Java BufferedOutputStream - BufferedOutputStream In Java

import java.io.*;

class BufferedOutputStreamDemo
{
    public static void main(String arg[])
    {
        File source = new File("E:JavaPrograms\\FolderOne\\fileOne.txt"); 
        // LINE A
        BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(source)); 
        if(source.exists()) 
        {
            System.out.println("File exists.");
        
            
             byte b[] = {'M','E','R','I','T',' ' ,'C','A','M','P','U','S'};
            // Writing into file fileOne
             bos.write(b); // LINE B
             bos.flush(); // LINE C
             bos.close();
        }
        else
            System.out.println("File not found.");
        //bos.close(); 
        
        //Now retrieving data from fileOne
        // LINE D
        BufferedInputStream bis = new BufferedInputStream(new FileInputStream(source)); 
        int c =0;
        while((c = bis.read())!= -1)
            System.out.print((char)c);
        bis.close();
    
    }
}