1 /*
2 * Copyright (c) 1995, 2016, 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
26 package java.net;
27
28 import java.io.IOException;
29 import java.io.InputStream;
30 import java.io.OutputStream;
31 import java.security.PrivilegedAction;
32 import java.util.Hashtable;
33 import java.util.concurrent.ConcurrentHashMap;
34 import java.util.Date;
35 import java.util.Iterator;
36 import java.util.Locale;
37 import java.util.Objects;
38 import java.util.ServiceConfigurationError;
39 import java.util.ServiceLoader;
40 import java.util.StringTokenizer;
41 import java.util.Collections;
42 import java.util.Map;
43 import java.util.List;
44 import java.security.Permission;
45 import java.security.AccessController;
46 import sun.security.util.SecurityConstants;
47 import sun.net.www.MessageHeader;
48 import sun.security.action.GetPropertyAction;
49
50 /**
51 * The abstract class {@code URLConnection} is the superclass
52 * of all classes that represent a communications link between the
53 * application and a URL. Instances of this class can be used both to
54 * read from and to write to the resource referenced by the URL. In
55 * general, creating a connection to a URL is a multistep process:
56 *
57 * <div style="text-align:center"><table style="margin:0 auto" border=2 summary="Describes the process of creating a connection to a URL: openConnection() and connect() over time.">
58 * <tr><th>{@code openConnection()}</th>
59 * <th>{@code connect()}</th></tr>
60 * <tr><td>Manipulate parameters that affect the connection to the remote
61 * resource.</td>
62 * <td>Interact with the resource; query header fields and
63 * contents.</td></tr>
64 * </table>
65 * ---------------------------->
66 * <br>time</div>
67 *
68 * <ol>
69 * <li>The connection object is created by invoking the
70 * {@code openConnection} method on a URL.
71 * <li>The setup parameters and general request properties are manipulated.
72 * <li>The actual connection to the remote object is made, using the
73 * {@code connect} method.
74 * <li>The remote object becomes available. The header fields and the contents
75 * of the remote object can be accessed.
76 * </ol>
77 * <p>
78 * The setup parameters are modified using the following methods:
79 * <ul>
80 * <li>{@code setAllowUserInteraction}
81 * <li>{@code setDoInput}
82 * <li>{@code setDoOutput}
83 * <li>{@code setIfModifiedSince}
84 * <li>{@code setUseCaches}
85 * </ul>
86 * <p>
87 * and the general request properties are modified using the method:
88 * <ul>
89 * <li>{@code setRequestProperty}
90 * </ul>
91 * <p>
92 * Default values for the {@code AllowUserInteraction} and
93 * {@code UseCaches} parameters can be set using the methods
94 * {@code setDefaultAllowUserInteraction} and
95 * {@code setDefaultUseCaches}.
96 * <p>
97 * Each of the above {@code set} methods has a corresponding
98 * {@code get} method to retrieve the value of the parameter or
99 * general request property. The specific parameters and general
100 * request properties that are applicable are protocol specific.
101 * <p>
102 * The following methods are used to access the header fields and
103 * the contents after the connection is made to the remote object:
104 * <ul>
105 * <li>{@code getContent}
106 * <li>{@code getHeaderField}
107 * <li>{@code getInputStream}
108 * <li>{@code getOutputStream}
109 * </ul>
110 * <p>
111 * Certain header fields are accessed frequently. The methods:
112 * <ul>
113 * <li>{@code getContentEncoding}
114 * <li>{@code getContentLength}
115 * <li>{@code getContentType}
116 * <li>{@code getDate}
117 * <li>{@code getExpiration}
118 * <li>{@code getLastModified}
119 * </ul>
120 * <p>
121 * provide convenient access to these fields. The
122 * {@code getContentType} method is used by the
123 * {@code getContent} method to determine the type of the remote
124 * object; subclasses may find it convenient to override the
125 * {@code getContentType} method.
126 * <p>
127 * In the common case, all of the pre-connection parameters and
128 * general request properties can be ignored: the pre-connection
129 * parameters and request properties default to sensible values. For
130 * most clients of this interface, there are only two interesting
131 * methods: {@code getInputStream} and {@code getContent},
132 * which are mirrored in the {@code URL} class by convenience methods.
133 * <p>
134 * More information on the request properties and header fields of
135 * an {@code http} connection can be found at:
136 * <blockquote><pre>
137 * <a href="http://www.ietf.org/rfc/rfc2616.txt">http://www.ietf.org/rfc/rfc2616.txt</a>
138 * </pre></blockquote>
139 *
140 * Invoking the {@code close()} methods on the {@code InputStream} or {@code OutputStream} of an
141 * {@code URLConnection} after a request may free network resources associated with this
142 * instance, unless particular protocol specifications specify different behaviours
143 * for it.
144 *
145 * @author James Gosling
146 * @see java.net.URL#openConnection()
147 * @see java.net.URLConnection#connect()
148 * @see java.net.URLConnection#getContent()
149 * @see java.net.URLConnection#getContentEncoding()
150 * @see java.net.URLConnection#getContentLength()
151 * @see java.net.URLConnection#getContentType()
152 * @see java.net.URLConnection#getDate()
153 * @see java.net.URLConnection#getExpiration()
154 * @see java.net.URLConnection#getHeaderField(int)
155 * @see java.net.URLConnection#getHeaderField(java.lang.String)
156 * @see java.net.URLConnection#getInputStream()
157 * @see java.net.URLConnection#getLastModified()
158 * @see java.net.URLConnection#getOutputStream()
159 * @see java.net.URLConnection#setAllowUserInteraction(boolean)
160 * @see java.net.URLConnection#setDefaultUseCaches(boolean)
161 * @see java.net.URLConnection#setDoInput(boolean)
162 * @see java.net.URLConnection#setDoOutput(boolean)
163 * @see java.net.URLConnection#setIfModifiedSince(long)
164 * @see java.net.URLConnection#setRequestProperty(java.lang.String, java.lang.String)
165 * @see java.net.URLConnection#setUseCaches(boolean)
166 * @since 1.0
167 */
168 public abstract class URLConnection {
169
170 /**
171 * The URL represents the remote object on the World Wide Web to
172 * which this connection is opened.
173 * <p>
174 * The value of this field can be accessed by the
175 * {@code getURL} method.
176 * <p>
177 * The default value of this variable is the value of the URL
178 * argument in the {@code URLConnection} constructor.
179 *
180 * @see java.net.URLConnection#getURL()
181 * @see java.net.URLConnection#url
182 */
183 protected URL url;
184
185 /**
186 * This variable is set by the {@code setDoInput} method. Its
187 * value is returned by the {@code getDoInput} method.
188 * <p>
189 * A URL connection can be used for input and/or output. Setting the
190 * {@code doInput} flag to {@code true} indicates that
191 * the application intends to read data from the URL connection.
192 * <p>
193 * The default value of this field is {@code true}.
194 *
195 * @see java.net.URLConnection#getDoInput()
196 * @see java.net.URLConnection#setDoInput(boolean)
197 */
198 protected boolean doInput = true;
199
200 /**
201 * This variable is set by the {@code setDoOutput} method. Its
202 * value is returned by the {@code getDoOutput} method.
203 * <p>
204 * A URL connection can be used for input and/or output. Setting the
205 * {@code doOutput} flag to {@code true} indicates
206 * that the application intends to write data to the URL connection.
207 * <p>
208 * The default value of this field is {@code false}.
209 *
210 * @see java.net.URLConnection#getDoOutput()
211 * @see java.net.URLConnection#setDoOutput(boolean)
212 */
213 protected boolean doOutput = false;
214
215 private static boolean defaultAllowUserInteraction = false;
216
217 /**
218 * If {@code true}, this {@code URL} is being examined in
219 * a context in which it makes sense to allow user interactions such
220 * as popping up an authentication dialog. If {@code false},
221 * then no user interaction is allowed.
222 * <p>
223 * The value of this field can be set by the
224 * {@code setAllowUserInteraction} method.
225 * Its value is returned by the
226 * {@code getAllowUserInteraction} method.
227 * Its default value is the value of the argument in the last invocation
228 * of the {@code setDefaultAllowUserInteraction} method.
