MQdb::DBObject (3pm)

Root class for all objects in MappedQuery toolkit

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 \s-1SQL\s0 based systems but object databases or custom storage engines are possible. Provides base common methods used by all objects.

Contact Jessica Severin: [email protected]

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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