a handle to a physical file or directory on disk, it's not equipped to handle memory-mapped files.

[Stefan Wagner]

On linux you may have virtual-filesystem support.
And on dos, you could create a ramdisk too in former times - don't know about today.
Of course this would make installation of your program on different machines difficult...

[Stan James]

I liked Pascal's mention of the streams involved. I'm guessing from your requirement for a File object you are calling a method that expects a file:

public void doSomething( File aFile )
{
   open the file
    read lines ...
}

Could you change the method to want an inputstream argument?

public void doSomething( InputStream aStream )
{
   read the stream
}

This kind of thinking comes up all the time in "test first development" where you write JUnit tests before you write the code. It's dead simple for a unit test to create an input stream froma string, just as you wanted to do, but a real hassle to create a disk file, run the test and erase the disk file.