Freemarker expression is nulled

The following examples refer to freemarker’s official documentation. In Freemarker, the default is an error if the expression is empty. So we need to nullate the expression.

• Attribute is null
  • #{myobj.myProp! }If myProp is empty, no error is reported;
• Return the default value
  • #{myobj.myProp!" The default value "}If myProp is empty, no error is reported and “Default” is returned. This will only work if myProp is empty, but myobj will still work if myProp is empty.
• Objects and properties are nulled
  • #{(myobj.myProp)!" The default value "}If myobj is empty or myProp is empty, no error is reported and “default” is returned.