Solved

PERL 5.8:: Need to have classes and objects

Posted on 2008-10-02
4
195 Views
Last Modified: 2012-05-05
I need a sample for how to create and object of a class in perl. Pass this object to another class

Explanation
====
main code
=======
#!/usr/bin/perl

use utility;
use blobManage;


my $utility = new utility;

# How to pass a reference of utility object to blobManage

my $blMng = new blobManage;



==========================
blobManage.pm
================

package blobManage;

warn "blobManage is successfully loaded!\n";
1;
use utility;
use File::Copy;
# How to declare, set and use the reference of the utility object.
sub new {
       my ($class_name) = @_;

        my ($self) = {};

            #my ref $utility ;
#       warn "We just created our new variable...\n ";

        bless ($self, $class_name);
#        warn "and now it's a $class_name object!\n";

        $self->{'_created'} = 1;
        return $self;
}

0
Comment
Question by:EmadGirgis
  • 2
  • 2
4 Comments
 
LVL 39

Expert Comment

by:Adam314
ID: 22628577

#You can pass the utility when creating the blobManage:
my $blMng = new blobManage($utility);
 
 
 
 
package blobManage;
...
sub new {
    my ($class_name, $util) = @_;
    #now, $util is a reference to the same object as $utility in your main program

Open in new window

0
 

Author Comment

by:EmadGirgis
ID: 22628608
and $util is visible for all functions of the blobManage class

If I have a sub doSomething in blobManage

doSomething{

$util->doSomethingelse();
}
Would that work
0
 

Author Comment

by:EmadGirgis
ID: 22628641
Do I need to bless $utility

What is bless anyway? I
0
 
LVL 39

Accepted Solution

by:
Adam314 earned 500 total points
ID: 22629130
The bless function turns a reference into an object.
http://perldoc.perl.org/functions/bless.html

If you want $utility to be available to the blobManage from the new function, you'll have to save it in the blobManage object.

If you just want one function of the blobManage object to use the utility object, you can pass it to that function.


Here are examples of both

############################## blobManage keeps a reference to the utility object
#create utility object
my $utility = new utility;
...
#You can pass the utility when creating the blobManage:
my $blMng = new blobManage($utility);
$blMng->doSomething(); 
 
 
 
package blobManage;
...
sub new {
    my ($class_name, $util) = @_;
    #now, $util is a reference to the same object as $utility in your main program
    
    my $self = {utility => $util};
    bless $self, $class_name;
    ...
    return $self;
}
 
sub doSomething {
    my $self = shift;
    $self->{utility}->doSomethingElse
}
 
############################## blobManage does not keep a reference to the utility object
############################## it gets the reference only for the functions that need it
 
#create utility object
my $utility = new utility;
...
#You can pass the utility when creating the blobManage:
my $blMng = new blobManage();
$blMng->doSomething($utility); 
 
 
 
 
package blobManage;
...
sub new {
    my ($class_name) = @_;
    #now, $util is a reference to the same object as $utility in your main program
    
    my $self = {};
    bless $self, $class_name;
    ...
    return $self;
}
 
sub doSomething {
    my ($self, $util) = @_;
    #do stuff with $self
    $util->doSomethingElse();
}

Open in new window

0

Featured Post

Free Tool: Site Down Detector

Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Many time we need to work with multiple files all together. If its windows system then we can use some GUI based editor to accomplish our task. But what if you are on putty or have only CLI(Command Line Interface) as an option to  edit your files. I…
In the distant past (last year) I hacked together a little toy that would allow a couple of Manager types to query, preview, and extract data from a number of MongoDB instances, to their tool of choice: Excel (http://dilbert.com/strips/comic/2007-08…
Explain concepts important to validation of email addresses with regular expressions. Applies to most languages/tools that uses regular expressions. Consider email address RFCs: Look at HTML5 form input element (with type=email) regex pattern: T…

789 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question