Erlang:在同一个模块中定义了多个行为？

-module(my_module).
-behavior(gen_server).
-behavior(supervisor).

-export([start_link/0]).
-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]).
-export([init/1, start_child/1, restart_child/1, delete_child/1, terminate_child/1, which_children/0]).

start_link() ->
    gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).

init([]) ->
    {ok, []}.

handle_call(_Request, _From, State) ->
    {reply, ok, State}.

handle_cast(_Request, State) ->
    {noreply, State}.

handle_info(_Info, State) ->
    {noreply, State}.

terminate(_Reason, _State) ->
    ok.

code_change(_OldVsn, State, _Extra) ->
    {ok, State}.

init([]) ->
    {ok, { {one_for_one, 5, 10}, []} }.

start_child(_) ->
    ok.

restart_child(_) ->
    ok.

delete_child(_) ->
    ok.

terminate_child(_) ->
    ok.

which_children() ->
    [].