Java tutorial
/* * Copyright 2013 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.util.ReferenceCountUtil; import io.netty.util.ReferenceCounted; import io.netty.util.internal.ObjectUtil; import io.netty.util.internal.StringUtil; import java.net.SocketAddress; /** * The default {@link AddressedEnvelope} implementation. * * @param <M> the type of the wrapped message * @param <A> the type of the recipient address */ public class DefaultAddressedEnvelope<M, A extends SocketAddress> implements AddressedEnvelope<M, A> { private final M message; private final A sender; private final A recipient; /** * Creates a new instance with the specified {@code message}, {@code recipient} address, and * {@code sender} address. */ public DefaultAddressedEnvelope(M message, A recipient, A sender) { ObjectUtil.checkNotNull(message, "message"); if (recipient == null && sender == null) { throw new NullPointerException("recipient and sender"); } this.message = message; this.sender = sender; this.recipient = recipient; } /** * Creates a new instance with the specified {@code message} and {@code recipient} address. * The sender address becomes {@code null}. */ public DefaultAddressedEnvelope(M message, A recipient) { this(message, recipient, null); } @Override public M content() { return message; } @Override public A sender() { return sender; } @Override public A recipient() { return recipient; } @Override public int refCnt() { if (message instanceof ReferenceCounted) { return ((ReferenceCounted) message).refCnt(); } else { return 1; } } @Override public AddressedEnvelope<M, A> retain() { ReferenceCountUtil.retain(message); return this; } @Override public AddressedEnvelope<M, A> retain(int increment) { ReferenceCountUtil.retain(message, increment); return this; } @Override public boolean release() { return ReferenceCountUtil.release(message); } @Override public boolean release(int decrement) { return ReferenceCountUtil.release(message, decrement); } @Override public AddressedEnvelope<M, A> touch() { ReferenceCountUtil.touch(message); return this; } @Override public AddressedEnvelope<M, A> touch(Object hint) { ReferenceCountUtil.touch(message, hint); return this; } @Override public String toString() { if (sender != null) { return StringUtil.simpleClassName(this) + '(' + sender + " => " + recipient + ", " + message + ')'; } else { return StringUtil.simpleClassName(this) + "(=> " + recipient + ", " + message + ')'; } } }