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 package org.apache.commons.net.finger;
18
19 import java.io.BufferedOutputStream;
20 import java.io.BufferedReader;
21 import java.io.DataOutputStream;
22 import java.io.IOException;
23 import java.io.InputStream;
24 import java.io.InputStreamReader;
25
26 import org.apache.commons.net.SocketClient;
27 import org.apache.commons.net.util.Charsets;
28
29 /**
30 * The FingerClient class implements the client side of the Internet Finger Protocol defined in RFC 1288. To finger a host you create a FingerClient instance,
31 * connect to the host, query the host, and finally disconnect from the host. If the finger service you want to query is on a non-standard port, connect to the
32 * host at that port. Here's a sample use:
33 *
34 * <pre>
35 * FingerClient finger;
36 *
37 * finger = new FingerClient();
38 *
39 * try {
40 * finger.connect("foo.bar.com");
41 * System.out.println(finger.query("foobar", false));
42 * finger.disconnect();
43 * } catch (IOException e) {
44 * System.err.println("Error I/O exception: " + e.getMessage());
45 * return;
46 * }
47 * </pre>
48 */
49
50 public class FingerClient extends SocketClient {
51 /**
52 * The default FINGER port. Set to 79 according to RFC 1288.
53 */
54 public static final int DEFAULT_PORT = 79;
55
56 private static final String LONG_FLAG = "/W ";
57
58 private final transient char[] buffer = new char[1024];
59
60 /**
61 * The default FingerClient constructor. Initializes the default port to <code> DEFAULT_PORT </code>.
62 */
63 public FingerClient() {
64 setDefaultPort(DEFAULT_PORT);
65 }
66
67 /**
68 * Fingers the connected host and returns the input stream from the network connection of the finger query. This is equivalent to calling
69 * getInputStream(longOutput, ""). You must first connect to a finger server before calling this method, and you should disconnect after finishing reading
70 * the stream.
71 *
72 * @param longOutput Set to true if long output is requested, false if not.
73 * @return The InputStream of the network connection of the finger query. Can be read to obtain finger results.
74 * @throws IOException If an I/O error during the operation.
75 */
76 public InputStream getInputStream(final boolean longOutput) throws IOException {
77 return getInputStream(longOutput, "");
78 }
79
80 /**
81 * Fingers a user and returns the input stream from the network connection of the finger query. You must first connect to a finger server before calling
82 * this method, and you should disconnect after finishing reading the stream.
83 *
84 * @param longOutput Set to true if long output is requested, false if not.
85 * @param user The name of the user to finger.
86 * @return The InputStream of the network connection of the finger query. Can be read to obtain finger results.
87 * @throws IOException If an I/O error during the operation.
88 */
89 public InputStream getInputStream(final boolean longOutput, final String user) throws IOException {
90 return getInputStream(longOutput, user, null);
91 }
92
93 /**
94 * Fingers a user and returns the input stream from the network connection of the finger query. You must first connect to a finger server before calling
95 * this method, and you should disconnect after finishing reading the stream.
96 *
97 * @param longOutput Set to true if long output is requested, false if not.
98 * @param user The name of the user to finger.
99 * @param encoding the character encoding that should be used for the query, null for the platform's default encoding
100 * @return The InputStream of the network connection of the finger query. Can be read to obtain finger results.
101 * @throws IOException If an I/O error during the operation.
102 */
103 public InputStream getInputStream(final boolean longOutput, final String user, final String encoding) throws IOException {
104 final DataOutputStream output;
105 final StringBuilder buffer = new StringBuilder(64);
106 if (longOutput) {
107 buffer.append(LONG_FLAG);
108 }
109 buffer.append(user);
110 buffer.append(SocketClient.NETASCII_EOL);
111
112 // Note: Charsets.toCharset() returns the platform default for null input
113 final byte[] encodedQuery = buffer.toString().getBytes(Charsets.toCharset(encoding).name()); // Java 1.6 can use
114 // charset directly
115
116 output = new DataOutputStream(new BufferedOutputStream(_output_, 1024));
117 output.write(encodedQuery, 0, encodedQuery.length);
118 output.flush();
119
120 return _input_;
121 }
122
123 /**
124 * Fingers the connected host and returns the output as a String. You must first connect to a finger server before calling this method, and you should
125 * disconnect afterward. This is equivalent to calling <code> query(longOutput, "") </code>.
126 *
127 * @param longOutput Set to true if long output is requested, false if not.
128 * @return The result of the finger query.
129 * @throws IOException If an I/O error occurs while reading the socket.
130 */
131 public String query(final boolean longOutput) throws IOException {
132 return query(longOutput, "");
133 }
134
135 /**
136 * Fingers a user at the connected host and returns the output as a String. You must first connect to a finger server before calling this method, and you
137 * should disconnect afterward.
138 *
139 * @param longOutput Set to true if long output is requested, false if not.
140 * @param user The name of the user to finger.
141 * @return The result of the finger query.
142 * @throws IOException If an I/O error occurs while reading the socket.
143 */
144 public String query(final boolean longOutput, final String user) throws IOException {
145 int read;
146 final StringBuilder result = new StringBuilder(buffer.length);
147
148 try (final BufferedReader input = new BufferedReader(new InputStreamReader(getInputStream(longOutput, user), getCharset()))) {
149 while (true) {
150 read = input.read(buffer, 0, buffer.length);
151 if (read <= 0) {
152 break;
153 }
154 result.append(buffer, 0, read);
155 }
156 }
157
158 return result.toString();
159 }
160
161 }