Note that Perl also has closures, which Java doesn't have. In some refactoring cases, you might want to use a closure instead of a method - it gives you some of the benefits private methods give you in Java.
But for me, there's a large difference between storing something in a temporary variable, and using a method. Assuming the temporary variable isn't tied, once you put a value in there, you get back the same value each and every time. With a method, that's less clear, certainly when seen from the caller's perspective. For instance:
my $v1 = $v2 + $v2;
my $v3 = $self->m1 + $self->m1;
The first is equivalent to 2 * $v2
, but it's not clear whether the latter is equivalent to 2 * $self->m1
, until you know what m1
And that's a language agnostic issue.