use strict;
use warnings;

my %dispatch =
    (
        Job => \&job,
        File => \&file,
        Image => \&image,
        # Job => \&add_to_hash, # alternative to job/image subs
    );

my %job_details_info;
my @files;

foreach my $line ( 'Job line', 'File line', 'Image line' )
{
    # use a dispatch table
    if( $line =~ m/(Job|File|Image)/ )
    {
        $dispatch{$1}->($line);
    }

    # group functionality
    if( $line =~ m/(Job|Image)/ )
    {
        $job_details_info{$1} = $line;
    }
    elsif( $line =~ m/File/ )
    {
        push @files, $line;
    }
}

sub job
{
    my ( $line ) = @_;
    $job_details_info{Job} = $line;
}

sub file
{
    my ( $line ) = @_;
    push @files, $line;
}

sub image
{
    my ( $line ) = @_;
    $job_details_info{Image} = $line;
}

# you could combine the job and image subs into something like this
sub add_to_hash
{
    my ( $key, $line ) = @_;
    $job_details_info{$key} = $line;
}