229 *
230 * @see java.net.URLConnection#getAllowUserInteraction()
231 * @see java.net.URLConnection#setAllowUserInteraction(boolean)
232 * @see java.net.URLConnection#setDefaultAllowUserInteraction(boolean)
233 */
234 protected boolean allowUserInteraction = defaultAllowUserInteraction;
235
236 private static volatile boolean defaultUseCaches = true;
237
238 /**
239 * If {@code true}, the protocol is allowed to use caching
240 * whenever it can. If {@code false}, the protocol must always
241 * try to get a fresh copy of the object.
242 * <p>
243 * This field is set by the {@code setUseCaches} method. Its
244 * value is returned by the {@code getUseCaches} method.
245 * <p>
246 * Its default value is the value given in the last invocation of the
247 * {@code setDefaultUseCaches} method.
248 * <p>
249 * The default setting may be overridden per protocol with
250 * {@link #setDefaultUseCaches(String,boolean)}.
251 *
252 * @see java.net.URLConnection#setUseCaches(boolean)
253 * @see java.net.URLConnection#getUseCaches()
254 * @see java.net.URLConnection#setDefaultUseCaches(boolean)
255 */
256 protected boolean useCaches;
257
258 private static final ConcurrentHashMap<String,Boolean> defaultCaching =
259 new ConcurrentHashMap<>();
260
261 /**
262 * Some protocols support skipping the fetching of the object unless
263 * the object has been modified more recently than a certain time.
264 * <p>
265 * A nonzero value gives a time as the number of milliseconds since
266 * January 1, 1970, GMT. The object is fetched only if it has been
267 * modified more recently than that time.
268 * <p>
269 * This variable is set by the {@code setIfModifiedSince}
270 * method. Its value is returned by the
271 * {@code getIfModifiedSince} method.
272 * <p>
273 * The default value of this field is {@code 0}, indicating
274 * that the fetching must always occur.
275 *
276 * @see java.net.URLConnection#getIfModifiedSince()
277 * @see java.net.URLConnection#setIfModifiedSince(long)
278 */
279 protected long ifModifiedSince = 0;
280
281 /**
282 * If {@code false}, this connection object has not created a
283 * communications link to the specified URL. If {@code true},
284 * the communications link has been established.
285 */
286 protected boolean connected = false;
287
288 /**
289 * @since 1.5
290 */
291 private int connectTimeout;
292 private int readTimeout;
293
294 /**
295 * @since 1.6
296 */
297 private MessageHeader requests;
298
299 /**
300 * @since 1.1
301 */
302 private static volatile FileNameMap fileNameMap;
303
304 /**
305 * Loads filename map (a mimetable) from a data file. It will
306 * first try to load the user-specific table, defined
307 * by "content.types.user.table" property. If that fails,
308 * it tries to load the default built-in table.
309 *
310 * @return the FileNameMap
311 * @since 1.2
312 * @see #setFileNameMap(java.net.FileNameMap)
313 */
314 public static FileNameMap getFileNameMap() {
315 FileNameMap map = fileNameMap;
316
317 if (map == null) {
318 fileNameMap = map = new FileNameMap() {
319 private FileNameMap internalMap =
320 sun.net.www.MimeTable.loadTable();
321
322 public String getContentTypeFor(String fileName) {
323 return internalMap.getContentTypeFor(fileName);
324 }
325 };
326 }
327
328 return map;
329 }
330
331 /**
332 * Sets the FileNameMap.
333 * <p>
334 * If there is a security manager, this method first calls
335 * the security manager's {@code checkSetFactory} method
336 * to ensure the operation is allowed.
337 * This could result in a SecurityException.
338 *
339 * @param map the FileNameMap to be set
340 * @exception SecurityException if a security manager exists and its
341 * {@code checkSetFactory} method doesn't allow the operation.
342 * @see SecurityManager#checkSetFactory
343 * @see #getFileNameMap()
344 * @since 1.2
345 */
346 public static void setFileNameMap(FileNameMap map) {
347 SecurityManager sm = System.getSecurityManager();
348 if (sm != null) sm.checkSetFactory();
349 fileNameMap = map;
350 }
351
352 /**
353 * Opens a communications link to the resource referenced by this
354 * URL, if such a connection has not already been established.
355 * <p>
356 * If the {@code connect} method is called when the connection
357 * has already been opened (indicated by the {@code connected}
358 * field having the value {@code true}), the call is ignored.
359 * <p>
360 * URLConnection objects go through two phases: first they are
361 * created, then they are connected. After being created, and
362 * before being connected, various options can be specified
363 * (e.g., doInput and UseCaches). After connecting, it is an
364 * error to try to set them. Operations that depend on being
365 * connected, like getContentLength, will implicitly perform the
366 * connection, if necessary.
367 *
368 * @throws SocketTimeoutException if the timeout expires before
369 * the connection can be established
370 * @exception IOException if an I/O error occurs while opening the
371 * connection.
372 * @see java.net.URLConnection#connected
373 * @see #getConnectTimeout()
374 * @see #setConnectTimeout(int)
375 */
376 public abstract void connect() throws IOException;
377
378 /**
379 * Sets a specified timeout value, in milliseconds, to be used
380 * when opening a communications link to the resource referenced
381 * by this URLConnection. If the timeout expires before the
382 * connection can be established, a
383 * java.net.SocketTimeoutException is raised. A timeout of zero is
384 * interpreted as an infinite timeout.
385
386 * <p> Some non-standard implementation of this method may ignore
387 * the specified timeout. To see the connect timeout set, please
388 * call getConnectTimeout().
389 *
390 * @param timeout an {@code int} that specifies the connect
391 * timeout value in milliseconds
392 * @throws IllegalArgumentException if the timeout parameter is negative
393 *
394 * @see #getConnectTimeout()
395 * @see #connect()
396 * @since 1.5
397 */
398 public void setConnectTimeout(int timeout) {
399 if (timeout < 0) {
400 throw new IllegalArgumentException("timeout can not be negative");
401 }
402 connectTimeout = timeout;
403 }
404
405 /**
406 * Returns setting for connect timeout.
407 * <p>
408 * 0 return implies that the option is disabled
409 * (i.e., timeout of infinity).
410 *
411 * @return an {@code int} that indicates the connect timeout
412 * value in milliseconds
413 * @see #setConnectTimeout(int)
414 * @see #connect()
415 * @since 1.5
416 */
417 public int getConnectTimeout() {
418 return connectTimeout;
419 }
420
421 /**
422 * Sets the read timeout to a specified timeout, in
423 * milliseconds. A non-zero value specifies the timeout when
424 * reading from Input stream when a connection is established to a
425 * resource. If the timeout expires before there is data available
426 * for read, a java.net.SocketTimeoutException is raised. A
427 * timeout of zero is interpreted as an infinite timeout.
428 *
429 *<p> Some non-standard implementation of this method ignores the
430 * specified timeout. To see the read timeout set, please call
431 * getReadTimeout().
432 *
433 * @param timeout an {@code int} that specifies the timeout
434 * value to be used in milliseconds
435 * @throws IllegalArgumentException if the timeout parameter is negative
436 *
437 * @see #getReadTimeout()
438 * @see InputStream#read()
439 * @since 1.5
440 */
441 public void setReadTimeout(int timeout) {
442 if (timeout < 0) {
443 throw new IllegalArgumentException("timeout can not be negative");
444 }
445 readTimeout = timeout;
446 }
447
448 /**
449 * Returns setting for read timeout. 0 return implies that the
450 * option is disabled (i.e., timeout of infinity).
451 *
452 * @return an {@code int} that indicates the read timeout
453 * value in milliseconds
454 *
455 * @see #setReadTimeout(int)
456 * @see InputStream#read()
457 * @since 1.5
458 */
459 public int getReadTimeout() {
460 return readTimeout;
461 }
462
463 /**
464 * Constructs a URL connection to the specified URL. A connection to
465 * the object referenced by the URL is not created.
466 *
467 * @param url the specified URL.
468 */
469 protected URLConnection(URL url) {
470 this.url = url;
471 if (url == null) {
472 this.useCaches = defaultUseCaches;
473 } else {
474 this.useCaches = getDefaultUseCaches(url.getProtocol());
475 }
476 }
477
478 /**
479 * Returns the value of this {@code URLConnection}'s {@code URL}
480 * field.
481 *
482 * @return the value of this {@code URLConnection}'s {@code URL}
483 * field.
