You can use File::Find to locate files whose filename indicate that they are of the type you want, then use Archive::Zip to inspect those files:

use strict;
use warnings;

use Data::Dumper;
use File::Find;
use Archive::Zip qw( :ERROR_CODES :CONSTANTS );

my $dir = q{/opt/ibm/db2/V9.5/samples/};

my @files = ();

find(
  sub {
    return unless -f;    # skip non-files
    push @files, $File::Find::name if m/.*(war|ear)$/i;
  },
  $dir
);

foreach my $file (@files) {
  my $zip = Archive::Zip->new();
  if ($zip->read($file) == AZ_OK) {
    my @members = $zip->memberNames();
    print qq{$file has } . scalar(@members) . q{ member(s)};
  }
  else {
    die "failed to open $file";
  }
}
__END__
[download]

$ perl -l 653779.pl
/opt/ibm/db2/V9.5/samples/java/Websphere/OptimisticLocking.war has 76 
+member(s)
/opt/ibm/db2/V9.5/samples/java/Websphere/AccessEmployee.ear has 10 mem
+ber(s)
/opt/ibm/db2/V9.5/samples/repl/asnqwxml/stockticker/dist/stockticker.w
+ar has 15 member(s)
[download]