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1   /*
2    * Copyright (c) 1994, 2013, 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.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14   * version 2 for more details (a copy is included in the LICENSE file that
15   * accompanied this code).
16   *
17   * You should have received a copy of the GNU General Public License version
18   * 2 along with this work; if not, write to the Free Software Foundation,
19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  package sun.net;
26  
27  import java.io.*;
28  import java.net.Socket;
29  import java.net.InetAddress;
30  import java.net.InetSocketAddress;
31  import java.net.UnknownHostException;
32  import java.net.Proxy;
33  import java.util.Arrays;
34  import java.security.AccessController;
35  import java.security.PrivilegedAction;
36  
37  /**
38   * This is the base class for network clients.
39   *
40   * @author      Jonathan Payne
41   */
42  public class NetworkClient {
43      /* Default value of read timeout, if not specified (infinity) */
44      public static final int DEFAULT_READ_TIMEOUT = -1;
45  
46      /* Default value of connect timeout, if not specified (infinity) */
47      public static final int DEFAULT_CONNECT_TIMEOUT = -1;
48  
49      protected Proxy     proxy = Proxy.NO_PROXY;
50      /** Socket for communicating with server. */
51      protected Socket    serverSocket = null;
52  
53      /** Stream for printing to the server. */
54      public PrintStream  serverOutput;
55  
56      /** Buffered stream for reading replies from server. */
57      public InputStream  serverInput;
58  
59      protected static int defaultSoTimeout;
60      protected static int defaultConnectTimeout;
61  
62      protected int readTimeout = DEFAULT_READ_TIMEOUT;
63      protected int connectTimeout = DEFAULT_CONNECT_TIMEOUT;
64      /* Name of encoding to use for output */
65      protected static String encoding;
66  
67      static {
68          final int vals[] = {0, 0};
69          final String encs[] = { null };
70  
71          AccessController.doPrivileged(
72                  new PrivilegedAction<Void>() {
73                      public Void run() {
74                          vals[0] = Integer.getInteger("sun.net.client.defaultReadTimeout", 0).intValue();
75                          vals[1] = Integer.getInteger("sun.net.client.defaultConnectTimeout", 0).intValue();
76                          encs[0] = System.getProperty("file.encoding", "ISO8859_1");
77                          return null;
78              }
79          });
80          if (vals[0] != 0) {
81              defaultSoTimeout = vals[0];
82          }
83          if (vals[1] != 0) {
84              defaultConnectTimeout = vals[1];
85          }
86  
87          encoding = encs[0];
88          try {
89              if (!isASCIISuperset (encoding)) {
90                  encoding = "ISO8859_1";
91              }
92          } catch (Exception e) {
93              encoding = "ISO8859_1";
94          }
95      }
96  
97  
98      /**
99       * Test the named character encoding to verify that it converts ASCII
100      * characters correctly. We have to use an ASCII based encoding, or else
101      * the NetworkClients will not work correctly in EBCDIC based systems.
102      * However, we cannot just use ASCII or ISO8859_1 universally, because in
103      * Asian locales, non-ASCII characters may be embedded in otherwise
104      * ASCII based protocols (eg. HTTP). The specifications (RFC2616, 2398)
105      * are a little ambiguous in this matter. For instance, RFC2398 [part 2.1]
106      * says that the HTTP request URI should be escaped using a defined
107      * mechanism, but there is no way to specify in the escaped string what
108      * the original character set is. It is not correct to assume that
109      * UTF-8 is always used (as in URLs in HTML 4.0).  For this reason,
110      * until the specifications are updated to deal with this issue more
111      * comprehensively, and more importantly, HTTP servers are known to
112      * support these mechanisms, we will maintain the current behavior
113      * where it is possible to send non-ASCII characters in their original
114      * unescaped form.