484 * @see java.net.URLConnection#url
485 */
486 public URL getURL() {
487 return url;
488 }
489
490 /**
491 * Returns the value of the {@code content-length} header field.
492 * <P>
493 * <B>Note</B>: {@link #getContentLengthLong() getContentLengthLong()}
494 * should be preferred over this method, since it returns a {@code long}
495 * instead and is therefore more portable.</P>
496 *
497 * @return the content length of the resource that this connection's URL
498 * references, {@code -1} if the content length is not known,
499 * or if the content length is greater than Integer.MAX_VALUE.
500 */
501 public int getContentLength() {
502 long l = getContentLengthLong();
503 if (l > Integer.MAX_VALUE)
504 return -1;
505 return (int) l;
506 }
507
508 /**
509 * Returns the value of the {@code content-length} header field as a
510 * long.
511 *
512 * @return the content length of the resource that this connection's URL
513 * references, or {@code -1} if the content length is
514 * not known.
515 * @since 1.7
516 */
517 public long getContentLengthLong() {
518 return getHeaderFieldLong("content-length", -1);
519 }
520
521 /**
522 * Returns the value of the {@code content-type} header field.
523 *
524 * @return the content type of the resource that the URL references,
525 * or {@code null} if not known.
526 * @see java.net.URLConnection#getHeaderField(java.lang.String)
527 */
528 public String getContentType() {
529 return getHeaderField("content-type");
530 }
531
532 /**
533 * Returns the value of the {@code content-encoding} header field.
534 *
535 * @return the content encoding of the resource that the URL references,
536 * or {@code null} if not known.
537 * @see java.net.URLConnection#getHeaderField(java.lang.String)
538 */
539 public String getContentEncoding() {
540 return getHeaderField("content-encoding");
541 }
542
543 /**
544 * Returns the value of the {@code expires} header field.
545 *
546 * @return the expiration date of the resource that this URL references,
547 * or 0 if not known. The value is the number of milliseconds since
548 * January 1, 1970 GMT.
549 * @see java.net.URLConnection#getHeaderField(java.lang.String)
550 */
551 public long getExpiration() {
552 return getHeaderFieldDate("expires", 0);
553 }
554
555 /**
556 * Returns the value of the {@code date} header field.
557 *
558 * @return the sending date of the resource that the URL references,
559 * or {@code 0} if not known. The value returned is the
560 * number of milliseconds since January 1, 1970 GMT.
561 * @see java.net.URLConnection#getHeaderField(java.lang.String)
562 */
563 public long getDate() {
564 return getHeaderFieldDate("date", 0);
565 }
566
567 /**
568 * Returns the value of the {@code last-modified} header field.
569 * The result is the number of milliseconds since January 1, 1970 GMT.
570 *
571 * @return the date the resource referenced by this
572 * {@code URLConnection} was last modified, or 0 if not known.
573 * @see java.net.URLConnection#getHeaderField(java.lang.String)
574 */
575 public long getLastModified() {
576 return getHeaderFieldDate("last-modified", 0);
577 }
578
579 /**
580 * Returns the value of the named header field.
581 * <p>
582 * If called on a connection that sets the same header multiple times
583 * with possibly different values, only the last value is returned.
584 *
585 *
586 * @param name the name of a header field.
587 * @return the value of the named header field, or {@code null}
588 * if there is no such field in the header.
589 */
590 public String getHeaderField(String name) {
591 return null;
592 }
593
594 /**
595 * Returns an unmodifiable Map of the header fields.
596 * The Map keys are Strings that represent the
597 * response-header field names. Each Map value is an
598 * unmodifiable List of Strings that represents
599 * the corresponding field values.
600 *
601 * @return a Map of header fields
602 * @since 1.4
603 */
604 public Map<String,List<String>> getHeaderFields() {
605 return Collections.emptyMap();
606 }
607
608 /**
609 * Returns the value of the named field parsed as a number.
610 * <p>
611 * This form of {@code getHeaderField} exists because some
612 * connection types (e.g., {@code http-ng}) have pre-parsed
613 * headers. Classes for that connection type can override this method
614 * and short-circuit the parsing.
615 *
616 * @param name the name of the header field.
617 * @param Default the default value.
618 * @return the value of the named field, parsed as an integer. The
619 * {@code Default} value is returned if the field is
620 * missing or malformed.
621 */
622 public int getHeaderFieldInt(String name, int Default) {
623 String value = getHeaderField(name);
624 try {
625 return Integer.parseInt(value);
626 } catch (Exception e) { }
627 return Default;
628 }
629
630 /**
631 * Returns the value of the named field parsed as a number.
632 * <p>
633 * This form of {@code getHeaderField} exists because some
634 * connection types (e.g., {@code http-ng}) have pre-parsed
635 * headers. Classes for that connection type can override this method
636 * and short-circuit the parsing.
637 *
638 * @param name the name of the header field.
639 * @param Default the default value.
640 * @return the value of the named field, parsed as a long. The
641 * {@code Default} value is returned if the field is
642 * missing or malformed.
643 * @since 1.7
644 */
645 public long getHeaderFieldLong(String name, long Default) {
646 String value = getHeaderField(name);
647 try {
648 return Long.parseLong(value);
649 } catch (Exception e) { }
650 return Default;
651 }
652
653 /**
654 * Returns the value of the named field parsed as date.
655 * The result is the number of milliseconds since January 1, 1970 GMT
656 * represented by the named field.
657 * <p>
658 * This form of {@code getHeaderField} exists because some
659 * connection types (e.g., {@code http-ng}) have pre-parsed
660 * headers. Classes for that connection type can override this method
661 * and short-circuit the parsing.
662 *
663 * @param name the name of the header field.
664 * @param Default a default value.
665 * @return the value of the field, parsed as a date. The value of the
666 * {@code Default} argument is returned if the field is
667 * missing or malformed.
668 */
669 @SuppressWarnings("deprecation")
670 public long getHeaderFieldDate(String name, long Default) {
671 String value = getHeaderField(name);
672 try {
673 return Date.parse(value);
674 } catch (Exception e) { }
675 return Default;
676 }
677
678 /**
679 * Returns the key for the {@code n}<sup>th</sup> header field.
680 * It returns {@code null} if there are fewer than {@code n+1} fields.
681 *
682 * @param n an index, where {@code n>=0}
683 * @return the key for the {@code n}<sup>th</sup> header field,
684 * or {@code null} if there are fewer than {@code n+1}
685 * fields.
686 */
687 public String getHeaderFieldKey(int n) {
688 return null;
689 }
690
691 /**
692 * Returns the value for the {@code n}<sup>th</sup> header field.
693 * It returns {@code null} if there are fewer than
694 * {@code n+1}fields.
695 * <p>
696 * This method can be used in conjunction with the
697 * {@link #getHeaderFieldKey(int) getHeaderFieldKey} method to iterate through all
698 * the headers in the message.
699 *
700 * @param n an index, where {@code n>=0}
701 * @return the value of the {@code n}<sup>th</sup> header field
702 * or {@code null} if there are fewer than {@code n+1} fields
703 * @see java.net.URLConnection#getHeaderFieldKey(int)
704 */
705 public String getHeaderField(int n) {
706 return null;
707 }
708
709 /**
710 * Retrieves the contents of this URL connection.
711 * <p>
712 * This method first determines the content type of the object by
713 * calling the {@code getContentType} method. If this is
714 * the first time that the application has seen that specific content
715 * type, a content handler for that content type is created.
716 * <p> This is done as follows:
717 * <ol>
718 * <li>If the application has set up a content handler factory instance
719 * using the {@code setContentHandlerFactory} method, the
720 * {@code createContentHandler} method of that instance is called
721 * with the content type as an argument; the result is a content
722 * handler for that content type.
723 * <li>If no {@code ContentHandlerFactory} has yet been set up,
724 * or if the factory's {@code createContentHandler} method
725 * returns {@code null}, then the {@linkplain java.util.ServiceLoader
726 * ServiceLoader} mechanism is used to locate {@linkplain
727 * java.net.ContentHandlerFactory ContentHandlerFactory}
728 * implementations using the system class
729 * loader. The order that factories are located is implementation
730 * specific, and an implementation is free to cache the located
731 * factories. A {@linkplain java.util.ServiceConfigurationError
732 * ServiceConfigurationError}, {@code Error} or {@code RuntimeException}
733 * thrown from the {@code createContentHandler}, if encountered, will
734 * be propagated to the calling thread. The {@code
735 * createContentHandler} method of each factory, if instantiated, is
736 * invoked, with the content type, until a factory returns non-null,
737 * or all factories have been exhausted.
