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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  package org.apache.commons.net.whois;
19  
20  import java.io.IOException;
21  import java.io.InputStream;
22  
23  import org.apache.commons.net.finger.FingerClient;
24  
25  /**
26   * The WhoisClient class implements the client side of the Internet Whois Protocol defined in RFC 954. To query a host you create a WhoisClient instance,
27   * connect to the host, query the host, and finally disconnect from the host. If the whois service you want to query is on a non-standard port, connect to the
28   * host at that port. Here's a sample use:
29   *
30   * <pre>
31   * WhoisClient whois;
32   *
33   * whois = new WhoisClient();
34   *
35   * try {
36   *     whois.connect(WhoisClient.DEFAULT_HOST);
37   *     System.out.println(whois.query("foobar"));
38   *     whois.disconnect();
39   * } catch (IOException e) {
40   *     System.err.println("Error I/O exception: " + e.getMessage());
41   *     return;
42   * }
43   * </pre>
44   */
45  
46  public final class WhoisClient extends FingerClient {
47      /**
48       * The default whois host to query. It is set to whois.internic.net.
49       */
50      public static final String DEFAULT_HOST = "whois.internic.net";
51  
52      /**
53       * The default whois port. It is set to 43 according to RFC 954.
54       */
55      public static final int DEFAULT_PORT = 43;
56  
57      /**
58       * The default whois constructor. Initializes the default port to <code> DEFAULT_PORT </code>.
59       */
60      public WhoisClient() {
61          setDefaultPort(DEFAULT_PORT);
62      }
63  
64      /**
65       * Queries the connected whois server for information regarding the given handle and returns the InputStream of the network connection. It is up to the
66       * programmer to be familiar with the handle syntax of the whois server. You must first connect to a finger server before calling this method, and you
67       * should disconnect after finishing reading the stream.
68       *
69       * @param handle The handle to lookup.
70       * @return The InputStream of the network connection of the whois query. Can be read to obtain whois results.
71       * @throws IOException If an I/O error occurs during the operation.
72       */
73      public InputStream getInputStream(final String handle) throws IOException {
74          return getInputStream(false, handle);
75      }
76  
77      /**
78       * Queries the connected whois server for information regarding the given handle. It is up to the programmer to be familiar with the handle syntax of the
79       * whois server. You must first connect to a whois server before calling this method, and you should disconnect afterward.
80       *
81       * @param handle The handle to lookup.
82       * @return The result of the whois query.
83       * @throws IOException If an I/O error occurs during the operation.
84       */
85      public String query(final String handle) throws IOException {
86          return query(false, handle);
87      }
88  
89  }