为什么 HAPI 解析器在将 XML 转换为 HL7 时只占用最后一段？

Question

I'm working on HL7 Converter in Java to use with an application I'm developing.

I'm using following HL7 message as a sample input:

MSH|^~\\&|HCEN^^|ASSE^^|INUS^^|SALUD.UY^^|20190307113000^||ADT^A01^ADT_A04|72|P^|2.5|||||||^^^^^
EVN||20190228143000^|^|||^|^^
PID||^^^&&^^&&^^^&^&&|998855^^^ASSE&2.16.858.2.10001442.72768.9&ISO^^&&^^^&&&&&&&&^&&&&&&&&
PV1||U

Following are the two functions I developed:

public static String convertHl7toXml(String hl7MessageString) {
    // instantiate a PipeParser, which handles the "traditional or default encoding"
    PipeParser ourPipeParser = new PipeParser();
    String xmlMessageString = "";

    try {
        // parse the string format message into a Java message object
        Message hl7Message = ourPipeParser.parse(hl7MessageString);

        // instantiate an XML parser
        //HAPI provides 
        XMLParser xmlParser = new DefaultXMLParser();

        xmlMessageString = xmlParser.encode(hl7Message);

    } catch (Exception e) {
        e.printStackTrace();
    }
   return xmlMessageString;
}

public static String convertXmltoHl7(String xmlMessageString) {
    XMLParser xmlParser = new DefaultXMLParser();
    String hl7MessageString = "";

    try {
        Message hl7Message = xmlParser.parse(xmlMessageString);          
        System.out.println(hl7Message.toString());
        HapiContext context = new DefaultHapiContext();
        Parser parser = context.getPipeParser();
        hl7MessageString = parser.encode(hl7Message);            
    } catch (Exception e) {
            e.printStackTrace();
    }   
    return hl7MessageString;
}

I run the conversion from HL7 to XML correctly. This is the resulting output:

<?xml version="1.0" encoding="UTF-8"?>
<ADT_A04 xmlns="urn:hl7-org:v2xml">
    <MSH>
        <MSH.1>|</MSH.1>
        <MSH.2>^~\&amp;</MSH.2>
        <MSH.3>
            <HD.1>HCEN</HD.1>
        </MSH.3>
        <MSH.4>
            <HD.1>ASSE</HD.1>
        </MSH.4>
        <MSH.5>
            <HD.1>INUS</HD.1>
        </MSH.5>
        <MSH.6>
            <HD.1>SALUD.UY</HD.1>
        </MSH.6>
        <MSH.7>
            <TS.1>20190307113000</TS.1>
        </MSH.7>
        <MSH.9>
            <MSG.1>ADT</MSG.1>
            <MSG.2>A01</MSG.2>
            <MSG.3>ADT_A04</MSG.3>
        </MSH.9>
        <MSH.10>72</MSH.10>
        <MSH.11>
            <PT.1>P</PT.1>
        </MSH.11>
        <MSH.12>
            <VID.1>2.3.1</VID.1>
        </MSH.12>
    </MSH>
    <EVN>
        <EVN.2>
            <TS.1>20190228143000</TS.1>
        </EVN.2>
    </EVN>
    <PID>
        <PID.3>
            <CX.1>998855</CX.1>
            <CX.4>
                <HD.1>ASSE</HD.1>
                <HD.2>2.16.858.2.10001442.72768.9</HD.2>
                <HD.3>ISO</HD.3>
            </CX.4>
        </PID.3>
        <PID.3>
            <CX.1>33434343</CX.1>
            <CX.4>
                <HD.1>CI</HD.1>
                <HD.2>2.16.858.2.10000675.68909</HD.2>
                <HD.3>ISO</HD.3>
            </CX.4>
        </PID.3>
        <PID.4>
            <CX.4>
                <HD.3>ISO</HD.3>
            </CX.4>
        </PID.4>
        <PID.5>
            <XPN.1>
                <FN.1>pasdsds</FN.1>
            </XPN.1>
            <XPN.2>juan</XPN.2>
        </PID.5>
        <PID.6>
            <XPN.1>
                <FN.1>dlsdsds</FN.1>
            </XPN.1>
        </PID.6>
        <PID.7>
            <TS.1>19890203</TS.1>
        </PID.7>
        <PID.8>1</PID.8>
        <PID.11>
            <XAD.1>Colonia 1652</XAD.1>
            <XAD.3>MONTEVIDEO</XAD.3>
            <XAD.4>MONTEVIDEO</XAD.4>
            <XAD.6>URUGUAY</XAD.6>
            <XAD.7>H</XAD.7>
        </PID.11>
    </PID>
    <PV1>
        <PV1.2>U</PV1.2>
    </PV1>
</ADT_A04>

After that I try to convert the XML back to HL7 but the result is just:

PV1||U

If I try with just one segment, no matter which one, the result is correct. But when trying with more than one segments, it always returns the last one.

