Trying to get args[] to behave themselves!

Question

Hi Everyone,
I am having some fun trying to make my program totally portable. I am working with File objects and they are not behaving exactly the way I would like.
My program takes a source directory, which is packed full of pictures, and then uses each of these pictures in an automated manner which results in an html page being produced for each picture.
I am trying to allow the program to run totally from the command line with two arguments, one the source directory and one the destination directory.
So when running my program, you would do something like this:
C:\MyJava>java -cp . auto.Initialize_Program C:\Pictures C:\HTML
I use the (String[] args) array to import the two parameters into my program.
It is past this point that the fun starts, when creating a File object in my IDE I used the following code, which is totally functional:
File textFile = new File("C:\\Pictures\\"+final_file_name+".htm");In the above code snippet the "C:\\Pictures\\" section of code points to my destination directory and the final_file_name variable names each file in the destination (of course with a ".htm" extension).
When I try to use the command line arguments, e.g.:
File textFile = new File(args[0] + final_file_name + ".htm");I end up with a whole bunch of html files called PicturesXYZ.htm (where XYZ is the various file names) in the root directory.
Basically the section that used to point to the destination directory is now becoming part of the file name. I have experimented with the pathSeperator() method of class File to no avail.
I need to find some way of telling the program that the args[0] part is in fact a destination directory and not part of the file name. Does anybody have any suggestions as to how I could go about doing this?
Any help would be super.
Regards
Davo

Answer 1

C:\MyJava>java -cp . auto.Initialize_Program C:\Pictures C:\HTML
File textFile = new File(args[0] + final_file_name + ".htm");args[0] doesn't end in a backslash, and final_file_name doesn't begin with a filename. So obviously, you end up with filenames like "C:\PicturesXYZ.htm". To avoid this, you can either add a backslash in the concatenation (or use File.pathSeparator, to be more platform independent:)
File textFile = new File(args[0] + File.pathSeparator + final_file_name + ".htm");Or, you can make a File object representing the directory, and use that as input to the File constructor when makeing the textFile object:
File dir = new File(args[0]);
File textFile = new File(dir, final_file_name + ".htm");