Package

Arthur Foster

Hillman House, 4, Madeira Road,

Parkstone, Poole, Dorset BH14 9ET

Description of GDMO
Package

e-mail:	arthur@arthurfoster.com
tel:	+44 (01202) 469468
fax:	+44 (01202) 469861

Package Example

The PACKAGE template is used to specify the content of a package. Managed object classes are defined as a collection of packages. These packages may be mandatory or conditional when they are used in a managed object class specification.

Packages bring together a group of characteristics that represent a useful and consistent set of specifications. One purpose of the package is to provide a set of re-useable definitions that can be used in several managed object class specifications.

       name   PACKAGE
            BEHAVIOUR behaviour  ... ;
            ATTRIBUTES
                attribute   properties  .... ;
            ATTRIBUTE GROUPS
                attributegroup   attribute .... ;
            ACTIONS
                action  parameter  ... ;
            NOTIFICATION
                notification  parameter  ... ;
        REGISTERED AS  object identifier;

The behaviour identifier in BEHAVIOUR clause identifies a behaviour template that specifies the associated behaviour. The behaviour definition is optional.

The ATTRIBUTES attribute properties references an attribute by the name of that attribute. This clause is optional.

The properties following the attribute reference specify the way in which the attribute will be used when the package is included in a managed object :

	REPLACE-WITH-DEFAULT
	DEFAULT VALUE
	INITIAL VALUE
	PERMITTED VALUES
	REQUIRED VALUES
	GET
	REPLACE
	ADD
	REMOVE
	DERIVATION RULE

The properties following the attribute can also include a parameter that further qualify the use of the attribute in the package. Typically, parameters are used to define specific error responses, etc.

The ATTRIBUTE GROUPS attributegroup attribute references a attribute group by the name of that attribute group. This clause is optional. The attributes in the attribute list following the attribute group name extend the attribute group.

The ACTIONS action parameter references an action definition by the name of that action. This clause is optional. The parameter list following qualifies the action. The parameters are used to extend the syntax of requests or responses and are typically used to provide specific error responses.

The NOTIFICATION notification parameter references a notification definition by the name of that notification. This clause is optional. The parameter list following qualifies the notification. The parameters are typically used to extend the syntax of requests and responses.

The REGISTERED AS object identifier is a unique identity that is used in the protocol to identify this particular package. This clause is optional, but if the package is used in a conditional package clause it must have a registered value.

REPLACE-WITH-DEFAULT

The attribute property REPLACE-WITH-DEFAULT is included if the attribute has a default value that is set by the replace by default operation.

DEFAULT VALUE

The attribute property DEFAULT VALUE indicates that the attribute has a default value that is used in the replace with default or in the instantiation of objects with no initial values. The format of the DEFAULT VALUE specification is -

either
DEFAULT VALUE value reference
or
DEFAULT VALUE DERIVATION RULE behaviour

INITIAL VALUE

The attribute property INITIAL VALUE is included if the attribute has a mandatory initial value used to set the initial value of the attribute at the time of creation. The format of the INITIAL VALUE specification is -

either
INITIAL VALUE value reference
or
INITIAL VALUE DERIVATION RULE behaviour

PERMITTED VALUES

The attribute property PERMITTED VALUES specifies the restrictions on the values the attribute. The format of the PERMITTED VALUES specification is -

PERMITTED VALUES type reference

REQUIRED VALUES

The attribute property REQUIRED VALUES specifies a restriction on the values the attribute take based on a limitation of the semantics (i.e. it is stronger than permitted). The format of the REQUIRED VALUES specification is -

REQUIRED VALUES type reference

GET

The attribute property GET indicates that the attribute can be retrieved by a M-GET operation.

REPLACE

The attribute property REPLACE indicates that the attribute can be changed by the REPLACE operation (a M-SET operation).

ADD

The attribute property ADD indicates that a value may be added to a set valued attribute using the ADD operation (a M-SET operation). It is only valid on set valued attributes.

REMOVE

The attribute property REMOVE indicates that a value may be removed from a set valued attribute using the REMOVE operation (a M-SET operation). It is only valid on set valued attributes.

DERIVATION RULE

The attribute property DERIVATION RULE is used in conjunction with the INITIAL VALUE and the DEFAULT VALUE specifications. It indicates the value is derived from some other attribute by means of application of the rule. The rule is expressed as a behaviour statement.


Author: Arthur Foster 28 May 2002	Arthur Foster is a founder member of
Author: Arthur Foster 28 May 2002		Hosted by