/src/lib/design_patterns/chain_handler.e

 1-- This file is part of a Liberty Eiffel library.
 2-- See the full copyright at the end.
 3--
 4deferred class CHAIN_HANDLER[C_ -> CHAIN_OF_RESPONSIBILITY]
 5   --
 6   -- Part of a chain of responsibility. It must tell if it is able to handle a request, and then handle it.
 7   --
 8
 9feature {CHAIN_OF_RESPONSIBILITY}
10   can_handle (chain: C_): BOOLEAN
11         -- True if the handler can indeed handle a request from the given chain of responsibility.
12      require
13         chain /= Void
14      deferred
15      end
16
17   handle (chain: C_)
18         -- Handle a request from the given chain of responsibility.
19      require
20         chain /= Void
21         can_handle(chain)
22      deferred
23      end
24
25end -- class CHAIN_HANDLER
26--
27-- Copyright (C) 2009-2017: by all the people cited in the AUTHORS file.
28--
29-- Permission is hereby granted, free of charge, to any person obtaining a copy
30-- of this software and associated documentation files (the "Software"), to deal
31-- in the Software without restriction, including without limitation the rights
32-- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
33-- copies of the Software, and to permit persons to whom the Software is
34-- furnished to do so, subject to the following conditions:
35--
36-- The above copyright notice and this permission notice shall be included in
37-- all copies or substantial portions of the Software.
38--
39-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
40-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
41-- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
42-- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
43-- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
44-- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
45-- THE SOFTWARE.