public Link(String name, Property from, Property to, boolean isCollection, boolean isNullable) {
public Link(String name, Role from, Role to, boolean isCollection, boolean isNullable) {
    public Link(String name, Property from, Property to,		boolean isCollection, boolean isNullable) {        super(name);        m_from = from;	m_to = to;	m_isCollection = isCollection;	m_isNullable = isNullable;    }