1 /* 2 * Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 package impl; 25 26 import java.net.InetAddress; 27 import java.net.UnknownHostException; 28 import java.net.spi.InetAddressResolver; 29 import java.net.spi.InetAddressResolverProvider; 30 import java.util.stream.Stream; 31 32 public class WithBootstrapResolverUsageProvider extends InetAddressResolverProvider { 33 34 public static volatile long numberOfGetCalls; 35 36 @Override 37 public InetAddressResolver get(Configuration configuration) { 38 numberOfGetCalls++; 39 System.out.println("The following provider will be used by current test:" + 40 this.getClass().getCanonicalName()); 41 System.out.println("InetAddressResolverProvider::get() called " + numberOfGetCalls + " times"); 42 43 // We use different names to avoid InetAddress-level caching 44 doLookup("foo" + numberOfGetCalls + ".A.org"); 45 46 // We need second call to test how InetAddress internals maintain reference to a bootstrap resolver 47 doLookup("foo" + numberOfGetCalls + ".B.org"); 48 49 return new InetAddressResolver() { 50 @Override 51 public Stream<InetAddress> lookupByName(String host, LookupPolicy lookupPolicy) 52 throws UnknownHostException { 53 return Stream.of(InetAddress.getByAddress(host, new byte[]{127, 0, 2, 1})); 54 } 55 56 @Override 57 public String lookupByAddress(byte[] addr) throws UnknownHostException { 58 return configuration.builtinResolver().lookupByAddress(addr); 59 } 60 }; 61 } 62 63 // Perform an InetAddress resolution lookup operation 64 private static void doLookup(String hostName) { 65 try { 66 InetAddress.getByName(hostName); 67 } catch (UnknownHostException e) { 68 // Ignore UHE since the bootstrap resolver is used here 69 } 70 } 71 72 @Override 73 public String name() { 74 return "WithBootstrapResolverUsageProvider"; 75 } 76 }