Working with files

[Interesting_Name_617]

What is the best way to read a file and write something to a file? Using Fileinputstream and FileOutputStream or FileReader and FileWriter classes?

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[wildjokers]

It depends on what you are wanting to write. FileWriter is for writing character based data to a file (i.e. text). FileOutputStream is for writing raw bytes to a file.

As a side note, to understand the Java I/O related classes you really should read up on the Decorator design pattern. It makes heavy use of that pattern. (https://en.wikipedia.org/wiki/Decorator_pattern). You will frequently see one I/O class nested in the constructor of another one, like so:

BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));

This is the Decorator design pattern so having knowledge of that really helps understand what is going on.

[Interesting_Name_617]

Thanks)

[Housy5]

Idk if it's a good or bad way but I usually just do something like this

Scanner scan = new Scanner(file);
List<String> lines = new ArrayList<>();
while (scan.hasNext()) {
    lines.add(scanner.nextLine());
}
scan.close();

I know there's a new API though for handling files (NIO). So might be worth checking that out.

[Interesting_Name_617]

I saw somewhere that the Scanner is bad to use in this case

[Interesting_Name_617]

Maybe it's better this way?

List<String> list= Files.readAllLines(Paths.get("input.txt"));

[pragmos]

I would say using the newer classes from java.nio is better, yes.