1 /*
2 * Copyright (c) 1995, 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
26 package java.net;
27
28 import java.io.IOException;
29 import java.io.InputStream;
30 import java.net.spi.URLStreamHandlerProvider;
31 import java.security.AccessController;
32 import java.security.PrivilegedAction;
33 import java.util.Hashtable;
34 import java.util.Iterator;
35 import java.util.NoSuchElementException;
36 import java.util.ServiceConfigurationError;
37 import java.util.ServiceLoader;
38
39 import sun.security.util.SecurityConstants;
40
41 /**
42 * Class {@code URL} represents a Uniform Resource
43 * Locator, a pointer to a "resource" on the World
44 * Wide Web. A resource can be something as simple as a file or a
45 * directory, or it can be a reference to a more complicated object,
46 * such as a query to a database or to a search engine. More
47 * information on the types of URLs and their formats can be found at:
48 * <a href=
49 * "http://web.archive.org/web/20051219043731/http://archive.ncsa.uiuc.edu/SDG/Software/Mosaic/Demo/url-primer.html">
50 * <i>Types of URL</i></a>
51 * <p>
52 * In general, a URL can be broken into several parts. Consider the
53 * following example:
54 * <blockquote><pre>
55 * http://www.example.com/docs/resource1.html
56 * </pre></blockquote>
57 * <p>
58 * The URL above indicates that the protocol to use is
59 * {@code http} (HyperText Transfer Protocol) and that the
60 * information resides on a host machine named
61 * {@code www.example.com}. The information on that host
62 * machine is named {@code /docs/resource1.html}. The exact
63 * meaning of this name on the host machine is both protocol
64 * dependent and host dependent. The information normally resides in
65 * a file, but it could be generated on the fly. This component of
66 * the URL is called the <i>path</i> component.
67 * <p>
68 * A URL can optionally specify a "port", which is the
69 * port number to which the TCP connection is made on the remote host
70 * machine. If the port is not specified, the default port for
71 * the protocol is used instead. For example, the default port for
72 * {@code http} is {@code 80}. An alternative port could be
73 * specified as:
74 * <blockquote><pre>
75 * http://www.example.com:1080/docs/resource1.html
76 * </pre></blockquote>
77 * <p>
78 * The syntax of {@code URL} is defined by <a
79 * href="http://www.ietf.org/rfc/rfc2396.txt"><i>RFC 2396: Uniform
80 * Resource Identifiers (URI): Generic Syntax</i></a>, amended by <a
81 * href="http://www.ietf.org/rfc/rfc2732.txt"><i>RFC 2732: Format for
82 * Literal IPv6 Addresses in URLs</i></a>. The Literal IPv6 address format
83 * also supports scope_ids. The syntax and usage of scope_ids is described
84 * <a href="Inet6Address.html#scoped">here</a>.
85 * <p>
86 * A URL may have appended to it a "fragment", also known
87 * as a "ref" or a "reference". The fragment is indicated by the sharp
88 * sign character "#" followed by more characters. For example,
89 * <blockquote><pre>
90 * http://java.sun.com/index.html#chapter1
91 * </pre></blockquote>
92 * <p>
93 * This fragment is not technically part of the URL. Rather, it
94 * indicates that after the specified resource is retrieved, the
95 * application is specifically interested in that part of the
96 * document that has the tag {@code chapter1} attached to it. The
97 * meaning of a tag is resource specific.
98 * <p>
99 * An application can also specify a "relative URL",
100 * which contains only enough information to reach the resource
101 * relative to another URL. Relative URLs are frequently used within
102 * HTML pages. For example, if the contents of the URL:
103 * <blockquote><pre>
104 * http://java.sun.com/index.html
105 * </pre></blockquote>
106 * contained within it the relative URL:
107 * <blockquote><pre>
108 * FAQ.html
109 * </pre></blockquote>
110 * it would be a shorthand for:
111 * <blockquote><pre>
112 * http://java.sun.com/FAQ.html
113 * </pre></blockquote>
114 * <p>
115 * The relative URL need not specify all the components of a URL. If
116 * the protocol, host name, or port number is missing, the value is
117 * inherited from the fully specified URL. The file component must be
118 * specified. The optional fragment is not inherited.
119 * <p>
120 * The URL class does not itself encode or decode any URL components
121 * according to the escaping mechanism defined in RFC2396. It is the
122 * responsibility of the caller to encode any fields, which need to be
123 * escaped prior to calling URL, and also to decode any escaped fields,
124 * that are returned from URL. Furthermore, because URL has no knowledge
125 * of URL escaping, it does not recognise equivalence between the encoded
126 * or decoded form of the same URL. For example, the two URLs:<br>
127 * <pre> http://foo.com/hello world/ and http://foo.com/hello%20world</pre>
128 * would be considered not equal to each other.
129 * <p>
130 * Note, the {@link java.net.URI} class does perform escaping of its
131 * component fields in certain circumstances. The recommended way
132 * to manage the encoding and decoding of URLs is to use {@link java.net.URI},
133 * and to convert between these two classes using {@link #toURI()} and
134 * {@link URI#toURL()}.
135 * <p>
136 * The {@link URLEncoder} and {@link URLDecoder} classes can also be
137 * used, but only for HTML form encoding, which is not the same
138 * as the encoding scheme defined in RFC2396.
139 *
140 * @author James Gosling
141 * @since 1.0
142 */
143 public final class URL implements java.io.Serializable {
144
145 static final long serialVersionUID = -7627629688361524110L;
146
147 /**
148 * The property which specifies the package prefix list to be scanned
149 * for protocol handlers. The value of this property (if any) should
150 * be a vertical bar delimited list of package names to search through
151 * for a protocol handler to load. The policy of this class is that
152 * all protocol handlers will be in a class called <protocolname>.Handler,
153 * and each package in the list is examined in turn for a matching
154 * handler. If none are found (or the property is not specified), the
155 * default package prefix, sun.net.www.protocol, is used. The search
156 * proceeds from the first package in the list to the last and stops
157 * when a match is found.
