// implement the C-lang binary 'cp' in Java

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.FileNotFoundException;

import java.io.IOException;

class CopyFile {

public static void main(String[] args) {

// character placeholder

int i;

// check command-line argument number

if (args.length != 2) {

System.out.println("Wrong number of arguments.");

System.out.println("Usage: CopyFile <file_in> <file_out>");

return;

}

// buffer the input file and write to output file

// use the 'try' context manager

try(FileInputStream aFileIn = new FileInputStream(args[0]);

FileOutputStream aFileOut = new FileOutputStream(args[1])) {

do {

// possible to do in a single line without buffering

// but that removes the extra -1 sanity check

i = aFileIn.read();

if (i != -1) aFileOut.write(i);

} while (i != -1);

} catch (IOException aExc) {

System.out.println("I/O Error: " + aExc);

}

}

}