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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright 2019 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:
 *
 *   https://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.handler.address;

import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelOutboundHandler;
import io.netty.channel.ChannelOutboundHandlerAdapter;
import io.netty.channel.ChannelPromise;

import java.net.NetworkInterface;
import java.net.SocketAddress;

/**
 * {@link ChannelOutboundHandler} implementation which allows to dynamically replace the used
 * {@code remoteAddress} and / or {@code localAddress} when making a connection attempt.
 * 
 * This can be useful to for example bind to a specific {@link NetworkInterface} based on
 * the {@code remoteAddress}.
 */
public abstract class DynamicAddressConnectHandler extends ChannelOutboundHandlerAdapter {

    @Override
    public final void connect(ChannelHandlerContext ctx, SocketAddress remoteAddress,
                              SocketAddress localAddress, ChannelPromise promise) {
        final SocketAddress remote;
        final SocketAddress local;
        try {
            remote = remoteAddress(remoteAddress, localAddress);
            local = localAddress(remoteAddress, localAddress);
        } catch (Exception e) {
            promise.setFailure(e);
            return;
        }
        ctx.connect(remote, local, promise).addListener(new ChannelFutureListener() {
            @Override
            public void operationComplete(ChannelFuture future) {
                if (future.isSuccess()) {
                    // We only remove this handler from the pipeline once the connect was successful as otherwise
                    // the user may try to connect again.
                    future.channel().pipeline().remove(DynamicAddressConnectHandler.this);
                }
            }
        });
    }

    /**
     * Returns the local {@link SocketAddress} to use for
     * {@link ChannelHandlerContext#connect(SocketAddress, SocketAddress)} based on the original {@code remoteAddress}
     * and {@code localAddress}.
     * By default, this method returns the given {@code localAddress}.
     */
    protected SocketAddress localAddress(
            @SuppressWarnings("unused") SocketAddress remoteAddress, SocketAddress localAddress) throws Exception {
        return localAddress;
    }

    /**
     * Returns the remote {@link SocketAddress} to use for
     * {@link ChannelHandlerContext#connect(SocketAddress, SocketAddress)} based on the original {@code remoteAddress}
     * and {@code localAddress}.
     * By default, this method returns the given {@code remoteAddress}.
     */
    protected SocketAddress remoteAddress(
            SocketAddress remoteAddress, @SuppressWarnings("unused") SocketAddress localAddress) throws Exception {
        return remoteAddress;
    }
}