158 */
159 private static final String protocolPathProp = "java.protocol.handler.pkgs";
160
161 /**
162 * The protocol to use (ftp, http, nntp, ... etc.) .
163 * @serial
164 */
165 private String protocol;
166
167 /**
168 * The host name to connect to.
169 * @serial
170 */
171 private String host;
172
173 /**
174 * The protocol port to connect to.
175 * @serial
176 */
177 private int port = -1;
178
179 /**
180 * The specified file name on that host. {@code file} is
181 * defined as {@code path[?query]}
182 * @serial
183 */
184 private String file;
185
186 /**
187 * The query part of this URL.
188 */
189 private transient String query;
190
191 /**
192 * The authority part of this URL.
193 * @serial
194 */
195 private String authority;
196
197 /**
198 * The path part of this URL.
199 */
200 private transient String path;
201
202 /**
203 * The userinfo part of this URL.
204 */
205 private transient String userInfo;
206
207 /**
208 * # reference.
209 * @serial
210 */
211 private String ref;
212
213 /**
214 * The host's IP address, used in equals and hashCode.
215 * Computed on demand. An uninitialized or unknown hostAddress is null.
216 */
217 transient InetAddress hostAddress;
218
219 /**
220 * The URLStreamHandler for this URL.
221 */
222 transient URLStreamHandler handler;
223
224 /* Our hash code.
225 * @serial
226 */
227 private int hashCode = -1;
228
229 /**
230 * Creates a {@code URL} object from the specified
231 * {@code protocol}, {@code host}, {@code port}
232 * number, and {@code file}.<p>
233 *
234 * {@code host} can be expressed as a host name or a literal
235 * IP address. If IPv6 literal address is used, it should be
236 * enclosed in square brackets ({@code '['} and {@code ']'}), as
237 * specified by <a
238 * href="http://www.ietf.org/rfc/rfc2732.txt">RFC 2732</a>;
239 * However, the literal IPv6 address format defined in <a
240 * href="http://www.ietf.org/rfc/rfc2373.txt"><i>RFC 2373: IP
241 * Version 6 Addressing Architecture</i></a> is also accepted.<p>
242 *
243 * Specifying a {@code port} number of {@code -1}
244 * indicates that the URL should use the default port for the
245 * protocol.<p>
246 *
247 * If this is the first URL object being created with the specified
248 * protocol, a <i>stream protocol handler</i> object, an instance of
249 * class {@code URLStreamHandler}, is created for that protocol:
250 * <ol>
251 * <li>If the application has previously set up an instance of
252 * {@code URLStreamHandlerFactory} as the stream handler factory,
253 * then the {@code createURLStreamHandler} method of that instance
254 * is called with the protocol string as an argument to create the
255 * stream protocol handler.
256 * <li>If no {@code URLStreamHandlerFactory} has yet been set up,
257 * or if the factory's {@code createURLStreamHandler} method
258 * returns {@code null}, then the {@linkplain java.util.ServiceLoader
259 * ServiceLoader} mechanism is used to locate {@linkplain
260 * java.net.spi.URLStreamHandlerProvider URLStreamHandlerProvider}
261 * implementations using the system class
262 * loader. The order that providers are located is implementation
263 * specific, and an implementation is free to cache the located
264 * providers. A {@linkplain java.util.ServiceConfigurationError
265 * ServiceConfigurationError}, {@code Error} or {@code RuntimeException}
266 * thrown from the {@code createURLStreamHandler}, if encountered, will
267 * be propagated to the calling thread. The {@code
268 * createURLStreamHandler} method of each provider, if instantiated, is
269 * invoked, with the protocol string, until a provider returns non-null,
270 * or all providers have been exhausted.
271 * <li>If the previous step fails to find a protocol handler, the
272 * constructor reads the value of the system property:
273 * <blockquote>{@code
274 * java.protocol.handler.pkgs
275 * }</blockquote>
276 * If the value of that system property is not {@code null},
277 * it is interpreted as a list of packages separated by a vertical
278 * slash character '{@code |}'. The constructor tries to load
279 * the class named:
280 * <blockquote>{@code
281 * <package>.<protocol>.Handler
282 * }</blockquote>
283 * where {@code <package>} is replaced by the name of the package
284 * and {@code <protocol>} is replaced by the name of the protocol.
285 * If this class does not exist, or if the class exists but it is not
286 * a subclass of {@code URLStreamHandler}, then the next package
287 * in the list is tried.
288 * <li>If the previous step fails to find a protocol handler, then the
289 * constructor tries to load a built-in protocol handler.
290 * If this class does not exist, or if the class exists but it is not a
291 * subclass of {@code URLStreamHandler}, then a
292 * {@code MalformedURLException} is thrown.
293 * </ol>
294 *
295 * <p>Protocol handlers for the following protocols are guaranteed
296 * to exist on the search path :-
297 * <blockquote><pre>
298 * http, https, file, and jar
299 * </pre></blockquote>
300 * Protocol handlers for additional protocols may also be available.
301 * Some protocol handlers, for example those used for loading platform
302 * classes or classes on the class path, may not be overridden. The details
303 * of such restrictions, and when those restrictions apply (during
304 * initialization of the runtime for example), are implementation specific
305 * and therefore not specified
306 *
307 * <p>No validation of the inputs is performed by this constructor.
308 *
309 * @param protocol the name of the protocol to use.
310 * @param host the name of the host.
311 * @param port the port number on the host.
312 * @param file the file on the host
313 * @exception MalformedURLException if an unknown protocol is specified.
314 * @see java.lang.System#getProperty(java.lang.String)
315 * @see java.net.URL#setURLStreamHandlerFactory(
316 * java.net.URLStreamHandlerFactory)
317 * @see java.net.URLStreamHandler
318 * @see java.net.URLStreamHandlerFactory#createURLStreamHandler(
319 * java.lang.String)
320 */
321 public URL(String protocol, String host, int port, String file)
322 throws MalformedURLException
323 {
324 this(protocol, host, port, file, null);
325 }
326
327 /**
328 * Creates a URL from the specified {@code protocol}
329 * name, {@code host} name, and {@code file} name. The
330 * default port for the specified protocol is used.