738 * <li>Failing that, this method tries to load a content handler
739 * class as defined by {@link java.net.ContentHandler ContentHandler}.
740 * If the class does not exist, or is not a subclass of {@code
741 * ContentHandler}, then an {@code UnknownServiceException} is thrown.
742 * </ol>
743 *
744 * @return the object fetched. The {@code instanceof} operator
745 * should be used to determine the specific kind of object
746 * returned.
747 * @exception IOException if an I/O error occurs while
748 * getting the content.
749 * @exception UnknownServiceException if the protocol does not support
750 * the content type.
751 * @see java.net.ContentHandlerFactory#createContentHandler(java.lang.String)
752 * @see java.net.URLConnection#getContentType()
753 * @see java.net.URLConnection#setContentHandlerFactory(java.net.ContentHandlerFactory)
754 */
755 public Object getContent() throws IOException {
756 // Must call getInputStream before GetHeaderField gets called
757 // so that FileNotFoundException has a chance to be thrown up
758 // from here without being caught.
759 getInputStream();
760 return getContentHandler().getContent(this);
761 }
762
763 /**
764 * Retrieves the contents of this URL connection.
765 *
766 * @param classes the {@code Class} array
767 * indicating the requested types
768 * @return the object fetched that is the first match of the type
769 * specified in the classes array. null if none of
770 * the requested types are supported.
771 * The {@code instanceof} operator should be used to
772 * determine the specific kind of object returned.
773 * @exception IOException if an I/O error occurs while
774 * getting the content.
775 * @exception UnknownServiceException if the protocol does not support
776 * the content type.
777 * @see java.net.URLConnection#getContent()
778 * @see java.net.ContentHandlerFactory#createContentHandler(java.lang.String)
779 * @see java.net.URLConnection#getContent(java.lang.Class[])
780 * @see java.net.URLConnection#setContentHandlerFactory(java.net.ContentHandlerFactory)
781 * @since 1.3
782 */
783 public Object getContent(Class<?>[] classes) throws IOException {
784 // Must call getInputStream before GetHeaderField gets called
785 // so that FileNotFoundException has a chance to be thrown up
786 // from here without being caught.
787 getInputStream();
788 return getContentHandler().getContent(this, classes);
789 }
790
791 /**
792 * Returns a permission object representing the permission
793 * necessary to make the connection represented by this
794 * object. This method returns null if no permission is
795 * required to make the connection. By default, this method
796 * returns {@code java.security.AllPermission}. Subclasses
797 * should override this method and return the permission
798 * that best represents the permission required to make a
799 * a connection to the URL. For example, a {@code URLConnection}
800 * representing a {@code file:} URL would return a
801 * {@code java.io.FilePermission} object.
802 *
803 * <p>The permission returned may dependent upon the state of the
804 * connection. For example, the permission before connecting may be
805 * different from that after connecting. For example, an HTTP
806 * sever, say foo.com, may redirect the connection to a different
807 * host, say bar.com. Before connecting the permission returned by
808 * the connection will represent the permission needed to connect
809 * to foo.com, while the permission returned after connecting will
810 * be to bar.com.
811 *
812 * <p>Permissions are generally used for two purposes: to protect
813 * caches of objects obtained through URLConnections, and to check
814 * the right of a recipient to learn about a particular URL. In
815 * the first case, the permission should be obtained
816 * <em>after</em> the object has been obtained. For example, in an
817 * HTTP connection, this will represent the permission to connect
818 * to the host from which the data was ultimately fetched. In the
819 * second case, the permission should be obtained and tested
820 * <em>before</em> connecting.
821 *
822 * @return the permission object representing the permission
823 * necessary to make the connection represented by this
824 * URLConnection.
825 *
826 * @exception IOException if the computation of the permission
827 * requires network or file I/O and an exception occurs while
828 * computing it.
829 */
830 public Permission getPermission() throws IOException {
831 return SecurityConstants.ALL_PERMISSION;
832 }
833
834 /**
835 * Returns an input stream that reads from this open connection.
836 *
837 * A SocketTimeoutException can be thrown when reading from the
838 * returned input stream if the read timeout expires before data
839 * is available for read.
840 *
841 * @return an input stream that reads from this open connection.
842 * @exception IOException if an I/O error occurs while
843 * creating the input stream.
844 * @exception UnknownServiceException if the protocol does not support
845 * input.
846 * @see #setReadTimeout(int)
847 * @see #getReadTimeout()
848 */
849 public InputStream getInputStream() throws IOException {
850 throw new UnknownServiceException("protocol doesn't support input");
851 }
852
853 /**
854 * Returns an output stream that writes to this connection.
855 *
856 * @return an output stream that writes to this connection.
857 * @exception IOException if an I/O error occurs while
858 * creating the output stream.
859 * @exception UnknownServiceException if the protocol does not support
860 * output.
861 */
862 public OutputStream getOutputStream() throws IOException {
863 throw new UnknownServiceException("protocol doesn't support output");
864 }
865
866 /**
867 * Returns a {@code String} representation of this URL connection.
868 *
869 * @return a string representation of this {@code URLConnection}.
870 */
871 public String toString() {
872 return this.getClass().getName() + ":" + url;
873 }
874
875 /**
876 * Sets the value of the {@code doInput} field for this
877 * {@code URLConnection} to the specified value.
878 * <p>
879 * A URL connection can be used for input and/or output. Set the DoInput
880 * flag to true if you intend to use the URL connection for input,
881 * false if not. The default is true.
882 *
883 * @param doinput the new value.
884 * @throws IllegalStateException if already connected
885 * @see java.net.URLConnection#doInput
886 * @see #getDoInput()
887 */
888 public void setDoInput(boolean doinput) {
889 checkConnected();
890 doInput = doinput;
891 }
892
893 /**
894 * Returns the value of this {@code URLConnection}'s
895 * {@code doInput} flag.
896 *
897 * @return the value of this {@code URLConnection}'s
898 * {@code doInput} flag.
899 * @see #setDoInput(boolean)
900 */
901 public boolean getDoInput() {
902 return doInput;
903 }
904
905 /**
906 * Sets the value of the {@code doOutput} field for this
907 * {@code URLConnection} to the specified value.
908 * <p>
909 * A URL connection can be used for input and/or output. Set the DoOutput
910 * flag to true if you intend to use the URL connection for output,
911 * false if not. The default is false.
912 *
913 * @param dooutput the new value.
914 * @throws IllegalStateException if already connected
915 * @see #getDoOutput()
916 */
917 public void setDoOutput(boolean dooutput) {
918 checkConnected();
919 doOutput = dooutput;
920 }
921
922 /**
923 * Returns the value of this {@code URLConnection}'s
924 * {@code doOutput} flag.
925 *
926 * @return the value of this {@code URLConnection}'s
927 * {@code doOutput} flag.
928 * @see #setDoOutput(boolean)
929 */
930 public boolean getDoOutput() {
931 return doOutput;
932 }
933
934 /**
935 * Set the value of the {@code allowUserInteraction} field of
936 * this {@code URLConnection}.
937 *
938 * @param allowuserinteraction the new value.
939 * @throws IllegalStateException if already connected
940 * @see #getAllowUserInteraction()
941 */
942 public void setAllowUserInteraction(boolean allowuserinteraction) {
943 checkConnected();
944 allowUserInteraction = allowuserinteraction;
945 }
946
947 /**
948 * Returns the value of the {@code allowUserInteraction} field for
949 * this object.
950 *
951 * @return the value of the {@code allowUserInteraction} field for
952 * this object.
953 * @see #setAllowUserInteraction(boolean)
954 */
955 public boolean getAllowUserInteraction() {
956 return allowUserInteraction;
957 }
958
959 /**
960 * Sets the default value of the
961 * {@code allowUserInteraction} field for all future
962 * {@code URLConnection} objects to the specified value.
963 *
964 * @param defaultallowuserinteraction the new value.
965 * @see #getDefaultAllowUserInteraction()
966 */
967 public static void setDefaultAllowUserInteraction(boolean defaultallowuserinteraction) {
968 defaultAllowUserInteraction = defaultallowuserinteraction;
969 }
970
971 /**
972 * Returns the default value of the {@code allowUserInteraction}
973 * field.
