如何使树具有多种类型的节点，并且每个节点在Java中可以具有多个子节点

public class ClientProperty {
    public class Root{}         //NodeType1

    public class Partner{       //NodeType2
        public String partner_id;
        public String partner_name;
        public int partner_node_id;

        public Partner(String partner_id,String partner_name,int partner_node_id){
            this.partner_id = partner_id;
            this.partner_name = partner_name;
            this.partner_node_id = partner_node_id;
        }
    }

    public class Clients{       //NodeType3
        public String client_name;
        public String client_id;
        public int client_node_id;
        public Map<Enum,List<Enum>> clientproperty = new HashMap<Enum,List<Enum>>();

        public Clients(String client_name, String client_id, int client_node_id,Map<Enum,List<Enum>> clientproperty){
            this.client_name = client_name;
            this.client_id = client_id;
            this.client_node_id = client_node_id;
            this.clientproperty = clientproperty;
        }
    }
    public class Users{         //NodeType4
        public String user_name;
        public String user_id;
        public int user_node_id;

        public Users(String user_id,String user_name, int user_node_id){
            this.user_id = user_id;
            this.user_name = user_name;
            this.user_node_id = user_node_id;
        }
    }
    public class Node{
        Node next;
        Object nodes;

        public Node(){
            next = null;
        }

        public Node(Object nodes, Node next){
            this.nodes = nodes;
            this.next = next;
        }
    }
}