View Javadoc

1   /*
2    * ====================================================================
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *   http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing,
14   * software distributed under the License is distributed on an
15   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16   * KIND, either express or implied.  See the License for the
17   * specific language governing permissions and limitations
18   * under the License.
19   * ====================================================================
20   *
21   * This software consists of voluntary contributions made by many
22   * individuals on behalf of the Apache Software Foundation.  For more
23   * information on the Apache Software Foundation, please see
24   * <http://www.apache.org/>.
25   *
26   */
27  package org.apache.http.conn.scheme;
28  
29  import java.util.Locale;
30  
31  import org.apache.http.annotation.Immutable;
32  
33  import org.apache.http.util.LangUtils;
34  
35  /**
36   * Encapsulates specifics of a protocol scheme such as "http" or "https". Schemes are identified
37   * by lowercase names. Supported schemes are typically collected in a {@link SchemeRegistry
38   * SchemeRegistry}.
39   * <p/>
40   * For example, to configure support for "https://" URLs, you could write code like the following:
41   * <pre>
42   * Scheme https = new Scheme("https", 443, new MySecureSocketFactory());
43   * SchemeRegistry registry = new SchemeRegistry();
44   * registry.register(https);
45   * </pre>
46   *
47   * @since 4.0
48   */
49  @Immutable
50  public final class Scheme {
51  
52      /** The name of this scheme, in lowercase. (e.g. http, https) */
53      private final String name;
54  
55      /** The socket factory for this scheme */
56      private final SchemeSocketFactory socketFactory;
57  
58      /** The default port for this scheme */
59      private final int defaultPort;
60  
61      /** Indicates whether this scheme allows for layered connections */
62      private final boolean layered;
63  
64      /** A string representation, for {@link #toString toString}. */
65      private String stringRep;
66      /*
67       *  This is used to cache the result of the toString() method
68       *  Since the method always generates the same value, there's no
69       *  need to synchronize, and it does not affect immutability.
70      */
71  
72      /**
73       * Creates a new scheme.
74       * Whether the created scheme allows for layered connections
75       * depends on the class of <code>factory</code>.
76       *
77       * @param name      the scheme name, for example "http".
78       *                  The name will be converted to lowercase.
79       * @param port      the default port for this scheme
80       * @param factory   the factory for creating sockets for communication
81       *                  with this scheme
82       *
83       * @since 4.1
84       */
85      @SuppressWarnings("deprecation")
86      public Scheme(final String name, final int port, final SchemeSocketFactory factory) {
87          if (name == null) {
88              throw new IllegalArgumentException("Scheme name may not be null");
89          }
90          if ((port <= 0) || (port > 0xffff)) {
91              throw new IllegalArgumentException("Port is invalid: " + port);
92          }
93          if (factory == null) {
94              throw new IllegalArgumentException("Socket factory may not be null");
95          }
96          this.name = name.toLowerCase(Locale.ENGLISH);
97          this.defaultPort = port;
98          if (factory instanceof SchemeLayeredSocketFactory) {
99              this.layered = true;
100             this.socketFactory = factory;
101         } else if (factory instanceof LayeredSchemeSocketFactory) {
102             this.layered = true;
103             this.socketFactory = new SchemeLayeredSocketFactoryAdaptor2((LayeredSchemeSocketFactory) factory);
104         } else {
105             this.layered = false;
106             this.socketFactory = factory;
107         }
108     }
109 
110     /**
111      * Creates a new scheme.
112      * Whether the created scheme allows for layered connections
113      * depends on the class of <code>factory</code>.
114      *
115      * @param name      the scheme name, for example "http".
116      *                  The name will be converted to lowercase.
