What exactly is System.in?

Question

Hello. I am currently reading a book for Java beginners and I am currently working on a chapter about I/O. This chapter has left me somewhat puzzled, though, because it was explaining that there are 3 predefined streams (in, out, and err) in the System class. Then it said that System.in was an object of the InputStream class. It explained earlier, however, that InputStream was an abstract class and according to the book it is not possible to create objects of abstract classes. So my question would be, how is it possible that System.in is an object of InputStream? If anyone could lend an explanation about this I would be greatly appreciative.

Answer 1

lmao book isnt called Java Gently is it?
try this
import java.io.*;               //Imports libraries for data input
public class IO {
     public static void main (String args[]) throws IOException     {
          String input="";
          BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
          System.out.print("\nENTER YOUR NAME > ");
          input = in.readLine();
          System.out.print("Hello " + name + " !!!");
}