protected boolean setIfNull; // default to false
protected boolean setIfEmpty; // default to true
public SetOperation(Element element, SimpleMethod simpleMethod) {
super(element, simpleMethod);
this.field = new ContextAccessor(element.getAttribute("field"));
this.fromField = new ContextAccessor(element.getAttribute("from-field"));
this.valueExdr = new FlexibleStringExpander(element.getAttribute("value"));
this.defaultExdr = new FlexibleStringExpander(element.getAttribute("default-value"));
this.type = element.getAttribute("type");
// default to false, anything but true is false
this.setIfNull = "true".equals(element.getAttribute("set-if-null"));