117      * @param factory   the factory for creating sockets for communication
118      *                  with this scheme
119      * @param port      the default port for this scheme
120      *
121      * @deprecated (4.1)  Use {@link #Scheme(String, int, SchemeSocketFactory)}
122      */
123     @Deprecated 
124     public Scheme(final String name,
125                   final SocketFactory factory,
126                   final int port) {
127 
128         if (name == null) {
129             throw new IllegalArgumentException
130                 ("Scheme name may not be null");
131         }
132         if (factory == null) {
133             throw new IllegalArgumentException
134                 ("Socket factory may not be null");
135         }
136         if ((port <= 0) || (port > 0xffff)) {
137             throw new IllegalArgumentException
138                 ("Port is invalid: " + port);
139         }
140 
141         this.name = name.toLowerCase(Locale.ENGLISH);
142         if (factory instanceof LayeredSocketFactory) {
143             this.socketFactory = new SchemeLayeredSocketFactoryAdaptor(
144                     (LayeredSocketFactory) factory);
145             this.layered = true;
146         } else {
147             this.socketFactory = new SchemeSocketFactoryAdaptor(factory);
148             this.layered = false;
149         }
150         this.defaultPort = port;
151     }
152 
153     /**
154      * Obtains the default port.
155      *
156      * @return  the default port for this scheme
157      */
158     public final int getDefaultPort() {
159         return defaultPort;
160     }
161 
162 
163     /**
164      * Obtains the socket factory.
165      * If this scheme is {@link #isLayered layered}, the factory implements
166      * {@link LayeredSocketFactory LayeredSocketFactory}.
167      *
168      * @return  the socket factory for this scheme
169      *
170      * @deprecated (4.1)  Use {@link #getSchemeSocketFactory()}
171      */
172     @Deprecated
173     public final SocketFactory getSocketFactory() {
174         if (this.socketFactory instanceof SchemeSocketFactoryAdaptor) {
175             return ((SchemeSocketFactoryAdaptor) this.socketFactory).getFactory();
176         } else {
177             if (this.layered) {
178                 return new LayeredSocketFactoryAdaptor(
179                         (LayeredSchemeSocketFactory) this.socketFactory);
180             } else {
181                 return new SocketFactoryAdaptor(this.socketFactory);
182             }
183         }
184     }
185 
186     /**
187      * Obtains the socket factory.
188      * If this scheme is {@link #isLayered layered}, the factory implements
189      * {@link LayeredSocketFactory LayeredSchemeSocketFactory}.
190      *
191      * @return  the socket factory for this scheme
192      *
193      * @since 4.1
194      */
195     public final SchemeSocketFactory getSchemeSocketFactory() {
196         return this.socketFactory;
197     }
198 
199     /**
200      * Obtains the scheme name.
201      *
202      * @return  the name of this scheme, in lowercase
203      */
204     public final String getName() {
205         return name;
206     }
207 
208     /**
209      * Indicates whether this scheme allows for layered connections.
210      *
211      * @return <code>true</code> if layered connections are possible,
212      *         <code>false</code> otherwise
213      */
214     public final boolean isLayered() {
215         return layered;
216     }
217 
218     /**
219      * Resolves the correct port for this scheme.
220      * Returns the given port if it is valid, the default port otherwise.
221      *
222      * @param port      the port to be resolved,
223      *                  a negative number to obtain the default port
224      *
225      * @return the given port or the defaultPort
226      */
227     public final int resolvePort(int port) {
228         return port <= 0 ? defaultPort : port;
229     }
230 
231     /**
232      * Return a string representation of this object.
233      *
234      * @return  a human-readable string description of this scheme
235      */
236     @Override
237     public final String toString() {
238         if (stringRep == null) {
239             StringBuilder buffer = new StringBuilder();
240             buffer.append(this.name);
241             buffer.append(':');
242             buffer.append(Integer.toString(this.defaultPort));
243             stringRep = buffer.toString();
244         }
245         return stringRep;
246     }
247 
248     @Override
249     public final boolean equals(Object obj) {
250         if (this == obj) return true;
251         if (obj instanceof Scheme) {
252             Scheme that = (Scheme) obj;
253             return this.name.equals(that.name)
254                 && this.defaultPort == that.defaultPort
255                 && this.layered == that.layered;
256         } else {
257             return false;
258         }
259     }
260 
261     @Override
262     public int hashCode() {
263         int hash = LangUtils.HASH_SEED;
264         hash = LangUtils.hashCode(hash, this.defaultPort);
265         hash = LangUtils.hashCode(hash, this.name);
266         hash = LangUtils.hashCode(hash, this.layered);
267         return hash;
268     }
269 
270 }