What is the difference between ObjectInputStreamReader and InputStreamReader?

Question

My teacher said that in file server program ObjectInputStreamReader is compulsory to write. When I asked the reason then he said me it is comfortable for file server program. I am thinking that it is not necessary reason. Why InputStreamReader or other alternatives can not be used? what is the advantage of ObjectInputStreamReader over InputStreamReader.

Here code for client/server:

public class Client {
    public static void main(String[] args) {
        Socket s = null;
        ObjectInputStream ois = null;
        ObjectOutputStream oos = null;
        Scanner sc = new Scanner(System.in);

        String data = "";
        try {
            s = new Socket("localhost", 1234);
            System.out.println("client is connectd");

            ois = new ObjectInputStream(s.getInputStream());
            String jai = (String) ois.readObject();
            System.out.println("DATA from SERVER:" + jai);
            oos = new ObjectOutputStream(s.getOutputStream());
        } catch (Exception e) {
            e.printStackTrace();
        }

        System.out.println("Enter file name:");
        try {
            String fil = (String) sc.next();
            OutputStream pw = new FileOutputStream(fil + ".new");
            oos.writeObject(fil);
            data = (String) ois.readObject();
            pw.write(data.getBytes());
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
        System.out.println("Content of file:" + data);
    }
}

Can any one say what is actual reason ?

Answer 1

I think you mean ObjectInputStream and BufferedInputStream (not readers).

ObjectInputStream wraps input stream and provides typed methods that allow reading data of certain type from the stream. For example readDouble(), readObject() etc.

BufferedInputStream does not provide additional API (comparing to regular InputStream). The only thing it does is buffering of data, i.e. it reads data chunk-by-chunk that is much more efficient way than reading byte-by-byte.