001/* 002 * ==================================================================== 003 * Licensed to the Apache Software Foundation (ASF) under one 004 * or more contributor license agreements. See the NOTICE file 005 * distributed with this work for additional information 006 * regarding copyright ownership. The ASF licenses this file 007 * to you under the Apache License, Version 2.0 (the 008 * "License"); you may not use this file except in compliance 009 * with the License. You may obtain a copy of the License at 010 * 011 * http://www.apache.org/licenses/LICENSE-2.0 012 * 013 * Unless required by applicable law or agreed to in writing, 014 * software distributed under the License is distributed on an 015 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 016 * KIND, either express or implied. See the License for the 017 * specific language governing permissions and limitations 018 * under the License. 019 * ==================================================================== 020 * 021 * This software consists of voluntary contributions made by many 022 * individuals on behalf of the Apache Software Foundation. For more 023 * information on the Apache Software Foundation, please see 024 * <http://www.apache.org/>. 025 * 026 */ 027package org.apache.http.conn; 028 029import java.net.InetAddress; 030import java.net.UnknownHostException; 031 032/** 033 * Users may implement this interface to override the normal DNS lookup offered 034 * by the OS. 035 * 036 * @since 4.2 037 */ 038public interface DnsResolver { 039 040 /** 041 * Returns the IP address for the specified host name, or null if the given 042 * host is not recognized or the associated IP address cannot be used to 043 * build an InetAddress instance. 044 * 045 * @see InetAddress 046 * 047 * @param host 048 * The host name to be resolved by this resolver. 049 * @return The IP address associated to the given host name, or null if the 050 * host name is not known by the implementation class. 051 */ 052 InetAddress[] resolve(String host) throws UnknownHostException; 053 054}