331 * <p>
332 * This method is equivalent to calling the four-argument
333 * constructor with the arguments being {@code protocol},
334 * {@code host}, {@code -1}, and {@code file}.
335 *
336 * No validation of the inputs is performed by this constructor.
337 *
338 * @param protocol the name of the protocol to use.
339 * @param host the name of the host.
340 * @param file the file on the host.
341 * @exception MalformedURLException if an unknown protocol is specified.
342 * @see java.net.URL#URL(java.lang.String, java.lang.String,
343 * int, java.lang.String)
344 */
345 public URL(String protocol, String host, String file)
346 throws MalformedURLException {
347 this(protocol, host, -1, file);
348 }
349
350 /**
351 * Creates a {@code URL} object from the specified
352 * {@code protocol}, {@code host}, {@code port}
353 * number, {@code file}, and {@code handler}. Specifying
354 * a {@code port} number of {@code -1} indicates that
355 * the URL should use the default port for the protocol. Specifying
356 * a {@code handler} of {@code null} indicates that the URL
357 * should use a default stream handler for the protocol, as outlined
358 * for:
359 * java.net.URL#URL(java.lang.String, java.lang.String, int,
360 * java.lang.String)
361 *
362 * <p>If the handler is not null and there is a security manager,
363 * the security manager's {@code checkPermission}
364 * method is called with a
365 * {@code NetPermission("specifyStreamHandler")} permission.
366 * This may result in a SecurityException.
367 *
368 * No validation of the inputs is performed by this constructor.
369 *
370 * @param protocol the name of the protocol to use.
371 * @param host the name of the host.
372 * @param port the port number on the host.
373 * @param file the file on the host
374 * @param handler the stream handler for the URL.
375 * @exception MalformedURLException if an unknown protocol is specified.
376 * @exception SecurityException
377 * if a security manager exists and its
378 * {@code checkPermission} method doesn't allow
379 * specifying a stream handler explicitly.
380 * @see java.lang.System#getProperty(java.lang.String)
381 * @see java.net.URL#setURLStreamHandlerFactory(
382 * java.net.URLStreamHandlerFactory)
383 * @see java.net.URLStreamHandler
384 * @see java.net.URLStreamHandlerFactory#createURLStreamHandler(
385 * java.lang.String)
386 * @see SecurityManager#checkPermission
387 * @see java.net.NetPermission
388 */
389 public URL(String protocol, String host, int port, String file,
390 URLStreamHandler handler) throws MalformedURLException {
391 if (handler != null) {
392 SecurityManager sm = System.getSecurityManager();
393 if (sm != null) {
394 // check for permission to specify a handler
395 checkSpecifyHandler(sm);
396 }
397 }
398
399 protocol = protocol.toLowerCase();
400 this.protocol = protocol;
401 if (host != null) {
402
403 /**
404 * if host is a literal IPv6 address,
405 * we will make it conform to RFC 2732
406 */
407 if (host.indexOf(':') >= 0 && !host.startsWith("[")) {
408 host = "["+host+"]";
409 }
410 this.host = host;
411
412 if (port < -1) {
413 throw new MalformedURLException("Invalid port number :" +
414 port);
415 }
416 this.port = port;
417 authority = (port == -1) ? host : host + ":" + port;
418 }
419
420 Parts parts = new Parts(file);
421 path = parts.getPath();
422 query = parts.getQuery();
423
424 if (query != null) {
425 this.file = path + "?" + query;
426 } else {
427 this.file = path;
428 }
429 ref = parts.getRef();
430
431 // Note: we don't do validation of the URL here. Too risky to change
432 // right now, but worth considering for future reference. -br
433 if (handler == null &&
434 (handler = getURLStreamHandler(protocol)) == null) {
435 throw new MalformedURLException("unknown protocol: " + protocol);
436 }
437 this.handler = handler;
438 }
439
440 /**
441 * Creates a {@code URL} object from the {@code String}
442 * representation.
443 * <p>
444 * This constructor is equivalent to a call to the two-argument
445 * constructor with a {@code null} first argument.
446 *
447 * @param spec the {@code String} to parse as a URL.
448 * @exception MalformedURLException if no protocol is specified, or an
449 * unknown protocol is found, or {@code spec} is {@code null}.
450 * @see java.net.URL#URL(java.net.URL, java.lang.String)
451 */
452 public URL(String spec) throws MalformedURLException {
453 this(null, spec);
454 }
455
456 /**
457 * Creates a URL by parsing the given spec within a specified context.
458 *
459 * The new URL is created from the given context URL and the spec
460 * argument as described in
461 * RFC2396 "Uniform Resource Identifiers : Generic * Syntax" :
462 * <blockquote><pre>
463 * <scheme>://<authority><path>?<query>#<fragment>
464 * </pre></blockquote>
465 * The reference is parsed into the scheme, authority, path, query and
466 * fragment parts. If the path component is empty and the scheme,
467 * authority, and query components are undefined, then the new URL is a
468 * reference to the current document. Otherwise, the fragment and query
469 * parts present in the spec are used in the new URL.
470 * <p>
471 * If the scheme component is defined in the given spec and does not match
472 * the scheme of the context, then the new URL is created as an absolute
473 * URL based on the spec alone. Otherwise the scheme component is inherited
474 * from the context URL.
475 * <p>
476 * If the authority component is present in the spec then the spec is
477 * treated as absolute and the spec authority and path will replace the
478 * context authority and path. If the authority component is absent in the
479 * spec then the authority of the new URL will be inherited from the
480 * context.
481 * <p>
482 * If the spec's path component begins with a slash character
483 * "/" then the
484 * path is treated as absolute and the spec path replaces the context path.
485 * <p>
486 * Otherwise, the path is treated as a relative path and is appended to the
487 * context path, as described in RFC2396. Also, in this case,
488 * the path is canonicalized through the removal of directory
489 * changes made by occurrences of ".." and ".".
490 * <p>
491 * For a more detailed description of URL parsing, refer to RFC2396.
