java copy file from one directory to another efficiently

1
2private static void copyFileUsingStream(File source, File dest) throws IOException {
3    InputStream is = null;
4    OutputStream os = null;
5    try {
6        is = new FileInputStream(source);
7        os = new FileOutputStream(dest);
8        byte[] buffer = new byte[1024];
9        int length;
10        while ((length = is.read(buffer)) > 0) {
11            os.write(buffer, 0, length);
12        }
13    } finally {
14        is.close();
15        os.close();
16    }
17}
18