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What is a propertyDescriptor

An object that describes a property of a peanut and supplies default property behavior
A propertyDescriptor defines the name of a property as well as its label. It defines weather the property values can be set: if it is readOnly its values can not be set.

A propertyDescriptor defines constraints for the property: its type,
its minimal and maximal length (of the value as a string),
if applicable its minimal and maximal value,

For field properties of persistent objects it defines weather the properties field value will be stored in the database.

A propertyDescriptor may define the directory of the type. Default is the directory returned by the peanut's getClassDir method.

There are currently three concrete classes of propertyDescriptors: PntFieldPropertyDescriptor for describing fieldProperties, PntDerivedPropertyDescriptor for describing derived properies and PntMultiValuePropertyDescriptor for describing multi value properties. They all reside in the pnt/meta classFolder.