How to know whether a string path is Web URL or a File based

Question

I have a text field to acquire location information (String type) from User. It could be file directory based (e.g. C:\directory) or Web url (e.g. http://localhost:8008/resouces). The system will read some predetermined metadata file from the location.

Given the input string, how can I detect the nature of the path location whether it is a file based or Web URL effectively.

So far I have tried.

URL url = new URL(location); // will get MalformedURLException if it is a file based.
url.getProtocol().equalsIgnoreCase("http");

File file = new File(location); // will not hit exception if it is a url.
file.exist(); // return false if it is a url.

I am still struggling to find a best way to tackle both scenarios. :-(

Basically I would not prefer to explicitly check the path using the prefix such as http:// or https://

Is there an elegant and proper way of doing this?

Answer 1

If you're open to the use of a try/catch scenario being "elegant", here is a way that is more specific:

try {
    processURL(new URL(location));
}
catch (MalformedURLException ex){
    File file = new File(location);
    if (file.exists()) {
        processFile(file);
    }
    else {
        throw new PersonalException("Can't find the file");
    }
}

This way, you're getting the automatic URL syntax checking and, that failing, the check for file existence.