1 /*
2 * Copyright 2024 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.channel;
17
18 import io.netty.util.concurrent.ThreadAwareExecutor;
19 /**
20 * A handle that can be registered to an {@link IoHandler}.
21 * All methods must be called from the {@link ThreadAwareExecutor} thread (which means
22 * {@link ThreadAwareExecutor#isExecutorThread(Thread)} must return {@code true}).
23 *<p>
24 * All the methods are expected to be called from the {@link IoHandler} on which this {@link IoHandle}
25 * was registered via {@link IoHandler#register(IoHandle)}.
26 */
27 public interface IoHandle extends AutoCloseable {
28
29 /**
30 * Be called once there is something to handle.
31 *
32 * @param registration the {@link IoRegistration} for this {@link IoHandle}.
33 * @param ioEvent the {@link IoEvent} that must be handled. The {@link IoEvent} is only valid
34 * while this method is executed and so must not escape it.
35 */
36 void handle(IoRegistration registration, IoEvent ioEvent);
37
38 /**
39 * Called once this {@link IoHandle} was registered and so will start to receive events
40 * via {@link #handle(IoRegistration, IoEvent)}.
41 */
42 default void registered() {
43 // Noop by default.
44 }
45
46 /**
47 * Called once this {@link IoHandle} was unregistered and so will not receive any more events
48 * via {@link #handle(IoRegistration, IoEvent)}.
49 */
50 default void unregistered() {
51 // Noop by default.
52 }
53
54 /**
55 * Called once the {@link IoHandle} should be closed. Even once this method is called this handle might
56 * still receive events via {@link #handle(IoRegistration, IoEvent)} (if it was previous be registered and so its
57 * {@link #registered()} method was called) until the {@link #unregistered()} method is called.
58 */
59 void close() throws Exception;
60 }