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;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* 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
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