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Regarding the HL7Message class in Jython scripts, and MD Link 4.3.7 and older

In these older versions, a predecessor of this class was used. The updated successor of that class that is documented on this page has new functionality and provides a more consistent interface than the old class. MD Link Jython code written using the old class will continue to work without alteration in MD Link 4.3.8 and above, but it is recommended that you convert your old code to use the new class when convenient. For help with this code conversion, contact MDI Solutions, or follow this guideline of code changes that will be required.

Old-to-new code conversion instructions

You must first make your code point at the new class. To do that, find any place in your code that creates an old HL7Message object. That was done in two lines; one that looks like this:

from com.mdisolutions.mdlink import HL7Message

and one that looks like this:

hl7msg = HL7Message(textvar)

Remove every instance of the first, and change every instance of the second to this:

hl7msg = util.makeHL7Message(textvar)

If your code includes a 1 argument, like this:

hl7msg = HL7Message(textvar,1)

then you can also replace that with hl7msg = util.makeHL7Message(textvar). If your code contains 0 instead of a 1, then contact MDI Solutions.

Then you must update certain method calls which are incompatible between versions. (Be aware that a single line of your Jython code may require several different modifications, due to falling under several different bullet points below.)

• In the old class, field indexes on MSH segments were effectively counted from 0. In the new class, they are counted from 1. So you must add 1 to every field index argument (within an MSH segment) in your code. For example,

  hl7msg.getField('MSH', 10)

  must be changed to hl7msg.getField('MSH', 11)

  Likewise with the field index arguments to all other methods: setField, getComponent, setComponent, getComponentRep, setComponentRep.

  hl7msg.getField('EVN', 1) (for example) should not be changed; only those methods concerning 'MSH' segments.

• The old class counted all segment indexes starting from 0; the new class counts from 1. So 1 must be added to all segment index arguments, for example

  hl7msg.getSegment(3)

  must be changed to

  hl7msg.getSegment(4)

  Likewise with all segment index arguments to addSegment, and removeSegment, and also setField, getField, setComponent, setComponentRep, getComponent, getComponentRep, etc. (if the method call includes a segment repetition index).

• Similarly, in the old class component indexes were counted from 0, but in the new class they are counted from 1. So add 1 to all component indexes arguments in all methods. For example:

  hl7msg.getComponent('PID', 3, 0)

  to

  hl7msg.getComponent('PID', 3, 1)

• In the new class, the versions of methods with segment repetition index arguments have been removed; the new class addresses segment repetitions with a single 2-tuple argument instead. For example, you must change

  hl7msg.getComponent('ZYX', 7, 3, 4)

  to

  hl7msg.getComponent(('ZYX', 8), 3, 4)

  (Note that the segment index has been increased by one also, as per the second point above.) Do this wherever you deal with repeating segments.

• In the new class, the setComponentRep and getComponentRep methods have been removed; the new class addresses field repetitions a single 2-tuple argument instead. For example,

  hl7msg.setComponentRep('Adrian', 'PID', 5, 3, 2)

  must be replaced with

  hl7msg.setComponent('Adrian', 'PID', (5,4), 2)

  (Note that the field repetition index has been increased by one also.) Likewise for all other versions of setComponentRep/ getComponentRep. The important part is to remove the Rep and put brackets around the field and repetition index, and add 1 to the field repetition argument.

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