io.netty.resolver.dns.AuthoritativeDnsServerCache Maven / Gradle / Ivy
/*
* Copyright 2018 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.resolver.dns;
import io.netty.channel.EventLoop;
import java.net.InetSocketAddress;
/**
* Cache which stores the nameservers that should be used to resolve a specific hostname.
*/
public interface AuthoritativeDnsServerCache {
/**
* Returns the cached nameservers that should be used to resolve the given hostname. The returned
* {@link DnsServerAddressStream} may contain unresolved {@link InetSocketAddress}es that will be resolved
* when needed while resolving other domain names.
*
* @param hostname the hostname
* @return the cached entries or an {@code null} if none.
*/
DnsServerAddressStream get(String hostname);
/**
* Caches a nameserver that should be used to resolve the given hostname.
*
* @param hostname the hostname
* @param address the nameserver address (which may be unresolved).
* @param originalTtl the TTL as returned by the DNS server
* @param loop the {@link EventLoop} used to register the TTL timeout
*/
void cache(String hostname, InetSocketAddress address, long originalTtl, EventLoop loop);
/**
* Clears all cached nameservers.
*
* @see #clear(String)
*/
void clear();
/**
* Clears the cached nameservers for the specified hostname.
*
* @return {@code true} if and only if there was an entry for the specified host name in the cache and
* it has been removed by this method
*/
boolean clear(String hostname);
}