import java.io.*;
import java.util.*;

public class CopyBinFile {
  public static void main(String [] args) {
    
    Scanner sc = new Scanner(System.in);
    System.out.print("Enter src filename: ");
    String readFilename = sc.next();
    File readFile = new File(readFilename);
    
    if( !readFile.isFile() ) {
      System.err.println("Input file does not exist or is not a regular file!");
      return;
    }
    if( !readFile.canRead() ) {
      System.err.println("Input file is not readable!");
      return;
    }
    
    System.out.print("Enter dst filename: ");
    String writeFilename = sc.next();
    File writeFile = new File(writeFilename);
    
    if( writeFile.exists() ) {
      System.err.println("Output file exists! Unable to overwrite.");
      return;
    }
    
    try {
      byte []buffer = new byte[2048];
      FileInputStream in = new FileInputStream(readFile);
      FileOutputStream out = new FileOutputStream(writeFile);
      int read_len;
      while( (read_len = in.read(buffer)) != -1 ) {
        out.write(buffer, 0, read_len);
      }
      out.close();
      in.close();
    } catch( IOException ex ) {
      ex.printStackTrace();
    }
  }
}