How get object by spring?

How get object by spring?

I have class
public class Skill{
Integer id;
String name;
//set get
}
On page I have form:
<input type="checkbox" id="${skill.id}" name="skills"
value="${skill.name}" checked />
when application start on page this html:
<input type="checkbox" id="2" name="skills" value="php" checked="">
spring correctly read name(==value(=='php')), but id don't read
I read using @ModelAttribute annotation
How to read id value to id?