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 ThrowingLookupsProviderImpl extends InetAddressResolverProvider {
33     @Override
34     public InetAddressResolver get(Configuration configuration) {
35         System.out.println("The following provider will be used by current test:" +
36                 this.getClass().getCanonicalName());
37 
38         return new InetAddressResolver() {
39             @Override
40             public Stream<InetAddress> lookupAddresses(String host, LookupPolicy lookupPolicy)
41                     throws UnknownHostException {
42                 if (throwRuntimeException) {
43                     System.err.println(name()+" forward lookup: throwing RuntimeException");
44                     throw new RuntimeException(RUNTIME_EXCEPTION_MESSAGE);
45                 } else {
46                     System.err.println(name()+" forward lookup: throwing UnknownHostException");
47                     throw new UnknownHostException();
48                 }
49             }
50 
51             @Override
52             public String lookupHostName(byte[] addr) throws UnknownHostException {
53                 if (throwRuntimeException) {
54                     System.err.println(name()+" reverse lookup: throwing RuntimeException");
55                     throw new RuntimeException(RUNTIME_EXCEPTION_MESSAGE);
56                 } else {
57                     System.err.println(name()+" reverse lookup: throwing UnknownHostException");
58                     throw new UnknownHostException();
59                 }
60             }
61         };
62     }
63 
64     @Override
65     public String name() {
66         return "ThrowingLookupsProvider";
67     }
68 
69     // Indicates if provider need to throw RuntimeException for forward and reverse lookup operations.
70     // If it is set to 'false' then UnknownHostException will thrown for each operation.
71     public static volatile boolean throwRuntimeException;
72     public static final String RUNTIME_EXCEPTION_MESSAGE = "This provider only throws exceptions";
73 }