974 * <p>
975 * Ths default is "sticky", being a part of the static state of all
976 * URLConnections. This flag applies to the next, and all following
977 * URLConnections that are created.
978 *
979 * @return the default value of the {@code allowUserInteraction}
980 * field.
981 * @see #setDefaultAllowUserInteraction(boolean)
982 */
983 public static boolean getDefaultAllowUserInteraction() {
984 return defaultAllowUserInteraction;
985 }
986
987 /**
988 * Sets the value of the {@code useCaches} field of this
989 * {@code URLConnection} to the specified value.
990 * <p>
991 * Some protocols do caching of documents. Occasionally, it is important
992 * to be able to "tunnel through" and ignore the caches (e.g., the
993 * "reload" button in a browser). If the UseCaches flag on a connection
994 * is true, the connection is allowed to use whatever caches it can.
995 * If false, caches are to be ignored.
996 * The default value comes from DefaultUseCaches, which defaults to
997 * true. A default value can also be set per-protocol using
998 * {@link #setDefaultUseCaches(String,boolean)}.
999 *
1000 * @param usecaches a {@code boolean} indicating whether
1001 * or not to allow caching
1002 * @throws IllegalStateException if already connected
1003 * @see #getUseCaches()
1004 */
1005 public void setUseCaches(boolean usecaches) {
1006 checkConnected();
1007 useCaches = usecaches;
1008 }
1009
1010 /**
1011 * Returns the value of this {@code URLConnection}'s
1012 * {@code useCaches} field.
1013 *
1014 * @return the value of this {@code URLConnection}'s
1015 * {@code useCaches} field.
1016 * @see #setUseCaches(boolean)
1017 */
1018 public boolean getUseCaches() {
1019 return useCaches;
1020 }
1021
1022 /**
1023 * Sets the value of the {@code ifModifiedSince} field of
1024 * this {@code URLConnection} to the specified value.
1025 *
1026 * @param ifmodifiedsince the new value.
1027 * @throws IllegalStateException if already connected
1028 * @see #getIfModifiedSince()
1029 */
1030 public void setIfModifiedSince(long ifmodifiedsince) {
1031 checkConnected();
1032 ifModifiedSince = ifmodifiedsince;
1033 }
1034
1035 /**
1036 * Returns the value of this object's {@code ifModifiedSince} field.
1037 *
1038 * @return the value of this object's {@code ifModifiedSince} field.
1039 * @see #setIfModifiedSince(long)
1040 */
1041 public long getIfModifiedSince() {
1042 return ifModifiedSince;
1043 }
1044
1045 /**
1046 * Returns the default value of a {@code URLConnection}'s
1047 * {@code useCaches} flag.
1048 * <p>
1049 * This default is "sticky", being a part of the static state of all
1050 * URLConnections. This flag applies to the next, and all following
1051 * URLConnections that are created. This default value can be over-ridden
1052 * per protocol using {@link #setDefaultUseCaches(String,boolean)}
1053 *
1054 * @return the default value of a {@code URLConnection}'s
1055 * {@code useCaches} flag.
1056 * @see #setDefaultUseCaches(boolean)
1057 */
1058 public boolean getDefaultUseCaches() {
1059 return defaultUseCaches;
1060 }
1061
1062 /**
1063 * Sets the default value of the {@code useCaches} field to the
1064 * specified value. This default value can be over-ridden
1065 * per protocol using {@link #setDefaultUseCaches(String,boolean)}
1066 *
1067 * @param defaultusecaches the new value.
1068 * @see #getDefaultUseCaches()
1069 */
1070 public void setDefaultUseCaches(boolean defaultusecaches) {
1071 defaultUseCaches = defaultusecaches;
1072 }
1073
1074 /**
1075 * Sets the default value of the {@code useCaches} field for the named
1076 * protocol to the given value. This value overrides any default setting
1077 * set by {@link #setDefaultUseCaches(boolean)} for the given protocol.
1078 * Successive calls to this method change the setting and affect the
1079 * default value for all future connections of that protocol. The protocol
1080 * name is case insensitive.
1081 *
1082 * @param protocol the protocol to set the default for
1083 * @param defaultVal whether caching is enabled by default for the given protocol
1084 * @since 9
1085 */
1086 public static void setDefaultUseCaches(String protocol, boolean defaultVal) {
1087 protocol = protocol.toLowerCase(Locale.US);
1088 defaultCaching.put(protocol, defaultVal);
1089 }
1090
1091 /**
1092 * Returns the default value of the {@code useCaches} flag for the given protocol. If
1093 * {@link #setDefaultUseCaches(String,boolean)} was called for the given protocol,
1094 * then that value is returned. Otherwise, if {@link #setDefaultUseCaches(boolean)}
1095 * was called, then that value is returned. If neither method was called,
1096 * the return value is {@code true}. The protocol name is case insensitive.
1097 *
1098 * @param protocol the protocol whose defaultUseCaches setting is required
1099 * @return the default value of the {@code useCaches} flag for the given protocol.
1100 * @since 9
1101 */
1102 public static boolean getDefaultUseCaches(String protocol) {
1103 Boolean protoDefault = defaultCaching.get(protocol.toLowerCase(Locale.US));
1104 if (protoDefault != null) {
1105 return protoDefault.booleanValue();
1106 } else {
1107 return defaultUseCaches;
1108 }
1109 }
1110
1111 /**
1112 * Sets the general request property. If a property with the key already
1113 * exists, overwrite its value with the new value.
1114 *
1115 * <p> NOTE: HTTP requires all request properties which can
1116 * legally have multiple instances with the same key
1117 * to use a comma-separated list syntax which enables multiple
1118 * properties to be appended into a single property.
1119 *
1120 * @param key the keyword by which the request is known
1121 * (e.g., "{@code Accept}").
1122 * @param value the value associated with it.
1123 * @throws IllegalStateException if already connected
1124 * @throws NullPointerException if key is {@code null}
1125 * @see #getRequestProperty(java.lang.String)
1126 */
1127 public void setRequestProperty(String key, String value) {
1128 checkConnected();
1129 if (key == null)
1130 throw new NullPointerException ("key is null");
1131
1132 if (requests == null)
1133 requests = new MessageHeader();
1134
1135 requests.set(key, value);
1136 }
1137
1138 /**
1139 * Adds a general request property specified by a
1140 * key-value pair. This method will not overwrite
1141 * existing values associated with the same key.
1142 *
1143 * @param key the keyword by which the request is known
1144 * (e.g., "{@code Accept}").
1145 * @param value the value associated with it.
1146 * @throws IllegalStateException if already connected
1147 * @throws NullPointerException if key is null
1148 * @see #getRequestProperties()
1149 * @since 1.4
1150 */
1151 public void addRequestProperty(String key, String value) {
1152 checkConnected();
1153 if (key == null)
1154 throw new NullPointerException ("key is null");
1155
1156 if (requests == null)
1157 requests = new MessageHeader();
1158
1159 requests.add(key, value);
1160 }
1161
1162
1163 /**
1164 * Returns the value of the named general request property for this
1165 * connection.
1166 *
1167 * @param key the keyword by which the request is known (e.g., "Accept").
1168 * @return the value of the named general request property for this
1169 * connection. If key is null, then null is returned.
1170 * @throws IllegalStateException if already connected
1171 * @see #setRequestProperty(java.lang.String, java.lang.String)
1172 */
1173 public String getRequestProperty(String key) {
1174 checkConnected();
1175
1176 if (requests == null)
1177 return null;
1178
1179 return requests.findValue(key);
1180 }
1181
1182 /**
1183 * Returns an unmodifiable Map of general request
1184 * properties for this connection. The Map keys
1185 * are Strings that represent the request-header
1186 * field names. Each Map value is a unmodifiable List
1187 * of Strings that represents the corresponding
1188 * field values.
1189 *
1190 * @return a Map of the general request properties for this connection.
1191 * @throws IllegalStateException if already connected
1192 * @since 1.4
1193 */
1194 public Map<String,List<String>> getRequestProperties() {
1195 checkConnected();
1196
1197 if (requests == null)
1198 return Collections.emptyMap();
1199
1200 return requests.getHeaders(null);
1201 }
1202
1203 /**
1204 * Sets the default value of a general request property. When a
1205 * {@code URLConnection} is created, it is initialized with
1206 * these properties.
