Add test case which illustrates issue with XmlParser being unable t…

…o parse a `Document` that it creates.

hapi-test/src/test/java/ca/uhn/hl7v2/parser/XMLParserTest.java

@@ -20,7 +20,9 @@
 import org.junit.Test;
 import org.w3c.dom.Document;
 
+import ca.uhn.hl7v2.DefaultHapiContext;
 import ca.uhn.hl7v2.HL7Exception;
+import ca.uhn.hl7v2.HapiContext;
 import ca.uhn.hl7v2.model.Message;
 import ca.uhn.hl7v2.model.Segment;
 import ca.uhn.hl7v2.model.Type;
@@ -32,6 +34,7 @@
 import ca.uhn.hl7v2.model.v25.message.ORU_R01;
 import ca.uhn.hl7v2.model.v25.segment.OBX;
 import ca.uhn.hl7v2.model.v251.message.ERP_R09;
+import ca.uhn.hl7v2.util.Hl7InputStreamMessageIterator;
 import ca.uhn.hl7v2.util.Terser;
 
 /**
@@ -431,6 +434,36 @@ public void testMessageParseMethodAndEncodeMethodWithEscapes() throws HL7Excepti
 
 	}
 
+
+    /**
+     * <p>
+     *     Test to ensure that we can parse an XML document that we ourselves have encoded.   Starting with a known Pipe message,
+     *     parse it, encode it to XML, and then attempt to parse that resultant XML back to a {@link Message}.  The expectation is that we
+     *     can parse our own XML.
+     * </p>
+     */
+	@Test
+    public void test_ParseEncodedXml() throws Exception {
+
+        // Create a context
+        HapiContext context = new DefaultHapiContext();
+        context.getParserConfiguration().setValidating(false);
+
+        XMLParser xp = context.getXMLParser();
+
+        InputStream str = getClass().getClassLoader().getResourceAsStream("ca/uhn/hl7v2/parser/adt_a03.txt");
+        Hl7InputStreamMessageIterator iter = new Hl7InputStreamMessageIterator(str, context);
+        while (iter.hasNext()) {
+
+            Message msg = iter.next();
+            Document dom = xp.encodeDocument(msg);
+
+            // We would expect to be able to parse this document back to a Message, as we encoded it.
+            Message outmsg = xp.parseDocument(dom, msg.getVersion());
+            outmsg.printStructure();
+        }
+    }
+
 	private String loadFile(String name) throws IOException {
 		return loadFile(name, '\n');
 	}