Unit Testing HL7 Messages with Apache Camel

Apache Camel has an HL7 component that it is very useful when we want to route HL7 messages. In this post I will show, step by step, how to send an HL7 String message, convert it to Hapi Message and the process it.

Step 1:

Add to your pom.xml camel-hl7 dependency:

[xml]

org.apache.camel
camel-core
${camel-version}


org.apache.camel
camel-hl7
${camel-version}

[/xml]
Step 2:
Your test class will need to extend CamelTestSupport, in my case, my test is called HL7CamelCodecTest.
[java]
public class HL7CamelCodecTest extends CamelTestSupport {
…
]
[/java]

Step 3:

– Override createRouteBuilder method and add in the route the hl7 codec. The HL7 component supports type Converter from/to Hapi and String which we will be using in this tutorial.
– (optional) Process the Hl7 message. In this example, we will change the Patient surname.

note: that the “hl7codec” it is just a name, the codec will be register in Step 4.

[java]
@Override
protected RouteBuilder createRouteBuilder() throws Exception {
return new RouteBuilder() {

@Override
public void configure() throws Exception {

from(“mina:tcp://localhost:8877?sync=true&codec=#hl7codec”)

.process(new Processor() {
public void process(Exchange exchange) throws Exception {

//The codec has converted the message from string to Hapi Message
Message message = exchange.getIn().getBody(Message.class);

//Now, we can use the terser to make some changes
Terser terser = new Terser(message);

//We will change the Patient Surname from Wood to INTEGRATION_ENGINEER
terser.set(“/PID-5-1”, “INTEGRATION_ENGINEER”);

exchange.getOut().setBody(message);
}
});
}
};
}
[/java]
Step 4:

– Create a JNDI registry, so we can bind the “hl7codec” label to the actual HL7MLLPCodec.

[java]
protected JndiRegistry createRegistry() throws Exception {
JndiRegistry jndi = super.createRegistry();
jndi.bind(“hl7codec”, new HL7MLLPCodec());
return jndi;
}
[/java]

note: In a production environment you could define the HL7 codec in your Spring XML file:

<bean id=”hl7codec”>

<property name=”charset” value=”iso-8859-1″/>

</bean>

Step 5:

– Create a test. In this example, we are just sending an HL7 String Message, using the processor to change the Patient Surname and printing the outbound Message.

[java]
@Test
public void testHl7Codec() throws Exception {

String inMessage = “MSH|^~\\&|hl7Integration|hl7Integration|||||ADT^A01|||2.3|\r” +
“EVN|A01|20130617154644\r” +
“PID|1|465 306 5961||407623|Wood^Patrick^^^MR||19700101|1|||High Street^^Oxford^^Ox1 4DP~George St^^Oxford^^Ox1 5AP|||||||”;

Object outMessage = template.requestBody(“mina:tcp://localhost:8877?sync=true&codec=#hl7codec”, inMessage);

System.out.println(outMessage.toString());

}
[/java]
Now, you can see that the outbound message contains in the PID segment the patient surname equal to INTEGRATION_ENGINEER.

PID|1|465 306 5961||407623|INTEGRATION_ENGINEER^Patrick^^^MR||19700101|1|||High Street^^Oxford^^Ox1 4DP~George St^^Oxford^^Ox1 5AP

You can find the whole project in github.