ca.uhn.hl7v2.validation

Interface Rule

All Superinterfaces:

Serializable

All Known Subinterfaces:

EncodingRule, MessageRule, PrimitiveTypeRule

All Known Implementing Classes:

ConformanceProfileRule, RegexPrimitiveRule, SizeRule, TrimLeadingWhitespace, WithdrawnDatatypeRule, XMLSchemaRule

public interface Rule
extends Serializable

A testable rule to which HL7 messages (at least certain specific message) should conform. This is the central interface of the new HAPI validation model (as of HAPI 0.4). Previously, the only run-time message validation HAPI performs is within the setValue() methods of the Primitive datatype classes. For example when you called setValue() on a DT an exception was thrown if the String arg was not in the correct DT format. This method served well initially but left us with the following limitations:

1. Sometimes validation is inappropriate (e.g. some of the standard rules, like phone number format, don't make sense in some regions).
2. Couldn't add further optional constraints (such as all timestamps must have a time zone).
3. Couldn't turn off validation to improve performance.
4. Other forms of validation (e.g. conformance profiles, standard DTDs) were not covered.

Thus the new validation model is broader in scope, and is based on validation rules implemented as Rule objects, which can be configured to run or not, as needed, depending on run-time configuration.

There are three kinds of rules:

1. PrimitiveTypeRule: Called when the values of simple datatypes are set, like the existing hard-coded datatype validations (e.g. TNFollowsNorthAmericanFormat).
2. MessageRule: Called when complete message content is to be checked on a parsed message (e.g. conformance profile).
3. EncodingRule: Applied to an encoded message (e.g. validation against a 2.xml Schema, a rule that prohibits empty tags, etc.).

Author:

Bryan Tripp

Method Summary

Methods

Modifier and Type	Method and Description
String	getDescription() Returns a text description of the rule.
String	getSectionReference() A string indicating the section of the HL7 standard from which this rule is derived (if applicable).

Method Detail

getDescription

String getDescription()

Returns a text description of the rule. This description may be used as a message in exceptions generated if validation against the rule fails, or in a user interface for rule configuration.

getSectionReference

String getSectionReference()

A string indicating the section of the HL7 standard from which this rule is derived (if applicable). Like the description, this may be used in an exception message or configuration UI.