CopyFile2.java

// implement the C-lang binary 'cp' in Java
// (slightly different version, based on the documentation from Oracle)
import java.io.FileInputStream;
import java.io.FileOutputStream;

import java.io.FileNotFoundException;
import java.io.IOException;

class CopyFile2 {
 public static void main(String[] args) {

 if (args.length != 2) {
 System.out.println("Wrong number of arguments.");
 System.out.println("Usage: CopyFile <file_in> <file_out>");
 return;
 }

 // character placeholder
 int c;
 try(FileInputStream aFileIn = new FileInputStream(args[0]);
 FileOutputStream aFileOut = new FileOutputStream(args[1])) {

 // not 'do...while'!
 while ((c = aFileIn.read()) != -1)
 aFileOut.write(c);
 } catch (IOException aExc) {
 System.out.println("I/O Error: " + aExc);
 aExc.printStackTrace();
 }
 }
}