1 /*
2 * Copyright 2019 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * https://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package io.netty.handler.codec.http.websocketx.extensions;
17
18 import io.netty.handler.codec.http.websocketx.WebSocketFrame;
19
20 /**
21 * Filter that is responsible to skip the evaluation of a certain extension
22 * according to standard.
23 */
24 public interface WebSocketExtensionFilter {
25
26 /**
27 * A {@link WebSocketExtensionFilter} that never skip the evaluation of an
28 * any given extensions {@link WebSocketExtension}.
29 */
30 WebSocketExtensionFilter NEVER_SKIP = new WebSocketExtensionFilter() {
31 @Override
32 public boolean mustSkip(WebSocketFrame frame) {
33 return false;
34 }
35 };
36
37 /**
38 * A {@link WebSocketExtensionFilter} that always skip the evaluation of an
39 * any given extensions {@link WebSocketExtension}.
40 */
41 WebSocketExtensionFilter ALWAYS_SKIP = new WebSocketExtensionFilter() {
42 @Override
43 public boolean mustSkip(WebSocketFrame frame) {
44 return true;
45 }
46 };
47
48 /**
49 * Returns {@code true} if the evaluation of the extension must skipped
50 * for the given frame otherwise {@code false}.
51 */
52 boolean mustSkip(WebSocketFrame frame);
53
54 }