Java tutorial
/* * Copyright 2017 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.resolver.dns; import io.netty.util.internal.UnstableApi; import java.net.InetAddress; /** * Represents the results from a previous DNS query which can be cached. */ @UnstableApi public interface DnsCacheEntry { /** * Get the resolved address. * <p> * This may be null if the resolution failed, and in that case {@link #cause()} will describe the failure. * @return the resolved address. */ InetAddress address(); /** * If the DNS query failed this will provide the rational. * @return the rational for why the DNS query failed, or {@code null} if the query hasn't failed. */ Throwable cause(); }