492 *
493 * @param context the context in which to parse the specification.
494 * @param spec the {@code String} to parse as a URL.
495 * @exception MalformedURLException if no protocol is specified, or an
496 * unknown protocol is found, or {@code spec} is {@code null}.
497 * @see java.net.URL#URL(java.lang.String, java.lang.String,
498 * int, java.lang.String)
499 * @see java.net.URLStreamHandler
500 * @see java.net.URLStreamHandler#parseURL(java.net.URL,
501 * java.lang.String, int, int)
502 */
503 public URL(URL context, String spec) throws MalformedURLException {
504 this(context, spec, null);
505 }
506
507 /**
508 * Creates a URL by parsing the given spec with the specified handler
509 * within a specified context. If the handler is null, the parsing
510 * occurs as with the two argument constructor.
511 *
512 * @param context the context in which to parse the specification.
513 * @param spec the {@code String} to parse as a URL.
514 * @param handler the stream handler for the URL.
515 * @exception MalformedURLException if no protocol is specified, or an
516 * unknown protocol is found, or {@code spec} is {@code null}.
517 * @exception SecurityException
518 * if a security manager exists and its
519 * {@code checkPermission} method doesn't allow
520 * specifying a stream handler.
521 * @see java.net.URL#URL(java.lang.String, java.lang.String,
522 * int, java.lang.String)
523 * @see java.net.URLStreamHandler
524 * @see java.net.URLStreamHandler#parseURL(java.net.URL,
525 * java.lang.String, int, int)
526 */
527 public URL(URL context, String spec, URLStreamHandler handler)
528 throws MalformedURLException
529 {
530 String original = spec;
531 int i, limit, c;
532 int start = 0;
533 String newProtocol = null;
534 boolean aRef=false;
535 boolean isRelative = false;
536
537 // Check for permission to specify a handler
538 if (handler != null) {
539 SecurityManager sm = System.getSecurityManager();
540 if (sm != null) {
541 checkSpecifyHandler(sm);
542 }
543 }
544
545 try {
546 limit = spec.length();
547 while ((limit > 0) && (spec.charAt(limit - 1) <= ' ')) {
548 limit--; //eliminate trailing whitespace
549 }
550 while ((start < limit) && (spec.charAt(start) <= ' ')) {
551 start++; // eliminate leading whitespace
552 }
553
554 if (spec.regionMatches(true, start, "url:", 0, 4)) {
555 start += 4;
556 }
557 if (start < spec.length() && spec.charAt(start) == '#') {
558 /* we're assuming this is a ref relative to the context URL.
559 * This means protocols cannot start w/ '#', but we must parse
560 * ref URL's like: "hello:there" w/ a ':' in them.
561 */
562 aRef=true;
563 }
564 for (i = start ; !aRef && (i < limit) &&
565 ((c = spec.charAt(i)) != '/') ; i++) {
566 if (c == ':') {
567
568 String s = spec.substring(start, i).toLowerCase();
569 if (isValidProtocol(s)) {
570 newProtocol = s;
571 start = i + 1;
572 }
573 break;
574 }
575 }
576
577 // Only use our context if the protocols match.
578 protocol = newProtocol;
579 if ((context != null) && ((newProtocol == null) ||
580 newProtocol.equalsIgnoreCase(context.protocol))) {
581 // inherit the protocol handler from the context
582 // if not specified to the constructor
583 if (handler == null) {
584 handler = context.handler;
585 }
586
587 // If the context is a hierarchical URL scheme and the spec
588 // contains a matching scheme then maintain backwards
589 // compatibility and treat it as if the spec didn't contain
590 // the scheme; see 5.2.3 of RFC2396
591 if (context.path != null && context.path.startsWith("/"))
592 newProtocol = null;
593
594 if (newProtocol == null) {
595 protocol = context.protocol;
596 authority = context.authority;
597 userInfo = context.userInfo;
598 host = context.host;
599 port = context.port;
600 file = context.file;
601 path = context.path;
602 isRelative = true;
603 }
604 }
605
606 if (protocol == null) {
607 throw new MalformedURLException("no protocol: "+original);
608 }
609
610 // Get the protocol handler if not specified or the protocol
611 // of the context could not be used
612 if (handler == null &&
613 (handler = getURLStreamHandler(protocol)) == null) {
614 throw new MalformedURLException("unknown protocol: "+protocol);
615 }
616
617 this.handler = handler;
618
619 i = spec.indexOf('#', start);
620 if (i >= 0) {
621 ref = spec.substring(i + 1, limit);
622 limit = i;
623 }
624
625 /*
626 * Handle special case inheritance of query and fragment
627 * implied by RFC2396 section 5.2.2.
628 */
629 if (isRelative && start == limit) {
630 query = context.query;
631 if (ref == null) {
632 ref = context.ref;
633 }
634 }
635
636 handler.parseURL(this, spec, start, limit);
637
638 } catch(MalformedURLException e) {
639 throw e;
640 } catch(Exception e) {
641 MalformedURLException exception = new MalformedURLException(e.getMessage());
642 exception.initCause(e);
643 throw exception;
644 }
645 }
646
647 /*
648 * Returns true if specified string is a valid protocol name.
649 */
650 private boolean isValidProtocol(String protocol) {
651 int len = protocol.length();
652 if (len < 1)
653 return false;
654 char c = protocol.charAt(0);
655 if (!Character.isLetter(c))
656 return false;
657 for (int i = 1; i < len; i++) {
658 c = protocol.charAt(i);
659 if (!Character.isLetterOrDigit(c) && c != '.' && c != '+' &&
660 c != '-') {
661 return false;
662 }
663 }
664 return true;
665 }
666
667 /*
668 * Checks for permission to specify a stream handler.
669 */
670 private void checkSpecifyHandler(SecurityManager sm) {
671 sm.checkPermission(SecurityConstants.SPECIFY_HANDLER_PERMISSION);
672 }
673
674 /**
675 * Sets the fields of the URL. This is not a public method so that
676 * only URLStreamHandlers can modify URL fields. URLs are
677 * otherwise constant.
