Java – spring Roo, field enumeration

I'm new to spring MVC and spring roo

What is field enumeration?

How do I enumerate all allowed values?

Is it implemented using lookup tables or check constraints?

Solution

Roo's field enumeration – fieldname – type command adds a private field of the specified enumeration type

You can create enumeration types manually or use the roo command:

roo> enum type --class ~.domain.Colors
roo> enum constant --name BLAU
roo> enum constant --name VERMELL

This creates a color enumeration:

public Enum Colors {
  BLAU,VERMELL
}

You can then define entity fields using enumeration types:

roo> entity --class ~.domain.Foo
roo> field enum --fieldName color --type ~.domain.Colors

This defines the foo entity:

//Annotations and imports ommited for brevity
public class Foo{
     private Colors color;
}

For a complete reference to the roo command, see http://static.springsource.org/spring-roo/reference/html/command-index.html.