Add ability to generate named parametrrs in a version independent way

hapi-fhir-base/src/main/java/ca/uhn/fhir/util/ParametersUtil.java

@@ -20,10 +20,7 @@ package ca.uhn.fhir.util;
  * #L%
  */
 
-import ca.uhn.fhir.context.BaseRuntimeChildDefinition;
+import ca.uhn.fhir.context.*;
-import ca.uhn.fhir.context.BaseRuntimeElementCompositeDefinition;
-import ca.uhn.fhir.context.FhirContext;
-import ca.uhn.fhir.context.RuntimeResourceDefinition;
 import ca.uhn.fhir.model.primitive.StringDt;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.lang3.Validate;
@@ -107,6 +104,25 @@ public class ParametersUtil {
 		addClientParameter(theContext, theValue, theParameters, paramChild, paramChildElem, theName);
 	}
 
+	/**
+	 * Add a paratemer value to a Parameters resource
+	 *
+	 * @param theContext    The FhirContext
+	 * @param theParameters The Parameters resource
+	 * @param theName       The parameter name
+	 * @param thePrimitiveDatatype The datatype, e.g. "string", or "uri"
+	 * @param theValue The value
+	 */
+	public static void addParameterToParameters(FhirContext theContext, IBaseParameters theParameters, String theName, String thePrimitiveDatatype, String theValue) {
+		Validate.notBlank(thePrimitiveDatatype, "thePrimitiveDatatype must not be null or empty");
+
+		BaseRuntimeElementDefinition<?> datatypeDef = theContext.getElementDefinition(thePrimitiveDatatype);
+		IPrimitiveType<?> value = (IPrimitiveType<?>) datatypeDef.newInstance();
+		value.setValueAsString(theValue);
+
+		addParameterToParameters(theContext, theParameters, theName, value);
+	}
+
 	private static IBase createParameterRepetition(FhirContext theContext, IBaseResource theTargetResource, BaseRuntimeChildDefinition paramChild, BaseRuntimeElementCompositeDefinition<?> paramChildElem, String theName) {
 		IBase parameter = paramChildElem.newInstance();
 		paramChild.getMutator().addValue(theTargetResource, parameter);

hapi-fhir-structures-r4/src/test/java/ca/uhn/fhir/util/ParametersUtilR4Test.java

@@ -3,14 +3,29 @@ package ca.uhn.fhir.util;
 import ca.uhn.fhir.context.FhirContext;
 import org.hamcrest.MatcherAssert;
 import org.hamcrest.Matchers;
+import org.hl7.fhir.instance.model.api.IBaseParameters;
 import org.hl7.fhir.r4.model.Parameters;
 import org.hl7.fhir.r4.model.StringType;
 import org.junit.Test;
 
 import java.util.List;
 
+import static org.junit.Assert.assertEquals;
+
 public class ParametersUtilR4Test {
 
+	@Test
+	public void testCreateParameters() {
+		FhirContext ctx = FhirContext.forR4();
+
+		IBaseParameters parameters = ParametersUtil.newInstance(ctx);
+		ParametersUtil.addParameterToParameters(ctx, parameters, "someString", "string", "someStringValue");
+		ParametersUtil.addParameterToParameters(ctx, parameters, "someDate", "date", "2019");
+
+		String encoded = ctx.newJsonParser().encodeResourceToString(parameters);
+		assertEquals("{\"resourceType\":\"Parameters\",\"parameter\":[{\"name\":\"someString\",\"valueString\":\"someStringValue\"},{\"name\":\"someDate\",\"valueDate\":\"2019\"}]}", encoded);
+	}
+
 	@Test
 	public void testGetValues(){
 		Parameters p = new Parameters();

src/changes/changes.xml

@@ -43,6 +43,11 @@
 				A Google Analytics script fragment was leftover in the hapi-fhir-jpaserver
 				example and starter projects. Thanks to Patrick Werner for removing these!
 			</action>
+			<action type="add">
+				ParametersUtil now has a utility method that can be used to add parameter values
+				using the string name of the datatype (e.g. "dateTime") in order to help
+				building Parameters resources in a version-independent way.
+			</action>
 		</release>
 		<release version="3.7.0" date="2019-02-06" description="Gale">
 			<action type="add">