And don't forget that you can also use open to start external programs: 
open($javain, "java ... |") or die "....";
while (<$javain>) {
  #receive the output
}
close($javain);
#
# or
#
open($javaout, "| java ...") or die "....";
foreach (@inputline) {
  print $javaout $_;
  #send some input
}
close($$javaout);

[download]
Key thing is the pipe "|".
$\=~s;s*.*;q^|D9JYJ^^qq^\//\\\///^;ex;print

In reply to Re^2: Testing Java code by Skeeve
in thread Testing Java code by drawde83

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