private void setCorrectAnnotationReference(StructuredFieldValue struct, IdentityHashMap<Annotation, Integer> originalAnnotations, List<Annotation> newAnnotations) {
        for (Field f : struct.getDataType().getFields()) {
            setCorrectAnnotationReference(struct.getFieldValue(f), originalAnnotations, newAnnotations);
        }
    }
Creates a new SpanTree with the given name and an empty SpanList as its root node.

@param name the name of the span tree
document/src/main/java/com/yahoo/document/annotation/SpanTree.java