MQdb::DBObject.3pm

Langue: en

Version: 2009-06-03 (debian - 07/07/09)

Section: 3 (Bibliothèques de fonctions)

Sommaire

NAME

MQdb::DBObject - DESCRIPTION of Object

SYNOPSIS

Root class for all objects in MappedQuery toolkit

DESCRIPTION

Root object for toolkit and all derived subclasses. All objects in the MappedQuery structure are designed to be persisted in a database. Here database is a more broad term and can be considered any object persistance systems. Currently the toolkit works with SQL based systems but object databases or custom storage engines are possible. Provides base common methods used by all objects.

AUTHOR

Contact Jessica Severin: jessica.severin@gmail.com

LICENSE

  * Software License Agreement (BSD License)
  * MappedQueryDB [MQdb] toolkit
  * copyright (c) 2006-2009 Jessica Severin
  * All rights reserved.
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *     * Redistributions of source code must retain the above copyright
  *       notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above copyright
  *       notice, this list of conditions and the following disclaimer in the
  *       documentation and/or other materials provided with the distribution.
  *     * Neither the name of Jessica Severin nor the
  *       names of its contributors may be used to endorse or promote products
  *       derived from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS BE LIABLE FOR ANY
  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

APPENDIX

The rest of the documentation details each of the object methods. Internal methods are usually preceded with a _

new

   Description: instance creation method
   Returntype : instance of this Class (subclass)
   Exceptions : none

init

   Description: initialization method which subclasses can extend
   Returntype : $self
   Exceptions : subclass dependent

copy

   Description: Shallow copy which copies all base attributes of object 
                to new instance of same class
   Returntype : same as calling instance
   Exceptions : subclass dependent

class

   Description: fixed string symbol for this class. Must be implemented 
                for each subclass and each subclass within toolkit 
                should return a unique name. used by global  methods.
   Returntype : string
   Exceptions : error if subclass does not redefine

database

   Description: the MQdb::Database where this object is permanently persisted to.
                Here database is any object persistance system.
   Returntype : MQdb::Database
   Exceptions : die if invalid setter value type is provided

primary_id

   Description: the unique identifier for this object within database.
   Returntype : scalar or UNDEF
   Exceptions : none

id

   Description: the unique identifier for this object within database.
                Returns empty string if not persisted.
   Returntype : scalar or ''
   Exceptions : none

db_id

   Description: the worldwide unique identifier for this object.
                A URL-like combination of database, class, and id
   Returntype : string or undef if database is not defined
   Exceptions : none

display_desc

   Description: general purpose debugging method that returns a nice
                human readable description of the object instance contents.
                Each subclass should implement and return a nice string.
   Returntype : string scalar 
   Exceptions : none

display_info

   Description: convenience method which prints the display_desc string
                with a carriage return to STDOUT. useful for debugging.
   Returntype : none
   Exceptions : none

xml

   Description: every object in system should be persistable in XML format.
                returns an XML description of the object and all child objects.
                Each subclass must implement and return a proper XML string.
                Best if one implements xml_start() and xml_end() and use here.
   Returntype : string scalar 
   Exceptions : none 
   Default    : default is a simple xml_start + xml_end

xml_start

   Description: every object in system should be persistable in XML format.
                returns an XML description of the object and all child objects.
                Each subclass should OVERRIDE this method and return a proper XML string.
                xml_start is the primary XML start tag
   Example    : return sprintf("<feature id='%d' name='%d' ..... >", $id, $name....);
   Returntype : string scalar 
   Exceptions : none

xml_end

   Description: every object in system should be persistable in XML format.
                returns an XML description of the object and all child objects.
                Each subclass should OVERRIDE this method and return a proper XML string.
                xml_end is the primary XML end tag 
   Example    : return "</feature>";
   Returntype : string scalar 
   Exceptions : none

simple_xml

   Description: short hand for xml_start() . xml_end()
                Can be used when only the primary XML start tag and attributes are needed
                No need to override if xml_start() and xml_end() are implemented
   Returntype : string scalar 
   Exceptions : none