678 *
679 * @param protocol the name of the protocol to use
680 * @param host the name of the host
681 @param port the port number on the host
682 * @param file the file on the host
683 * @param ref the internal reference in the URL
684 */
685 void set(String protocol, String host, int port,
686 String file, String ref) {
687 synchronized (this) {
688 this.protocol = protocol;
689 this.host = host;
690 authority = port == -1 ? host : host + ":" + port;
691 this.port = port;
692 this.file = file;
693 this.ref = ref;
694 /* This is very important. We must recompute this after the
695 * URL has been changed. */
696 hashCode = -1;
697 hostAddress = null;
698 int q = file.lastIndexOf('?');
699 if (q != -1) {
700 query = file.substring(q+1);
701 path = file.substring(0, q);
702 } else
703 path = file;
704 }
705 }
706
707 /**
708 * Sets the specified 8 fields of the URL. This is not a public method so
709 * that only URLStreamHandlers can modify URL fields. URLs are otherwise
710 * constant.
711 *
712 * @param protocol the name of the protocol to use
713 * @param host the name of the host
714 * @param port the port number on the host
715 * @param authority the authority part for the url
716 * @param userInfo the username and password
717 * @param path the file on the host
718 * @param ref the internal reference in the URL
719 * @param query the query part of this URL
720 * @since 1.3
721 */
722 void set(String protocol, String host, int port,
723 String authority, String userInfo, String path,
724 String query, String ref) {
725 synchronized (this) {
726 this.protocol = protocol;
727 this.host = host;
728 this.port = port;
729 this.file = query == null ? path : path + "?" + query;
730 this.userInfo = userInfo;
731 this.path = path;
732 this.ref = ref;
733 /* This is very important. We must recompute this after the
734 * URL has been changed. */
735 hashCode = -1;
736 hostAddress = null;
737 this.query = query;
738 this.authority = authority;
739 }
740 }
741
742 /**
743 * Gets the query part of this {@code URL}.
744 *
745 * @return the query part of this {@code URL},
746 * or <CODE>null</CODE> if one does not exist
747 * @since 1.3
748 */
749 public String getQuery() {
750 return query;
751 }
752
753 /**
754 * Gets the path part of this {@code URL}.
755 *
756 * @return the path part of this {@code URL}, or an
757 * empty string if one does not exist
758 * @since 1.3
759 */
760 public String getPath() {
761 return path;
762 }
763
764 /**
765 * Gets the userInfo part of this {@code URL}.
766 *
767 * @return the userInfo part of this {@code URL}, or
768 * <CODE>null</CODE> if one does not exist
769 * @since 1.3
770 */
771 public String getUserInfo() {
772 return userInfo;
773 }
774
775 /**
776 * Gets the authority part of this {@code URL}.
777 *
778 * @return the authority part of this {@code URL}
779 * @since 1.3
780 */
781 public String getAuthority() {
782 return authority;
783 }
784
785 /**
786 * Gets the port number of this {@code URL}.
787 *
788 * @return the port number, or -1 if the port is not set
789 */
790 public int getPort() {
791 return port;
792 }
793
794 /**
795 * Gets the default port number of the protocol associated
796 * with this {@code URL}. If the URL scheme or the URLStreamHandler
797 * for the URL do not define a default port number,
798 * then -1 is returned.
799 *
800 * @return the port number
801 * @since 1.4
802 */
803 public int getDefaultPort() {
804 return handler.getDefaultPort();
805 }
806
807 /**
808 * Gets the protocol name of this {@code URL}.
809 *
810 * @return the protocol of this {@code URL}.
811 */
812 public String getProtocol() {
813 return protocol;
814 }
815
816 /**
817 * Gets the host name of this {@code URL}, if applicable.
818 * The format of the host conforms to RFC 2732, i.e. for a
819 * literal IPv6 address, this method will return the IPv6 address
820 * enclosed in square brackets ({@code '['} and {@code ']'}).
821 *
822 * @return the host name of this {@code URL}.
823 */
824 public String getHost() {
825 return host;
826 }
827
828 /**
829 * Gets the file name of this {@code URL}.
830 * The returned file portion will be
831 * the same as <CODE>getPath()</CODE>, plus the concatenation of
832 * the value of <CODE>getQuery()</CODE>, if any. If there is
833 * no query portion, this method and <CODE>getPath()</CODE> will
834 * return identical results.
835 *
836 * @return the file name of this {@code URL},
837 * or an empty string if one does not exist
838 */
839 public String getFile() {
840 return file;
841 }
842
843 /**
844 * Gets the anchor (also known as the "reference") of this
845 * {@code URL}.
846 *
847 * @return the anchor (also known as the "reference") of this
848 * {@code URL}, or <CODE>null</CODE> if one does not exist
849 */
850 public String getRef() {
851 return ref;
852 }
853
854 /**
855 * Compares this URL for equality with another object.<p>
856 *
857 * If the given object is not a URL then this method immediately returns
858 * {@code false}.<p>
859 *
860 * Two URL objects are equal if they have the same protocol, reference
861 * equivalent hosts, have the same port number on the host, and the same
862 * file and fragment of the file.<p>
863 *
864 * Two hosts are considered equivalent if both host names can be resolved
865 * into the same IP addresses; else if either host name can't be
866 * resolved, the host names must be equal without regard to case; or both
867 * host names equal to null.<p>
868 *
869 * Since hosts comparison requires name resolution, this operation is a
870 * blocking operation. <p>
871 *
872 * Note: The defined behavior for {@code equals} is known to
873 * be inconsistent with virtual hosting in HTTP.
874 *
875 * @param obj the URL to compare against.
876 * @return {@code true} if the objects are the same;
877 * {@code false} otherwise.
878 */
879 public boolean equals(Object obj) {
880 if (!(obj instanceof URL))
881 return false;
882 URL u2 = (URL)obj;
883
884 return handler.equals(this, u2);
885 }
886
887 /**
888 * Creates an integer suitable for hash table indexing.<p>
889 *
890 * The hash code is based upon all the URL components relevant for URL
891 * comparison. As such, this operation is a blocking operation.