115      */
116     private static boolean isASCIISuperset (String encoding) throws Exception {
117         String chkS = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"+
118                         "abcdefghijklmnopqrstuvwxyz-_.!~*'();/?:@&=+$,";
119 
120         // Expected byte sequence for string above
121         byte[] chkB = { 48,49,50,51,52,53,54,55,56,57,65,66,67,68,69,70,71,72,
122                 73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,97,98,99,
123                 100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,
124                 115,116,117,118,119,120,121,122,45,95,46,33,126,42,39,40,41,59,
125                 47,63,58,64,38,61,43,36,44};
126 
127         byte[] b = chkS.getBytes (encoding);
128         return Arrays.equals (b, chkB);
129     }
130 
131     /** Open a connection to the server. */
132     public void openServer(String server, int port)
133         throws IOException, UnknownHostException {
134         if (serverSocket != null)
135             closeServer();
136         serverSocket = doConnect (server, port);
137         try {
138             serverOutput = new PrintStream(new BufferedOutputStream(
139                                         serverSocket.getOutputStream()),
140                                         true, encoding);
141         } catch (UnsupportedEncodingException e) {
142             throw new InternalError(encoding +"encoding not found", e);
143         }
144         serverInput = new BufferedInputStream(serverSocket.getInputStream());
145     }
146 
147     /**
148      * Return a socket connected to the server, with any
149      * appropriate options pre-established
150      */
151     protected Socket doConnect (String server, int port)
152     throws IOException, UnknownHostException {
153         Socket s;
154         if (proxy != null) {
155             if (proxy.type() == Proxy.Type.SOCKS) {
156                 s = AccessController.doPrivileged(
157                     new PrivilegedAction<Socket>() {
158                         public Socket run() {
159                                        return new Socket(proxy);
160                                    }});
161             } else if (proxy.type() == Proxy.Type.DIRECT) {
162                 s = createSocket();
163             } else {
164                 // Still connecting through a proxy
165                 // server & port will be the proxy address and port
166                 s = new Socket(Proxy.NO_PROXY);
167             }
168         } else
169             s = createSocket();
170         // Instance specific timeouts do have priority, that means
171         // connectTimeout & readTimeout (-1 means not set)
172         // Then global default timeouts
173         // Then no timeout.
174         if (connectTimeout >= 0) {
175             s.connect(new InetSocketAddress(server, port), connectTimeout);
176         } else {
177             if (defaultConnectTimeout > 0) {
178                 s.connect(new InetSocketAddress(server, port), defaultConnectTimeout);
179             } else {
180                 s.connect(new InetSocketAddress(server, port));
181             }
182         }
183         if (readTimeout >= 0)
184             s.setSoTimeout(readTimeout);
185         else if (defaultSoTimeout > 0) {
186             s.setSoTimeout(defaultSoTimeout);
187         }
188         return s;
189     }
190 
191     /**
192      * The following method, createSocket, is provided to allow the
193      * https client to override it so that it may use its socket factory
194      * to create the socket.
195      */
196     protected Socket createSocket() throws IOException {
197         return new java.net.Socket();
198     }
199 
200     protected InetAddress getLocalAddress() throws IOException {
201         if (serverSocket == null)
202             throw new IOException("not connected");
203         return  AccessController.doPrivileged(
204                         new PrivilegedAction<InetAddress>() {
205                             public InetAddress run() {
206                                 return serverSocket.getLocalAddress();
207 
208                             }
209                         });
210     }
211 
212     /** Close an open connection to the server. */
213     public void closeServer() throws IOException {
214         if (! serverIsOpen()) {
215             return;
216         }
217         serverSocket.close();
218         serverSocket = null;
219         serverInput = null;
220         serverOutput = null;
221     }
222 
223     /** Return server connection status */
224     public boolean serverIsOpen() {
225         return serverSocket != null;
226     }
227 
228     /** Create connection with host <i>host</i> on port <i>port</i> */
229     public NetworkClient(String host, int port) throws IOException {
230         openServer(host, port);
231     }
232 
233     public NetworkClient() {}
234 
235     public void setConnectTimeout(int timeout) {
236         connectTimeout = timeout;
237     }
238 
239     public int getConnectTimeout() {
240         return connectTimeout;
241     }
242 
243     /**
244      * Sets the read timeout.
245      *
246      * Note: Public URLConnection (and protocol specific implementations)
247      * protect against negative timeout values being set. This implementation,
248      * and protocol specific implementations, use -1 to represent the default
249      * read timeout.
250      *
251      * This method may be invoked with the default timeout value when the
252      * protocol handler is trying to reset the timeout after doing a
253      * potentially blocking internal operation, e.g. cleaning up unread
254      * response data, buffering error stream response data, etc
255      */
256     public void setReadTimeout(int timeout) {
257         if (timeout == DEFAULT_READ_TIMEOUT)
258             timeout = defaultSoTimeout;
259 
260         if (serverSocket != null && timeout >= 0) {
261             try {
262                 serverSocket.setSoTimeout(timeout);
263             } catch(IOException e) {
264                 // We tried...
265             }
266         }
267         readTimeout = timeout;
268     }
269 
270     public int getReadTimeout() {
271         return readTimeout;
272     }
273 }