1207 *
1208 * @param key the keyword by which the request is known
1209 * (e.g., "{@code Accept}").
1210 * @param value the value associated with the key.
1211 *
1212 * @see java.net.URLConnection#setRequestProperty(java.lang.String,java.lang.String)
1213 *
1214 * @deprecated The instance specific setRequestProperty method
1215 * should be used after an appropriate instance of URLConnection
1216 * is obtained. Invoking this method will have no effect.
1217 *
1218 * @see #getDefaultRequestProperty(java.lang.String)
1219 */
1220 @Deprecated
1221 public static void setDefaultRequestProperty(String key, String value) {
1222 }
1223
1224 /**
1225 * Returns the value of the default request property. Default request
1226 * properties are set for every connection.
1227 *
1228 * @param key the keyword by which the request is known (e.g., "Accept").
1229 * @return the value of the default request property
1230 * for the specified key.
1231 *
1232 * @see java.net.URLConnection#getRequestProperty(java.lang.String)
1233 *
1234 * @deprecated The instance specific getRequestProperty method
1235 * should be used after an appropriate instance of URLConnection
1236 * is obtained.
1237 *
1238 * @see #setDefaultRequestProperty(java.lang.String, java.lang.String)
1239 */
1240 @Deprecated
1241 public static String getDefaultRequestProperty(String key) {
1242 return null;
1243 }
1244
1245 /**
1246 * The ContentHandler factory.
1247 */
1248 private static volatile ContentHandlerFactory factory;
1249
1250 /**
1251 * Sets the {@code ContentHandlerFactory} of an
1252 * application. It can be called at most once by an application.
1253 * <p>
1254 * The {@code ContentHandlerFactory} instance is used to
1255 * construct a content handler from a content type
1256 * <p>
1257 * If there is a security manager, this method first calls
1258 * the security manager's {@code checkSetFactory} method
1259 * to ensure the operation is allowed.
1260 * This could result in a SecurityException.
1261 *
1262 * @param fac the desired factory.
1263 * @exception Error if the factory has already been defined.
1264 * @exception SecurityException if a security manager exists and its
1265 * {@code checkSetFactory} method doesn't allow the operation.
1266 * @see java.net.ContentHandlerFactory
1267 * @see java.net.URLConnection#getContent()
1268 * @see SecurityManager#checkSetFactory
1269 */
1270 public static synchronized void setContentHandlerFactory(ContentHandlerFactory fac) {
1271 if (factory != null) {
1272 throw new Error("factory already defined");
1273 }
1274 SecurityManager security = System.getSecurityManager();
1275 if (security != null) {
1276 security.checkSetFactory();
1277 }
1278 factory = fac;
1279 }
1280
1281 private static final Hashtable<String, ContentHandler> handlers = new Hashtable<>();
1282
1283 /**
1284 * Gets the Content Handler appropriate for this connection.
1285 */
1286 private ContentHandler getContentHandler() throws UnknownServiceException {
1287 String contentType = stripOffParameters(getContentType());
1288 if (contentType == null) {
1289 throw new UnknownServiceException("no content-type");
1290 }
1291
1292 ContentHandler handler = handlers.get(contentType);
1293 if (handler != null)
1294 return handler;
1295
1296 if (factory != null) {
1297 handler = factory.createContentHandler(contentType);
1298 if (handler != null)
1299 return handler;
1300 }
1301
1302 handler = lookupContentHandlerViaProvider(contentType);
1303
1304 if (handler != null) {
1305 ContentHandler h = handlers.putIfAbsent(contentType, handler);
1306 return Objects.requireNonNullElse(h, handler);
1307 }
1308
1309 try {
1310 handler = lookupContentHandlerClassFor(contentType);
1311 } catch (Exception e) {
1312 e.printStackTrace();
1313 handler = UnknownContentHandler.INSTANCE;
1314 }
1315
1316 assert handler != null;
1317
1318 ContentHandler h = handlers.putIfAbsent(contentType, handler);
1319 return Objects.requireNonNullElse(h, handler);
1320 }
1321
1322 /*
1323 * Media types are in the format: type/subtype*(; parameter).
1324 * For looking up the content handler, we should ignore those
1325 * parameters.
1326 */
1327 private String stripOffParameters(String contentType)
1328 {
1329 if (contentType == null)
1330 return null;
1331 int index = contentType.indexOf(';');
1332
1333 if (index > 0)
1334 return contentType.substring(0, index);
1335 else
1336 return contentType;
1337 }
1338
1339 private static final String contentClassPrefix = "sun.net.www.content";
1340 private static final String contentPathProp = "java.content.handler.pkgs";
1341
1342 /**
1343 * Looks for a content handler in a user-definable set of places.
1344 * By default it looks in {@value #contentClassPrefix}, but users can define
1345 * a vertical-bar delimited set of class prefixes to search through in
1346 * addition by defining the {@value #contentPathProp} property.
1347 * The class name must be of the form:
1348 * <pre>
1349 * {package-prefix}.{major}.{minor}
1350 * e.g.
1351 * YoyoDyne.experimental.text.plain
1352 * </pre>
1353 */
1354 private ContentHandler lookupContentHandlerClassFor(String contentType) {
1355 String contentHandlerClassName = typeToPackageName(contentType);
1356
1357 String contentHandlerPkgPrefixes = getContentHandlerPkgPrefixes();
1358
1359 StringTokenizer packagePrefixIter =
1360 new StringTokenizer(contentHandlerPkgPrefixes, "|");
1361
1362 while (packagePrefixIter.hasMoreTokens()) {
1363 String packagePrefix = packagePrefixIter.nextToken().trim();
1364
1365 try {
1366 String clsName = packagePrefix + "." + contentHandlerClassName;
1367 Class<?> cls = null;
1368 try {
1369 cls = Class.forName(clsName);
1370 } catch (ClassNotFoundException e) {
1371 ClassLoader cl = ClassLoader.getSystemClassLoader();
1372 if (cl != null) {
1373 cls = cl.loadClass(clsName);
1374 }
1375 }
1376 if (cls != null) {
1377 @SuppressWarnings("deprecation")
1378 Object tmp = cls.newInstance();
1379 return (ContentHandler) tmp;
1380 }
1381 } catch(Exception ignored) { }
1382 }
1383
1384 return UnknownContentHandler.INSTANCE;
1385 }
1386
1387 private ContentHandler lookupContentHandlerViaProvider(String contentType) {
1388 return AccessController.doPrivileged(
1389 new PrivilegedAction<>() {
1390 @Override
1391 public ContentHandler run() {
1392 ClassLoader cl = ClassLoader.getSystemClassLoader();
1393 ServiceLoader<ContentHandlerFactory> sl =
1394 ServiceLoader.load(ContentHandlerFactory.class, cl);
1395
1396 Iterator<ContentHandlerFactory> iterator = sl.iterator();
1397
1398 ContentHandler handler = null;
1399 while (iterator.hasNext()) {
1400 ContentHandlerFactory f;
1401 try {
1402 f = iterator.next();
1403 } catch (ServiceConfigurationError e) {
1404 if (e.getCause() instanceof SecurityException) {
1405 continue;
1406 }
1407 throw e;
1408 }
1409 handler = f.createContentHandler(contentType);
1410 if (handler != null) {
1411 break;
1412 }
1413 }
1414 return handler;
1415 }
1416 });
1417 }
1418
1419 /**
1420 * Utility function to map a MIME content type into an equivalent
1421 * pair of class name components. For example: "text/html" would
1422 * be returned as "text.html"
1423 */
1424 private String typeToPackageName(String contentType) {
1425 // make sure we canonicalize the class name: all lower case
1426 contentType = contentType.toLowerCase();
1427 int len = contentType.length();
1428 char nm[] = new char[len];
1429 contentType.getChars(0, len, nm, 0);
1430 for (int i = 0; i < len; i++) {
1431 char c = nm[i];
1432 if (c == '/') {
1433 nm[i] = '.';
1434 } else if (!('A' <= c && c <= 'Z' ||
1435 'a' <= c && c <= 'z' ||
1436 '0' <= c && c <= '9')) {
1437 nm[i] = '_';
1438 }
1439 }
1440 return new String(nm);
1441 }
1442
1443
1444 /**
1445 * Returns a vertical bar separated list of package prefixes for potential
1446 * content handlers. Tries to get the java.content.handler.pkgs property
1447 * to use as a set of package prefixes to search. Whether or not
1448 * that property has been defined, the {@value #contentClassPrefix}
1449 * is always the last one on the returned package list.
