my $jira=JIRA::Client->new('http://example.com/jira',$user,$pw);

my %custom_fields = $jira->get_custom_fields();
my @custom_field_names = keys %custom_fields;
# if the above is filled with IDs instead of names, use 'values' instead of 'keys'

while (my $issue = $jira->next_issue()) {

  print 'Priority: ', $issue->getPriority, "\n";
  print 'Status  : ', $issue->getStatus,   "\n";

  my @custom_field_values = $jira->get_issue_custom_field_values($issue, @custom_field_names);

  for (my $i=0; $i < @custom_field_names; $i++) {
    print "Custom Field $custom_field_names[$i] : $custom_field_values[$i];
  }
  print '-'x40,$/;
}