(Quick Reference)
nullable
Purpose
Allows a property to be set to
null. By default Grails does not allow
null values for properties.
Examples
Description
Set to
true if the property allows
null values.
This constraint influences
schema generation.
Error Code:
className.propertyName.nullable
Web requests resulting from form submissions will have blank strings, not null, for input fields that have no value. Keep this in mind when doing mass property binding to properties that are not nullable. The default behavior is such that a blank string will not validate for nullable: false since the data binder will convert blank strings to null. This includes empty strings and blank strings. A blank string is any string such that the trim() method returns an empty string. To turn off the conversion of empty strings to null set the grails.databinding.convertEmptyStringsToNull property to false in Config.groovy. See the data binding section for more details on data binding.
// grails-app/conf/Config.groovy// the default value for this property is true
grails.databinding.convertEmptyStringsToNull = false// ...