1450 */
1451 private String getContentHandlerPkgPrefixes() {
1452 String packagePrefixList =
1453 GetPropertyAction.privilegedGetProperty(contentPathProp, "");
1454
1455 if (packagePrefixList != "") {
1456 packagePrefixList += "|";
1457 }
1458
1459 return packagePrefixList + contentClassPrefix;
1460 }
1461
1462 /**
1463 * Tries to determine the content type of an object, based
1464 * on the specified "file" component of a URL.
1465 * This is a convenience method that can be used by
1466 * subclasses that override the {@code getContentType} method.
1467 *
1468 * @param fname a filename.
1469 * @return a guess as to what the content type of the object is,
1470 * based upon its file name.
1471 * @see java.net.URLConnection#getContentType()
1472 */
1473 public static String guessContentTypeFromName(String fname) {
1474 return getFileNameMap().getContentTypeFor(fname);
1475 }
1476
1477 /**
1478 * Tries to determine the type of an input stream based on the
1479 * characters at the beginning of the input stream. This method can
1480 * be used by subclasses that override the
1481 * {@code getContentType} method.
1482 * <p>
1483 * Ideally, this routine would not be needed. But many
1484 * {@code http} servers return the incorrect content type; in
1485 * addition, there are many nonstandard extensions. Direct inspection
1486 * of the bytes to determine the content type is often more accurate
1487 * than believing the content type claimed by the {@code http} server.
1488 *
1489 * @param is an input stream that supports marks.
1490 * @return a guess at the content type, or {@code null} if none
1491 * can be determined.
1492 * @exception IOException if an I/O error occurs while reading the
1493 * input stream.
1494 * @see java.io.InputStream#mark(int)
1495 * @see java.io.InputStream#markSupported()
1496 * @see java.net.URLConnection#getContentType()
1497 */
1498 public static String guessContentTypeFromStream(InputStream is)
1499 throws IOException {
1500 // If we can't read ahead safely, just give up on guessing
1501 if (!is.markSupported())
1502 return null;
1503
1504 is.mark(16);
1505 int c1 = is.read();
1506 int c2 = is.read();
1507 int c3 = is.read();
1508 int c4 = is.read();
1509 int c5 = is.read();
1510 int c6 = is.read();
1511 int c7 = is.read();
1512 int c8 = is.read();
1513 int c9 = is.read();
1514 int c10 = is.read();
1515 int c11 = is.read();
1516 int c12 = is.read();
1517 int c13 = is.read();
1518 int c14 = is.read();
1519 int c15 = is.read();
1520 int c16 = is.read();
1521 is.reset();
1522
1523 if (c1 == 0xCA && c2 == 0xFE && c3 == 0xBA && c4 == 0xBE) {
1524 return "application/java-vm";
1525 }
1526
1527 if (c1 == 0xAC && c2 == 0xED) {
1528 // next two bytes are version number, currently 0x00 0x05
1529 return "application/x-java-serialized-object";
1530 }
1531
1532 if (c1 == '<') {
1533 if (c2 == '!'
1534 || ((c2 == 'h' && (c3 == 't' && c4 == 'm' && c5 == 'l' ||
1535 c3 == 'e' && c4 == 'a' && c5 == 'd') ||
1536 (c2 == 'b' && c3 == 'o' && c4 == 'd' && c5 == 'y'))) ||
1537 ((c2 == 'H' && (c3 == 'T' && c4 == 'M' && c5 == 'L' ||
1538 c3 == 'E' && c4 == 'A' && c5 == 'D') ||
1539 (c2 == 'B' && c3 == 'O' && c4 == 'D' && c5 == 'Y')))) {
1540 return "text/html";
1541 }
1542
1543 if (c2 == '?' && c3 == 'x' && c4 == 'm' && c5 == 'l' && c6 == ' ') {
1544 return "application/xml";
1545 }
1546 }
1547
1548 // big and little (identical) endian UTF-8 encodings, with BOM
1549 if (c1 == 0xef && c2 == 0xbb && c3 == 0xbf) {
1550 if (c4 == '<' && c5 == '?' && c6 == 'x') {
1551 return "application/xml";
1552 }
1553 }
1554
1555 // big and little endian UTF-16 encodings, with byte order mark
1556 if (c1 == 0xfe && c2 == 0xff) {
1557 if (c3 == 0 && c4 == '<' && c5 == 0 && c6 == '?' &&
1558 c7 == 0 && c8 == 'x') {
1559 return "application/xml";
1560 }
1561 }
1562
1563 if (c1 == 0xff && c2 == 0xfe) {
1564 if (c3 == '<' && c4 == 0 && c5 == '?' && c6 == 0 &&
1565 c7 == 'x' && c8 == 0) {
1566 return "application/xml";
1567 }
1568 }
1569
1570 // big and little endian UTF-32 encodings, with BOM
1571 if (c1 == 0x00 && c2 == 0x00 && c3 == 0xfe && c4 == 0xff) {
1572 if (c5 == 0 && c6 == 0 && c7 == 0 && c8 == '<' &&
1573 c9 == 0 && c10 == 0 && c11 == 0 && c12 == '?' &&
1574 c13 == 0 && c14 == 0 && c15 == 0 && c16 == 'x') {
1575 return "application/xml";
1576 }
1577 }
1578
1579 if (c1 == 0xff && c2 == 0xfe && c3 == 0x00 && c4 == 0x00) {
1580 if (c5 == '<' && c6 == 0 && c7 == 0 && c8 == 0 &&
1581 c9 == '?' && c10 == 0 && c11 == 0 && c12 == 0 &&
1582 c13 == 'x' && c14 == 0 && c15 == 0 && c16 == 0) {
1583 return "application/xml";
1584 }
1585 }
1586
1587 if (c1 == 'G' && c2 == 'I' && c3 == 'F' && c4 == '8') {
1588 return "image/gif";
1589 }
1590
1591 if (c1 == '#' && c2 == 'd' && c3 == 'e' && c4 == 'f') {
1592 return "image/x-bitmap";
1593 }
1594
1595 if (c1 == '!' && c2 == ' ' && c3 == 'X' && c4 == 'P' &&
1596 c5 == 'M' && c6 == '2') {
1597 return "image/x-pixmap";
1598 }
1599
1600 if (c1 == 137 && c2 == 80 && c3 == 78 &&
1601 c4 == 71 && c5 == 13 && c6 == 10 &&
1602 c7 == 26 && c8 == 10) {
1603 return "image/png";
1604 }
1605
1606 if (c1 == 0xFF && c2 == 0xD8 && c3 == 0xFF) {
1607 if (c4 == 0xE0 || c4 == 0xEE) {
1608 return "image/jpeg";
1609 }
1610
1611 /**
1612 * File format used by digital cameras to store images.
1613 * Exif Format can be read by any application supporting
1614 * JPEG. Exif Spec can be found at:
1615 * http://www.pima.net/standards/it10/PIMA15740/Exif_2-1.PDF
1616 */
1617 if ((c4 == 0xE1) &&
1618 (c7 == 'E' && c8 == 'x' && c9 == 'i' && c10 =='f' &&
1619 c11 == 0)) {
1620 return "image/jpeg";
1621 }
1622 }
1623
1624 if ((c1 == 0x49 && c2 == 0x49 && c3 == 0x2a && c4 == 0x00)
1625 || (c1 == 0x4d && c2 == 0x4d && c3 == 0x00 && c4 == 0x2a)) {
1626 return "image/tiff";
1627 }
1628
1629 if (c1 == 0xD0 && c2 == 0xCF && c3 == 0x11 && c4 == 0xE0 &&
1630 c5 == 0xA1 && c6 == 0xB1 && c7 == 0x1A && c8 == 0xE1) {
1631
1632 /* Above is signature of Microsoft Structured Storage.
1633 * Below this, could have tests for various SS entities.
1634 * For now, just test for FlashPix.
