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In Java, how do I find the proper path to open a txt file that's name is provided as a command line arguement?

I'm working on a program that is supposed to take two files as command line arguments, open the files, and read data from the files to make a data structure.
So far, I have been able to make the structure using File() to open the files and Scanner to read the data. The problem is that I have been providing a specific path to the call for File like this
File f1 = new File("F:/MinSpan/resources/cities.txt");
Scanner sc1 = new Scanner(f1);
I don't think this is going to work for the person who tries to run this program, because I have provided the path for where my specific txt files are located - they're on my flash drive (F) and in some folders. Is there a way I can program this to pass some kind of args[] value in for File() based on the cmd arguement the user has provided?
I have already tried just doing new File(args[2]) , and it can't find the file because there is no path.

The reason for that is because, if you are passing in only two paths, args[2] wont return anything, because args[] starts at 0. So you'd want to use:
new File(args[0]);
new File(args[1]);
Does that make sense?

If you're going for something like java -jar program.jar FILE, then have the program check for the String in args[] at index 0.
Then, construct your file. Check if the file exists (in java.io, it's File.exists()) and return an error message to the user if it's wrong.

Android get file using path (in String format)

My app needs to get an existing file for processing. Now I have the path of the file in String format, how can I get the File with it? Is it correct to do this:
File fileToSave = new File(dirOfTheFile);
Here dirOfTheFile is the path of the file. If I implement it in this way, will I get the existing file or the system will create another file for me?

That's what you want to do. If the file exists you'll get it. Otherwise you'll create it. You can check whether the file exists by calling fileToSave.exists() on it and act appropriately if it does not.
The new keyword is creating a File object in code, not necessarily a new file on the device.
I would caution you to not use hardcoded paths if you are for dirOfFile. For example, if you're accessing external storage, call Environment.getExternalStorageDirectory() instead of hardcoding /sdcard.

The File object is just a reference to a file (a wrapper around the path of the file); creating a new File object does not actually create or read the file; to do that, use FileInputStream to read, FileOutputStream to write, or the various File helper methods (like exists(), createNewFile(), etc.) for example to actually perform operations on the path in question. Note that, as others have pointed out, you should use one of the utilities provided by the system to locate directories on the internal or external storage, depending on where you want your files.

try this..
File fileToSave = new File(dirOfTheFile);
if(fileToSave.exists())
{
// the file exists. use it
} else {
// create file here
}
if parent folder is not there you may have to call fileToSave.getParentFile().mkdirs() to create parent folders

File class cannot access file using absolute path

I am trying to access a file using the file class but it works only with below code
File file = new File("s:\\testing\\selenium\\Version8\\locators\\OR.properties");
however I need to use this approach where I go directly to the server:
"\\GIGABYTE\\s-drive\\Testing\\selenium\\Version8\\locators\OR.properties"in which the above will not find the file - very strange
Any clue as to why this is?

To go directly to the server you will need to have 4 slashes as two are actual slashes and 2 are escape characters:
\\\\GIGABYTE\\s-drive\\Testing\\selenium\\Version8\\locators\OR.properties

You can try the below code:
File file = new File("\\\\GIGABYTE\\s-drive\\Testing\\selenium\\Version8\\locators\\OR.properties");
or this:
File file = new File("//GIGABYTE/s-drive/Testing/selenium/Version8/locators/OR.properties");

How to create a Path and a File that does not Exist in Java

This is the problem I have: If part or all of the path does not already exist, the server should create additional directories as necessary in the hierarchy and then create a new file as above.
Files.createDirectories(path);
That's what I am currently using, but it does not create the end file. For example is the path="/hello/test.html" it will create a directory called "hello" and one called "test.html", I want the test.html to be a file. How can I do that?

This is what I did to solve this "problem" or misuse of the libraries.
Files.createDirectories(path.getParent());
Files.createFile(path);
The first line will get the parent directory, so lets say this is what I want to create "/a/b/c/hello.txt", the parent directory will be "/a/b/c/".
The second like will create the file within that directory.

Have you looked at the javadoc? createDirectories only creates... directories. If you're intent on using Files.createDirectories, parse off the file name, call createDirectories passing only the path portion, then create a new file passing the entire path. Otherwise this is a better approach.
Files.createDirectories(path.substring(0, path.lastIndexOf(File.separator)+1));
File yourFile = new File(path);

you can parse the 'path' variable to isolate the file and the directory using delimiter as '/', and do File file = new File(parsedPath); This would work only when you know that you ALWAYS pass the file name at the end of it.
If you know when you are a) creating a directory b) creating a directory and file, you can pass the boolean variable that would describe if file needs to be created or not.

Using File to create directory which contains periods

File testDir = new File("C:\temp\test");
testDir.createNewFile();
As I understand it, the above will create a directory called test in the directory c:\temp
File testDir = new File("C:\temp\test.dir");
testDir.createNewFile();
As I understand it, the above will create a file called test.dir in the directory c:\temp
What should I be doing to the code above if I wish for test.dir to actually be a directory?

No, the first one will create a regular file - after all, that's what you asked it to do:
Atomically creates a new, empty file named by this abstract pathname if and only if a file with this name does not yet exist. The check for the existence of the file and the creation of the file if it does not exist are a single operation that is atomic with respect to all other filesystem activities that might affect the file.
Nothing there says it will create a directory. You'll want to escape the backslashes though, or it's trying to find C:<tab>emp<tab>est
If you want to create a directory, use File.mkdir or File.mkdirs(). You'll still need to escape the backslashes:
File testDir = new File("C:\\temp\\test.dir");
bool created = testDir.mkdir();
(Use mkdirs to create parent directories as well.) The return value tells you whether or not it actually created a directory.

That's not true.
File.createFile() will create a file.
File.mkdir() creates a directory.
http://download.oracle.com/javase/6/docs/api/java/io/File.html

File testDir = new File("C:\temp\test");
testDir.createNewFile();
As I understand it, the above will
create a directory called test in the
directory c:\temp
Wrong - it will create file called "test". Files do not have to have a "filename extension".
To create a directory:
testDir.mkdir();
BTW, this kind of question is most easily and quickly answered by looking at the API doc. Do yourself a favor and get familiar with it.