892 *
893 * @return a hash code for this {@code URL}.
894 */
895 public synchronized int hashCode() {
896 if (hashCode != -1)
897 return hashCode;
898
899 hashCode = handler.hashCode(this);
900 return hashCode;
901 }
902
903 /**
904 * Compares two URLs, excluding the fragment component.<p>
905 *
906 * Returns {@code true} if this {@code URL} and the
907 * {@code other} argument are equal without taking the
908 * fragment component into consideration.
909 *
910 * @param other the {@code URL} to compare against.
911 * @return {@code true} if they reference the same remote object;
912 * {@code false} otherwise.
913 */
914 public boolean sameFile(URL other) {
915 return handler.sameFile(this, other);
916 }
917
918 /**
919 * Constructs a string representation of this {@code URL}. The
920 * string is created by calling the {@code toExternalForm}
921 * method of the stream protocol handler for this object.
922 *
923 * @return a string representation of this object.
924 * @see java.net.URL#URL(java.lang.String, java.lang.String, int,
925 * java.lang.String)
926 * @see java.net.URLStreamHandler#toExternalForm(java.net.URL)
927 */
928 public String toString() {
929 return toExternalForm();
930 }
931
932 /**
933 * Constructs a string representation of this {@code URL}. The
934 * string is created by calling the {@code toExternalForm}
935 * method of the stream protocol handler for this object.
936 *
937 * @return a string representation of this object.
938 * @see java.net.URL#URL(java.lang.String, java.lang.String,
939 * int, java.lang.String)
940 * @see java.net.URLStreamHandler#toExternalForm(java.net.URL)
941 */
942 public String toExternalForm() {
943 return handler.toExternalForm(this);
944 }
945
946 /**
947 * Returns a {@link java.net.URI} equivalent to this URL.
948 * This method functions in the same way as {@code new URI (this.toString())}.
949 * <p>Note, any URL instance that complies with RFC 2396 can be converted
950 * to a URI. However, some URLs that are not strictly in compliance
951 * can not be converted to a URI.
952 *
953 * @exception URISyntaxException if this URL is not formatted strictly according to
954 * to RFC2396 and cannot be converted to a URI.
955 *
956 * @return a URI instance equivalent to this URL.
957 * @since 1.5
958 */
959 public URI toURI() throws URISyntaxException {
960 return new URI (toString());
961 }
962
963 /**
964 * Returns a {@link java.net.URLConnection URLConnection} instance that
965 * represents a connection to the remote object referred to by the
966 * {@code URL}.
967 *
968 * <P>A new instance of {@linkplain java.net.URLConnection URLConnection} is
969 * created every time when invoking the
970 * {@linkplain java.net.URLStreamHandler#openConnection(URL)
971 * URLStreamHandler.openConnection(URL)} method of the protocol handler for
972 * this URL.</P>
973 *
974 * <P>It should be noted that a URLConnection instance does not establish
975 * the actual network connection on creation. This will happen only when
976 * calling {@linkplain java.net.URLConnection#connect() URLConnection.connect()}.</P>
977 *
978 * <P>If for the URL's protocol (such as HTTP or JAR), there
979 * exists a public, specialized URLConnection subclass belonging
980 * to one of the following packages or one of their subpackages:
981 * java.lang, java.io, java.util, java.net, the connection
982 * returned will be of that subclass. For example, for HTTP an
983 * HttpURLConnection will be returned, and for JAR a
984 * JarURLConnection will be returned.</P>
985 *
986 * @return a {@link java.net.URLConnection URLConnection} linking
987 * to the URL.
988 * @exception IOException if an I/O exception occurs.
989 * @see java.net.URL#URL(java.lang.String, java.lang.String,
990 * int, java.lang.String)
991 */
992 public URLConnection openConnection() throws java.io.IOException {
993 return handler.openConnection(this);
994 }
995
996 /**
997 * Same as {@link #openConnection()}, except that the connection will be
998 * made through the specified proxy; Protocol handlers that do not
999 * support proxing will ignore the proxy parameter and make a
1000 * normal connection.
1001 *
1002 * Invoking this method preempts the system's default
1003 * {@link java.net.ProxySelector ProxySelector} settings.
1004 *
1005 * @param proxy the Proxy through which this connection
1006 * will be made. If direct connection is desired,
1007 * Proxy.NO_PROXY should be specified.
1008 * @return a {@code URLConnection} to the URL.
1009 * @exception IOException if an I/O exception occurs.
1010 * @exception SecurityException if a security manager is present
1011 * and the caller doesn't have permission to connect
1012 * to the proxy.
1013 * @exception IllegalArgumentException will be thrown if proxy is null,
1014 * or proxy has the wrong type
1015 * @exception UnsupportedOperationException if the subclass that
1016 * implements the protocol handler doesn't support
1017 * this method.
1018 * @see java.net.URL#URL(java.lang.String, java.lang.String,
1019 * int, java.lang.String)
1020 * @see java.net.URLConnection
1021 * @see java.net.URLStreamHandler#openConnection(java.net.URL,
1022 * java.net.Proxy)
1023 * @since 1.5
1024 */
1025 public URLConnection openConnection(Proxy proxy)
1026 throws java.io.IOException {
1027 if (proxy == null) {
1028 throw new IllegalArgumentException("proxy can not be null");
1029 }
1030
1031 // Create a copy of Proxy as a security measure
1032 Proxy p = proxy == Proxy.NO_PROXY ? Proxy.NO_PROXY : sun.net.ApplicationProxy.create(proxy);
1033 SecurityManager sm = System.getSecurityManager();
1034 if (p.type() != Proxy.Type.DIRECT && sm != null) {
1035 InetSocketAddress epoint = (InetSocketAddress) p.address();
1036 if (epoint.isUnresolved())
1037 sm.checkConnect(epoint.getHostName(), epoint.getPort());
1038 else
1039 sm.checkConnect(epoint.getAddress().getHostAddress(),
1040 epoint.getPort());
1041 }
1042 return handler.openConnection(this, p);
1043 }
1044
1045 /**
1046 * Opens a connection to this {@code URL} and returns an
1047 * {@code InputStream} for reading from that connection. This
1048 * method is a shorthand for:
1049 * <blockquote><pre>
1050 * openConnection().getInputStream()
1051 * </pre></blockquote>
1052 *
1053 * @return an input stream for reading from the URL connection.
