PackageDescription: ASN1-Types


ASN 1 - Types

Last published: April 2, 2008 by 'kgreek'

Defines 50 Classes
Extends 53 Classes

This packages gathers the elements used in ASN.1 type definitions. Various kinds of 'types' are represented as instances of Type subclasses. Types are derived from other types often by adding some 'constraint' to the parent type definition. Various kinds of constraints are represented as instances of Asn1Constraint subclasses. Definitions of StructuredTypes are mostly comprised of a list of their 'elements' which are expressed in terms of AbstractElement subclasses.

Types are primarily used to drive the marshaling machinery from ASN1 package, however another important capability of types is the ability to 'validate' objects, i.e. validate if a particular Object is a valid value of a given ASN.1 type. This capability is accessible as Type>>permits: message.

LIMITATIONS:
- no support for ANY DEFINED BY
- no support for ASN.1 values: name Type ::= ...
- no support for parameterization of types: Name { Type param } ::= ...
- no support for information classes and objects: CLASS
- no support for presentation context switching types EXTERNAL, EMBEDDED PDV, CHARACTER STRING