Introduction to HAPI - 1

Explanation for HAPI packages;


ca.uhn.hl7v2.app

This package includes Application stuff.

From an HL7 messaging perspective, an Application is a consumer of a messages. Once a parser parses an incoming message, the message would normally be forwarded to an Application of some sort (e.g. a lab system) which would process the message in some way meaningful for it, and then return a response.

If you are wondering how to integrate HAPI into an existing server application, this is probably the place. Create a class that implements Application, then look at Responder and SimpleServer to see how to get HAPI to listen for messages on a socket and pass them to your Application.

ca.uhn.hl7v2.llp

This package includes stuff for working on a Lower Layer Protocol (LLP). And an implementation of "Minimal Lower Layer Protocol" from the HL7 Implementation Guide, Appendix C

The HL7 protocol will be used primarily in network environments. Most of the details of error detection and correction are handled by the lower levels of any reasonable network protocol and are not appropriate for the HL7 Standard. Many mini and mainframe computer systems, however, operate in communication environments that do not provide sufficient lower layer functionality.

In these cases HL7 offers severalalternate lower layer protocols to suit different environments. It is not a requirement of a vendor to implement any of these protocols to be considered HL7 compliant at the encoding rule level.

( See Health Level Seven Implementation Support Guide for further details on LLP. )


ca.uhn.hl7v2.view

This package includes only one class which is a Swing panel that displays the contents of
a Message object in a JTree. The tree currently only expands to the field level (components shown as one node).


ca.uhn.hl7v2.model

This package ( in the hapi-base-.jar ) includes interfaces, abstract classes and exceptions for HL7 data model.  İmplementation of data model is in the generated source jars.

ca.uhn.hl7v2.parser: This package includes a name which doesn't need an explanation :)

ca.uhn.hl7v2.preparser: This package includes classes extracts specified fields from unparsed messages.

ca.uhn.hl7v2.protocol: This package includes classws for HL7 comminication roles and backends.

ca.uhn.hl7v2.conf: This package includes stuff for parsing and validating conformance profile messages.

ca.uhn.hl7v2.validation: This package includes validation utilities for parsed and encoded messages.

ca.uhn.log: This package enhances logging for HAPI.