1054 * @exception IOException if an I/O exception occurs.
1055 * @see java.net.URL#openConnection()
1056 * @see java.net.URLConnection#getInputStream()
1057 */
1058 public final InputStream openStream() throws java.io.IOException {
1059 return openConnection().getInputStream();
1060 }
1061
1062 /**
1063 * Gets the contents of this URL. This method is a shorthand for:
1064 * <blockquote><pre>
1065 * openConnection().getContent()
1066 * </pre></blockquote>
1067 *
1068 * @return the contents of this URL.
1069 * @exception IOException if an I/O exception occurs.
1070 * @see java.net.URLConnection#getContent()
1071 */
1072 public final Object getContent() throws java.io.IOException {
1073 return openConnection().getContent();
1074 }
1075
1076 /**
1077 * Gets the contents of this URL. This method is a shorthand for:
1078 * <blockquote><pre>
1079 * openConnection().getContent(classes)
1080 * </pre></blockquote>
1081 *
1082 * @param classes an array of Java types
1083 * @return the content object of this URL that is the first match of
1084 * the types specified in the classes array.
1085 * null if none of the requested types are supported.
1086 * @exception IOException if an I/O exception occurs.
1087 * @see java.net.URLConnection#getContent(Class[])
1088 * @since 1.3
1089 */
1090 public final Object getContent(Class<?>[] classes)
1091 throws java.io.IOException {
1092 return openConnection().getContent(classes);
1093 }
1094
1095 /**
1096 * The URLStreamHandler factory.
1097 */
1098 private static volatile URLStreamHandlerFactory factory;
1099
1100 /**
1101 * Sets an application's {@code URLStreamHandlerFactory}.
1102 * This method can be called at most once in a given Java Virtual
1103 * Machine.
1104 *
1105 *<p> The {@code URLStreamHandlerFactory} instance is used to
1106 *construct a stream protocol handler from a protocol name.
1107 *
1108 * <p> If there is a security manager, this method first calls
1109 * the security manager's {@code checkSetFactory} method
1110 * to ensure the operation is allowed.
1111 * This could result in a SecurityException.
1112 *
1113 * @param fac the desired factory.
1114 * @exception Error if the application has already set a factory.
1115 * @exception SecurityException if a security manager exists and its
1116 * {@code checkSetFactory} method doesn't allow
1117 * the operation.
1118 * @see java.net.URL#URL(java.lang.String, java.lang.String,
1119 * int, java.lang.String)
1120 * @see java.net.URLStreamHandlerFactory
1121 * @see SecurityManager#checkSetFactory
1122 */
1123 public static void setURLStreamHandlerFactory(URLStreamHandlerFactory fac) {
1124 synchronized (streamHandlerLock) {
1125 if (factory != null) {
1126 throw new Error("factory already defined");
1127 }
1128 SecurityManager security = System.getSecurityManager();
1129 if (security != null) {
1130 security.checkSetFactory();
1131 }
1132 handlers.clear();
1133
1134 // safe publication of URLStreamHandlerFactory with volatile write
1135 factory = fac;
1136 }
1137 }
1138
1139 private static final URLStreamHandlerFactory defaultFactory = new DefaultFactory();
1140
1141 private static class DefaultFactory implements URLStreamHandlerFactory {
1142 private static String PREFIX = "sun.net.www.protocol";
1143
1144 public URLStreamHandler createURLStreamHandler(String protocol) {
1145 String name = PREFIX + "." + protocol + ".Handler";
1146 try {
1147 Class<?> c = Class.forName(name);
1148 return (URLStreamHandler)c.newInstance();
1149 } catch (ClassNotFoundException x) {
1150 // ignore
1151 } catch (Exception e) {
1152 // For compatibility, all Exceptions are ignored.
1153 // any number of exceptions can get thrown here
1154 }
1155 return null;
1156 }
1157 }
1158
1159 private static URLStreamHandler lookupViaProperty(String protocol) {
1160 String packagePrefixList = java.security.AccessController.doPrivileged(
1161 new PrivilegedAction<>() {
1162 public String run() {
1163 return System.getProperty(protocolPathProp, "");
1164 }
1165 });
1166 String[] packagePrefixes = packagePrefixList.split("\\|");
1167
1168 URLStreamHandler handler = null;
1169 for (int i=0; handler == null && i<packagePrefixes.length; i++) {
1170 String packagePrefix = packagePrefixes[i].trim();
1171 try {
1172 String clsName = packagePrefix + "." + protocol + ".Handler";
1173 Class<?> cls = null;
1174 try {
1175 cls = Class.forName(clsName);
1176 } catch (ClassNotFoundException e) {
1177 ClassLoader cl = ClassLoader.getSystemClassLoader();
1178 if (cl != null) {
1179 cls = cl.loadClass(clsName);
1180 }
1181 }
1182 if (cls != null) {
1183 handler = (URLStreamHandler)cls.newInstance();
1184 }
1185 } catch (Exception e) {
1186 // any number of exceptions can get thrown here
1187 }
1188 }
1189 return handler;
1190 }
1191
1192 private static Iterator<URLStreamHandlerProvider> providers() {
1193 return new Iterator<>() {
1194
1195 ClassLoader cl = ClassLoader.getSystemClassLoader();
1196 ServiceLoader<URLStreamHandlerProvider> sl =
1197 ServiceLoader.load(URLStreamHandlerProvider.class, cl);
1198 Iterator<URLStreamHandlerProvider> i = sl.iterator();
1199
1200 URLStreamHandlerProvider next = null;
1201
1202 private boolean getNext() {
1203 while (next == null) {
1204 try {
1205 if (!i.hasNext())
1206 return false;
1207 next = i.next();
1208 } catch (ServiceConfigurationError sce) {
1209 if (sce.getCause() instanceof SecurityException) {
