java export system out to string

1// Java program to demonstrate redirection in System.out.println()
2import java.io.*;
3  
4public class SystemFact
5{
6    public static void main(String arr[]) throws FileNotFoundException
7    {
8        // Creating a File object that represents the disk file.
9        PrintStream o = new PrintStream(new File("A.txt"));
10  
11        // Store current System.out before assigning a new value
12        PrintStream console = System.out;
13  
14        // Assign o to output stream
15        System.setOut(o);
16        System.out.println("This will be written to the text file");
17  
18        // Use stored value for output stream
19        System.setOut(console);
20        System.out.println("This will be written on the console!");
21    }
22}