Why HAPI parser is taking only last segment while converting XML to HL7?

Answer 1

I have modified your code to work in C#/.NET Core. And it worked for your XML and other hl7Xml. You can follow this and do the same modification in Java code.

public static String ConvertXmltoHl7(String xmlMessageString)
{
    XMLParser xmlParser = new DefaultXMLParser();
    IMessage hl7Message = xmlParser.Parse(xmlMessageString);
    PipeParser pipeParser = new PipeParser();
    String hl7MessageString = pipeParser.Encode(hl7Message);
    return hl7MessageString;
}

xmlMessageString (Parmeter to ConvertXmltoHl7 method)

<?xml version="1.0" encoding="UTF-8"?>
<ADT_A04 xmlns="urn:hl7-org:v2xml">
    <MSH>
        <MSH.1>|</MSH.1>
        <MSH.2>^~\&amp;</MSH.2>
        <MSH.3>
            <HD.1>HCEN</HD.1>
        </MSH.3>
        <MSH.4>
            <HD.1>ASSE</HD.1>
        </MSH.4>
        <MSH.5>
            <HD.1>INUS</HD.1>
        </MSH.5>
        <MSH.6>
            <HD.1>SALUD.UY</HD.1>
        </MSH.6>
        <MSH.7>
            <TS.1>20190307113000</TS.1>
        </MSH.7>
        <MSH.9>
            <MSG.1>ADT</MSG.1>
            <MSG.2>A01</MSG.2>
            <MSG.3>ADT_A04</MSG.3>
        </MSH.9>
        <MSH.10>72</MSH.10>
        <MSH.11>
            <PT.1>P</PT.1>
        </MSH.11>
        <MSH.12>
            <VID.1>2.3.1</VID.1>
        </MSH.12>
    </MSH>
    <EVN>
        <EVN.2>
            <TS.1>20190228143000</TS.1>
        </EVN.2>
    </EVN>
    <PID>
        <PID.3>
            <CX.1>998855</CX.1>
            <CX.4>
                <HD.1>ASSE</HD.1>
                <HD.2>2.16.858.2.10001442.72768.9</HD.2>
                <HD.3>ISO</HD.3>
            </CX.4>
        </PID.3>
        <PID.3>
            <CX.1>33434343</CX.1>
            <CX.4>
                <HD.1>CI</HD.1>
                <HD.2>2.16.858.2.10000675.68909</HD.2>
                <HD.3>ISO</HD.3>
            </CX.4>
        </PID.3>
        <PID.4>
            <CX.4>
                <HD.3>ISO</HD.3>
            </CX.4>
        </PID.4>
        <PID.5>
            <XPN.1>
                <FN.1>pasdsds</FN.1>
            </XPN.1>
            <XPN.2>juan</XPN.2>
        </PID.5>
        <PID.6>
            <XPN.1>
                <FN.1>dlsdsds</FN.1>
            </XPN.1>
        </PID.6>
        <PID.7>
            <TS.1>19890203</TS.1>
        </PID.7>
        <PID.8>1</PID.8>
        <PID.11>
            <XAD.1>Colonia 1652</XAD.1>
            <XAD.3>MONTEVIDEO</XAD.3>
            <XAD.4>MONTEVIDEO</XAD.4>
            <XAD.6>URUGUAY</XAD.6>
            <XAD.7>H</XAD.7>
        </PID.11>
    </PID>
    <PV1>
        <PV1.2>U</PV1.2>
    </PV1>
</ADT_A04>

hl7MessageString (return value of ConvertXmltoHl7 method)

MSH|^~\&|HCEN|ASSE|INUS|SALUD.UY|20190307113000||ADT^A01^ADT_A04|72|P|2.3.1
EVN||20190228143000
PID|||998855^^^ASSE&2.16.858.2.10001442.72768.9&ISO~33434343^^^CI&2.16.858.2.10000675.68909&ISO|^^^&&ISO|pasdsds^juan|dlsdsds|19890203|1|||Colonia 1652^^MONTEVIDEO^MONTEVIDEO^^URUGUAY^H
PV1||U