1635 */
1636 if (checkfpx(is)) {
1637 return "image/vnd.fpx";
1638 }
1639 }
1640
1641 if (c1 == 0x2E && c2 == 0x73 && c3 == 0x6E && c4 == 0x64) {
1642 return "audio/basic"; // .au format, big endian
1643 }
1644
1645 if (c1 == 0x64 && c2 == 0x6E && c3 == 0x73 && c4 == 0x2E) {
1646 return "audio/basic"; // .au format, little endian
1647 }
1648
1649 if (c1 == 'R' && c2 == 'I' && c3 == 'F' && c4 == 'F') {
1650 /* I don't know if this is official but evidence
1651 * suggests that .wav files start with "RIFF" - brown
1652 */
1653 return "audio/x-wav";
1654 }
1655 return null;
1656 }
1657
1658 /**
1659 * Check for FlashPix image data in InputStream is. Return true if
1660 * the stream has FlashPix data, false otherwise. Before calling this
1661 * method, the stream should have already been checked to be sure it
1662 * contains Microsoft Structured Storage data.
1663 */
1664 private static boolean checkfpx(InputStream is) throws IOException {
1665
1666 /* Test for FlashPix image data in Microsoft Structured Storage format.
1667 * In general, should do this with calls to an SS implementation.
1668 * Lacking that, need to dig via offsets to get to the FlashPix
1669 * ClassID. Details:
1670 *
1671 * Offset to Fpx ClsID from beginning of stream should be:
1672 *
1673 * FpxClsidOffset = rootEntryOffset + clsidOffset
1674 *
1675 * where: clsidOffset = 0x50.
1676 * rootEntryOffset = headerSize + sectorSize*sectDirStart
1677 * + 128*rootEntryDirectory
1678 *
1679 * where: headerSize = 0x200 (always)
1680 * sectorSize = 2 raised to power of uSectorShift,
1681 * which is found in the header at
1682 * offset 0x1E.
1683 * sectDirStart = found in the header at offset 0x30.
1684 * rootEntryDirectory = in general, should search for
1685 * directory labelled as root.
1686 * We will assume value of 0 (i.e.,
1687 * rootEntry is in first directory)
1688 */
1689
1690 // Mark the stream so we can reset it. 0x100 is enough for the first
1691 // few reads, but the mark will have to be reset and set again once
1692 // the offset to the root directory entry is computed. That offset
1693 // can be very large and isn't know until the stream has been read from
1694 is.mark(0x100);
1695
1696 // Get the byte ordering located at 0x1E. 0xFE is Intel,
1697 // 0xFF is other
1698 long toSkip = (long)0x1C;
1699 long posn;
1700
1701 if ((posn = skipForward(is, toSkip)) < toSkip) {
1702 is.reset();
1703 return false;
1704 }
1705
1706 int c[] = new int[16];
1707 if (readBytes(c, 2, is) < 0) {
1708 is.reset();
1709 return false;
1710 }
1711
1712 int byteOrder = c[0];
1713
1714 posn+=2;
1715 int uSectorShift;
1716 if (readBytes(c, 2, is) < 0) {
1717 is.reset();
1718 return false;
1719 }
1720
1721 if(byteOrder == 0xFE) {
1722 uSectorShift = c[0];
1723 uSectorShift += c[1] << 8;
1724 }
1725 else {
1726 uSectorShift = c[0] << 8;
1727 uSectorShift += c[1];
1728 }
1729
1730 posn += 2;
1731 toSkip = (long)0x30 - posn;
1732 long skipped = 0;
1733 if ((skipped = skipForward(is, toSkip)) < toSkip) {
1734 is.reset();
1735 return false;
1736 }
1737 posn += skipped;
1738
1739 if (readBytes(c, 4, is) < 0) {
1740 is.reset();
1741 return false;
1742 }
1743
1744 int sectDirStart;
1745 if(byteOrder == 0xFE) {
1746 sectDirStart = c[0];
1747 sectDirStart += c[1] << 8;
1748 sectDirStart += c[2] << 16;
1749 sectDirStart += c[3] << 24;
1750 } else {
1751 sectDirStart = c[0] << 24;
1752 sectDirStart += c[1] << 16;
1753 sectDirStart += c[2] << 8;
1754 sectDirStart += c[3];
1755 }
1756 posn += 4;
1757 is.reset(); // Reset back to the beginning
1758
1759 toSkip = 0x200L + (long)(1<<uSectorShift)*sectDirStart + 0x50L;
1760
1761 // Sanity check!
1762 if (toSkip < 0) {
1763 return false;
1764 }
1765
1766 /*
1767 * How far can we skip? Is there any performance problem here?
1768 * This skip can be fairly long, at least 0x4c650 in at least
1769 * one case. Have to assume that the skip will fit in an int.
1770 * Leave room to read whole root dir
1771 */
1772 is.mark((int)toSkip+0x30);
1773
1774 if ((skipForward(is, toSkip)) < toSkip) {
1775 is.reset();
1776 return false;
1777 }
1778
1779 /* should be at beginning of ClassID, which is as follows
1780 * (in Intel byte order):
1781 * 00 67 61 56 54 C1 CE 11 85 53 00 AA 00 A1 F9 5B
1782 *
1783 * This is stored from Windows as long,short,short,char[8]
1784 * so for byte order changes, the order only changes for
1785 * the first 8 bytes in the ClassID.
1786 *
1787 * Test against this, ignoring second byte (Intel) since
1788 * this could change depending on part of Fpx file we have.
1789 */
1790
1791 if (readBytes(c, 16, is) < 0) {
1792 is.reset();
1793 return false;
1794 }
1795
1796 // intel byte order
1797 if (byteOrder == 0xFE &&
1798 c[0] == 0x00 && c[2] == 0x61 && c[3] == 0x56 &&
1799 c[4] == 0x54 && c[5] == 0xC1 && c[6] == 0xCE &&
1800 c[7] == 0x11 && c[8] == 0x85 && c[9] == 0x53 &&
1801 c[10]== 0x00 && c[11]== 0xAA && c[12]== 0x00 &&
1802 c[13]== 0xA1 && c[14]== 0xF9 && c[15]== 0x5B) {
1803 is.reset();
1804 return true;
1805 }
1806
1807 // non-intel byte order
1808 else if (c[3] == 0x00 && c[1] == 0x61 && c[0] == 0x56 &&
1809 c[5] == 0x54 && c[4] == 0xC1 && c[7] == 0xCE &&
1810 c[6] == 0x11 && c[8] == 0x85 && c[9] == 0x53 &&
1811 c[10]== 0x00 && c[11]== 0xAA && c[12]== 0x00 &&
1812 c[13]== 0xA1 && c[14]== 0xF9 && c[15]== 0x5B) {
1813 is.reset();
1814 return true;
1815 }
1816 is.reset();
1817 return false;
1818 }
1819
1820 /**
1821 * Tries to read the specified number of bytes from the stream
1822 * Returns -1, If EOF is reached before len bytes are read, returns 0
1823 * otherwise
1824 */
1825 private static int readBytes(int c[], int len, InputStream is)
1826 throws IOException {
1827
1828 byte buf[] = new byte[len];
1829 if (is.read(buf, 0, len) < len) {
1830 return -1;
1831 }
1832
1833 // fill the passed in int array
1834 for (int i = 0; i < len; i++) {
1835 c[i] = buf[i] & 0xff;
1836 }
1837 return 0;
1838 }
1839
1840
1841 /**
1842 * Skips through the specified number of bytes from the stream
1843 * until either EOF is reached, or the specified
1844 * number of bytes have been skipped
1845 */
1846 private static long skipForward(InputStream is, long toSkip)
1847 throws IOException {
1848
1849 long eachSkip = 0;
1850 long skipped = 0;
1851
1852 while (skipped != toSkip) {
1853 eachSkip = is.skip(toSkip - skipped);
1854
1855 // check if EOF is reached
1856 if (eachSkip <= 0) {
1857 if (is.read() == -1) {
1858 return skipped ;
1859 } else {
1860 skipped++;
1861 }
1862 }
1863 skipped += eachSkip;
1864 }
1865 return skipped;
1866 }
1867
1868 private void checkConnected() {
1869 if (connected)
1870 throw new IllegalStateException("Already connected");
1871 }
1872 }
1873
1874 class UnknownContentHandler extends ContentHandler {
1875 static final ContentHandler INSTANCE = new UnknownContentHandler();
1876
1877 public Object getContent(URLConnection uc) throws IOException {
1878 return uc.getInputStream();
1879 }
1880 }