Java IO: What's the benefit of using a File-object when reading or writing files?

Question

I've been showed to read file using the following pattern:

File path = new File("src/modul/lorem.txt");
FileReader fr = new FileReader(path);    
// ... BufferedReader br = new BufferedReader(fr); ... and so on ...

As far as I know file is a class which represents more a path to class then an actual file: Java Docs Now, when I tried using just a String instead of the File-object ...

 // ...
 FileReader fr = new FileReader("src/modul/lorem.txt");
 // ...

... it worked fine too.

Therefore my question:

What's the purpose of making and using a File-object?

Is there a real benefit? Or is it just a pattern one has seen somewhere and then copied without asking?

Answer 1

This simply depends on your context/requirements.

Java's File class is nothing but an abstraction. It allows you to treat "some thing" knowing that it represents a file system object. Quoting the javadoc:

An abstract representation of file and directory pathnames.

So, in general: if you only need to pass a file name when opening a reader, then a flat string does fine. But as soon as it might be helpful to do other things with that file, then using the abstraction is the way to go.

In other words: keep in mind that a string is just a sequence of characters. It doesn't bear any meaning beyond that. There is no "meta data" there. But as Java is a strictly typed language, we simply have distinct types for things that "mean more" than just "a sequence of characters".

Example: the file class provides methods to check if the file really exists. When using flat strings, you have to wait for the reader to throw an exception at you.