io.netty.handler.address.ResolveAddressHandler Maven / Gradle / Ivy
/*
* Copyright 2020 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.ChannelHandler.Sharable;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelOutboundHandlerAdapter;
import io.netty.channel.ChannelPromise;
import io.netty.resolver.AddressResolver;
import io.netty.resolver.AddressResolverGroup;
import io.netty.util.concurrent.Future;
import io.netty.util.concurrent.FutureListener;
import io.netty.util.internal.ObjectUtil;
import java.net.SocketAddress;
/**
* {@link ChannelOutboundHandlerAdapter} which will resolve the {@link SocketAddress} that is passed to
* {@link #connect(ChannelHandlerContext, SocketAddress, SocketAddress, ChannelPromise)} if it is not already resolved
* and the {@link AddressResolver} supports the type of {@link SocketAddress}.
*/
@Sharable
public class ResolveAddressHandler extends ChannelOutboundHandlerAdapter {
private final AddressResolverGroup resolverGroup;
public ResolveAddressHandler(AddressResolverGroup resolverGroup) {
this.resolverGroup = ObjectUtil.checkNotNull(resolverGroup, "resolverGroup");
}
@Override
public void connect(final ChannelHandlerContext ctx, SocketAddress remoteAddress,
final SocketAddress localAddress, final ChannelPromise promise) {
AddressResolver resolver = resolverGroup.getResolver(ctx.executor());
if (resolver.isSupported(remoteAddress) && !resolver.isResolved(remoteAddress)) {
resolver.resolve(remoteAddress).addListener(new FutureListener() {
@Override
public void operationComplete(Future future) {
Throwable cause = future.cause();
if (cause != null) {
promise.setFailure(cause);
} else {
ctx.connect(future.getNow(), localAddress, promise);
}
ctx.pipeline().remove(ResolveAddressHandler.this);
}
});
} else {
ctx.connect(remoteAddress, localAddress, promise);
ctx.pipeline().remove(this);
}
}
}