Java tutorial
/* * Copyright 2012 The Netty Project * * The Netty Project licenses this file to you under the Apache License, * version 2.0 (the "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. */ package io.netty.channel; import io.netty.buffer.ByteBufAllocator; import io.netty.util.AbstractConstant; import io.netty.util.ConstantPool; import io.netty.util.internal.ObjectUtil; import java.net.InetAddress; import java.net.NetworkInterface; /** * A {@link ChannelOption}allows to configure a {@link ChannelConfig} in a type-safe * way. Which {@link ChannelOption} is supported depends on the actual implementation * of {@link ChannelConfig} and may depend on the nature of the transport it belongs * to. * * @param <T> the type of the value which is valid for the {@link ChannelOption} */ public class ChannelOption<T> extends AbstractConstant<ChannelOption<T>> { private static final ConstantPool<ChannelOption<Object>> pool = new ConstantPool<ChannelOption<Object>>() { @Override protected ChannelOption<Object> newConstant(int id, String name) { return new ChannelOption<Object>(id, name); } }; /** * Returns the {@link ChannelOption} of the specified name. */ @SuppressWarnings("unchecked") public static <T> ChannelOption<T> valueOf(String name) { return (ChannelOption<T>) pool.valueOf(name); } /** * Shortcut of {@link #valueOf(String) valueOf(firstNameComponent.getName() + "#" + secondNameComponent)}. */ @SuppressWarnings("unchecked") public static <T> ChannelOption<T> valueOf(Class<?> firstNameComponent, String secondNameComponent) { return (ChannelOption<T>) pool.valueOf(firstNameComponent, secondNameComponent); } /** * Returns {@code true} if a {@link ChannelOption} exists for the given {@code name}. */ public static boolean exists(String name) { return pool.exists(name); } /** * Creates a new {@link ChannelOption} for the given {@code name} or fail with an * {@link IllegalArgumentException} if a {@link ChannelOption} for the given {@code name} exists. * * @deprecated use {@link #valueOf(String)}. */ @Deprecated @SuppressWarnings("unchecked") public static <T> ChannelOption<T> newInstance(String name) { return (ChannelOption<T>) pool.newInstance(name); } public static final ChannelOption<ByteBufAllocator> ALLOCATOR = valueOf("ALLOCATOR"); public static final ChannelOption<RecvByteBufAllocator> RCVBUF_ALLOCATOR = valueOf("RCVBUF_ALLOCATOR"); public static final ChannelOption<MessageSizeEstimator> MESSAGE_SIZE_ESTIMATOR = valueOf( "MESSAGE_SIZE_ESTIMATOR"); public static final ChannelOption<Integer> CONNECT_TIMEOUT_MILLIS = valueOf("CONNECT_TIMEOUT_MILLIS"); /** * @deprecated Use {@link MaxMessagesRecvByteBufAllocator} * and {@link MaxMessagesRecvByteBufAllocator#maxMessagesPerRead(int)}. */ @Deprecated public static final ChannelOption<Integer> MAX_MESSAGES_PER_READ = valueOf("MAX_MESSAGES_PER_READ"); public static final ChannelOption<Integer> WRITE_SPIN_COUNT = valueOf("WRITE_SPIN_COUNT"); /** * @deprecated Use {@link #WRITE_BUFFER_WATER_MARK} */ @Deprecated public static final ChannelOption<Integer> WRITE_BUFFER_HIGH_WATER_MARK = valueOf( "WRITE_BUFFER_HIGH_WATER_MARK"); /** * @deprecated Use {@link #WRITE_BUFFER_WATER_MARK} */ @Deprecated public static final ChannelOption<Integer> WRITE_BUFFER_LOW_WATER_MARK = valueOf("WRITE_BUFFER_LOW_WATER_MARK"); public static final ChannelOption<WriteBufferWaterMark> WRITE_BUFFER_WATER_MARK = valueOf( "WRITE_BUFFER_WATER_MARK"); public static final ChannelOption<Boolean> ALLOW_HALF_CLOSURE = valueOf("ALLOW_HALF_CLOSURE"); public static final ChannelOption<Boolean> AUTO_READ = valueOf("AUTO_READ"); /** * If {@code true} then the {@link Channel} is closed automatically and immediately on write failure. * The default value is {@code true}. */ public static final ChannelOption<Boolean> AUTO_CLOSE = valueOf("AUTO_CLOSE"); public static final ChannelOption<Boolean> SO_BROADCAST = valueOf("SO_BROADCAST"); public static final ChannelOption<Boolean> SO_KEEPALIVE = valueOf("SO_KEEPALIVE"); public static final ChannelOption<Integer> SO_SNDBUF = valueOf("SO_SNDBUF"); public static final ChannelOption<Integer> SO_RCVBUF = valueOf("SO_RCVBUF"); public static final ChannelOption<Boolean> SO_REUSEADDR = valueOf("SO_REUSEADDR"); public static final ChannelOption<Integer> SO_LINGER = valueOf("SO_LINGER"); public static final ChannelOption<Integer> SO_BACKLOG = valueOf("SO_BACKLOG"); public static final ChannelOption<Integer> SO_TIMEOUT = valueOf("SO_TIMEOUT"); public static final ChannelOption<Integer> IP_TOS = valueOf("IP_TOS"); public static final ChannelOption<InetAddress> IP_MULTICAST_ADDR = valueOf("IP_MULTICAST_ADDR"); public static final ChannelOption<NetworkInterface> IP_MULTICAST_IF = valueOf("IP_MULTICAST_IF"); public static final ChannelOption<Integer> IP_MULTICAST_TTL = valueOf("IP_MULTICAST_TTL"); public static final ChannelOption<Boolean> IP_MULTICAST_LOOP_DISABLED = valueOf("IP_MULTICAST_LOOP_DISABLED"); public static final ChannelOption<Boolean> TCP_NODELAY = valueOf("TCP_NODELAY"); @Deprecated public static final ChannelOption<Boolean> DATAGRAM_CHANNEL_ACTIVE_ON_REGISTRATION = valueOf( "DATAGRAM_CHANNEL_ACTIVE_ON_REGISTRATION"); public static final ChannelOption<Boolean> SINGLE_EVENTEXECUTOR_PER_GROUP = valueOf( "SINGLE_EVENTEXECUTOR_PER_GROUP"); /** * Creates a new {@link ChannelOption} with the specified unique {@code name}. */ private ChannelOption(int id, String name) { super(id, name); } @Deprecated protected ChannelOption(String name) { this(pool.nextId(), name); } /** * Validate the value which is set for the {@link ChannelOption}. Sub-classes * may override this for special checks. */ public void validate(T value) { ObjectUtil.checkNotNull(value, "value"); } }