package org.hl7.fhir.dstu3.model;
import org.hl7.fhir.exceptions.FHIRException;
/**
* in a language with helper classes, this would be a helper class (at least, the base exgtension helpers would be)
* @author Grahame
*
*/
public class ExtensionHelper {
/**
* @param name the identity of the extension of interest
* @return true if the named extension is on this element. Will check modifier extensions too if appropriate
*/
public static boolean hasExtension(Element element, String name) {
if (element != null && element instanceof BackboneElement)
return hasExtension((BackboneElement) element, name);
if (name == null || element == null || !element.hasExtension())
return false;
for (Extension e : element.getExtension()) {
if (name.equals(e.getUrl()))
return true;
}
return false;
}
/**
* @param name the identity of the extension of interest
* @return true if the named extension is on this element. Will check modifier extensions
*/
public static boolean hasExtension(BackboneElement element, String name) {
if (name == null || element == null || !(element.hasExtension() || element.hasModifierExtension()))
return false;
for (Extension e : element.getModifierExtension()) {
if (name.equals(e.getUrl()))
return true;
}
for (Extension e : element.getExtension()) {
if (name.equals(e.getUrl()))
return true;
}
return false;
}
/**
* @param name the identity of the extension of interest
* @return The extension, if on this element, else null. will check modifier extensions too, if appropriate
*/
public static Extension getExtension(Element element, String name) {
if (element != null && element instanceof BackboneElement)
return getExtension((BackboneElement) element, name);
if (name == null || element == null || !element.hasExtension())
return null;
for (Extension e : element.getExtension()) {
if (name.equals(e.getUrl()))
return e;
}
return null;
}
/**
* @param name the identity of the extension of interest
* @return The extension, if on this element, else null. will check modifier extensions too
*/
public static Extension getExtension(BackboneElement element, String name) {
if (name == null || element == null || !element.hasExtension())
return null;
for (Extension e : element.getModifierExtension()) {
if (name.equals(e.getUrl()))
return e;
}
for (Extension e : element.getExtension()) {
if (name.equals(e.getUrl()))
return e;
}
return null;
}
/**
* set the value of an extension on the element. if value == null, make sure it doesn't exist
*
* @param element - the element to act on. Can also be a backbone element
* @param modifier - whether this is a modifier. Note that this is a definitional property of the extension; don't alternate
* @param uri - the identifier for the extension
* @param value - the value of the extension. Delete if this is null
* @throws Exception - if the modifier logic is incorrect
*/
public static void setExtension(Element element, boolean modifier, String uri, Type value) throws FHIRException {
if (value == null) {
// deleting the extension
if (element instanceof BackboneElement)
for (Extension e : ((BackboneElement) element).getModifierExtension()) {
if (uri.equals(e.getUrl()))
((BackboneElement) element).getModifierExtension().remove(e);
}
for (Extension e : element.getExtension()) {
if (uri.equals(e.getUrl()))
element.getExtension().remove(e);
}
} else {
// it would probably be easier to delete and then create, but this would re-order the extensions
// not that order matters, but we'll preserve it anyway
boolean found = false;
if (element instanceof BackboneElement)
for (Extension e : ((BackboneElement) element).getModifierExtension()) {
if (uri.equals(e.getUrl())) {
if (!modifier)
throw new FHIRException("Error adding extension \""+uri+"\": found an existing modifier extension, and the extension is not marked as a modifier");
e.setValue(value);
found = true;
}
}
for (Extension e : element.getExtension()) {
if (uri.equals(e.getUrl())) {
if (modifier)
throw new FHIRException("Error adding extension \""+uri+"\": found an existing extension, and the extension is marked as a modifier");
e.setValue(value);
found = true;
}
}
if (!found) {
Extension ex = new Extension().setUrl(uri).setValue(value);
if (modifier) {
if (!(element instanceof BackboneElement))
throw new FHIRException("Error adding extension \""+uri+"\": extension is marked as a modifier, but element is not a backbone element");
((BackboneElement) element).getModifierExtension().add(ex);
} else {
element.getExtension().add(ex);
}
}
}
}
public static boolean hasExtensions(Element element) {
if (element instanceof BackboneElement)
return element.hasExtension() || ((BackboneElement) element).hasModifierExtension();
else
return element.hasExtension();
}
}