#!/usr/bin/perl

$package = shift || "sockets";

for $file (<*.java>) {
  open IN, $file;
  $line1 = <IN>;
  if ($line1 !~ /^package $package;$/) {
    rename $file, "$file~";
    open OUT, ">$file";
    print OUT "package $package;\n\n$line1";
    while (<IN>) { print OUT $_ }
    close OUT;
  }
  close IN;
}