1210 // Ignore security exceptions
1211 continue;
1212 }
1213 throw sce;
1214 }
1215 }
1216 return true;
1217 }
1218
1219 public boolean hasNext() {
1220 return getNext();
1221 }
1222
1223 public URLStreamHandlerProvider next() {
1224 if (!getNext())
1225 throw new NoSuchElementException();
1226 URLStreamHandlerProvider n = next;
1227 next = null;
1228 return n;
1229 }
1230 };
1231 }
1232
1233 // Thread-local gate to prevent recursive provider lookups
1234 private static ThreadLocal<Object> gate = new ThreadLocal<>();
1235
1236 private static URLStreamHandler lookupViaProviders(final String protocol) {
1237 if (!sun.misc.VM.isBooted())
1238 return null;
1239
1240 if (gate.get() != null)
1241 throw new Error("Circular loading of URL stream handler providers detected");
1242
1243 gate.set(gate);
1244 try {
1245 return AccessController.doPrivileged(
1246 new PrivilegedAction<>() {
1247 public URLStreamHandler run() {
1248 Iterator<URLStreamHandlerProvider> itr = providers();
1249 while (itr.hasNext()) {
1250 URLStreamHandlerProvider f = itr.next();
1251 URLStreamHandler h = f.createURLStreamHandler(protocol);
1252 if (h != null)
1253 return h;
1254 }
1255 return null;
1256 }
1257 });
1258 } finally {
1259 gate.set(null);
1260 }
1261 }
1262
1263 private static final String[] NON_OVERRIDEABLE_PROTOCOLS = {"file", "jrt"};
1264 private static boolean isOverrideable(String protocol) {
1265 for (String p : NON_OVERRIDEABLE_PROTOCOLS)
1266 if (protocol.equalsIgnoreCase(p))
1267 return false;
1268 return true;
1269 }
1270
1271 /**
1272 * A table of protocol handlers.
1273 */
1274 static Hashtable<String,URLStreamHandler> handlers = new Hashtable<>();
1275 private static final Object streamHandlerLock = new Object();
1276
1277 /**
1278 * Returns the Stream Handler.
1279 * @param protocol the protocol to use
1280 */
1281 static URLStreamHandler getURLStreamHandler(String protocol) {
1282
1283 URLStreamHandler handler = handlers.get(protocol);
1284
1285 if (handler != null) {
1286 return handler;
1287 }
1288
1289 URLStreamHandlerFactory fac;
1290 boolean checkedWithFactory = false;
1291
1292 if (isOverrideable(protocol)) {
1293 // Use the factory (if any). Volatile read makes
1294 // URLStreamHandlerFactory appear fully initialized to current thread.
1295 fac = factory;
1296 if (fac != null) {
1297 handler = fac.createURLStreamHandler(protocol);
1298 checkedWithFactory = true;
1299 }
1300
1301 if (handler == null && !protocol.equalsIgnoreCase("jar")) {
1302 handler = lookupViaProviders(protocol);
1303 }
1304
1305 if (handler == null) {
1306 handler = lookupViaProperty(protocol);
1307 }
1308 }
1309
1310 synchronized (streamHandlerLock) {
1311 if (handler == null) {
1312 // Try the built-in protocol handler
1313 handler = defaultFactory.createURLStreamHandler(protocol);
1314 } else {
1315 URLStreamHandler handler2 = null;
1316
1317 // Check again with hashtable just in case another
1318 // thread created a handler since we last checked
1319 handler2 = handlers.get(protocol);
1320
1321 if (handler2 != null) {
1322 return handler2;
1323 }
1324
1325 // Check with factory if another thread set a
1326 // factory since our last check
1327 if (!checkedWithFactory && (fac = factory) != null) {
1328 handler2 = fac.createURLStreamHandler(protocol);
1329 }
1330
1331 if (handler2 != null) {
1332 // The handler from the factory must be given more
1333 // importance. Discard the default handler that
1334 // this thread created.
1335 handler = handler2;
1336 }
1337 }
1338
1339 // Insert this handler into the hashtable
1340 if (handler != null) {
1341 handlers.put(protocol, handler);
1342 }
1343 }
1344
1345 return handler;
1346 }
1347
1348 /**
1349 * WriteObject is called to save the state of the URL to an
1350 * ObjectOutputStream. The handler is not saved since it is
1351 * specific to this system.
1352 *
1353 * @serialData the default write object value. When read back in,
1354 * the reader must ensure that calling getURLStreamHandler with
1355 * the protocol variable returns a valid URLStreamHandler and
1356 * throw an IOException if it does not.
1357 */
1358 private synchronized void writeObject(java.io.ObjectOutputStream s)
1359 throws IOException
1360 {
1361 s.defaultWriteObject(); // write the fields
1362 }
1363
1364 /**
1365 * readObject is called to restore the state of the URL from the
1366 * stream. It reads the components of the URL and finds the local
1367 * stream handler.
1368 */
1369 private synchronized void readObject(java.io.ObjectInputStream s)
1370 throws IOException, ClassNotFoundException
1371 {
1372 s.defaultReadObject(); // read the fields
1373 if ((handler = getURLStreamHandler(protocol)) == null) {
1374 throw new IOException("unknown protocol: " + protocol);
1375 }
1376
1377 // Construct authority part
1378 if (authority == null &&
1379 ((host != null && host.length() > 0) || port != -1)) {
1380 if (host == null)
1381 host = "";
1382 authority = (port == -1) ? host : host + ":" + port;
1383
1384 // Handle hosts with userInfo in them
1385 int at = host.lastIndexOf('@');
1386 if (at != -1) {
1387 userInfo = host.substring(0, at);
1388 host = host.substring(at+1);
1389 }
1390 } else if (authority != null) {
1391 // Construct user info part
1392 int ind = authority.indexOf('@');
1393 if (ind != -1)
1394 userInfo = authority.substring(0, ind);
1395 }
1396
1397 // Construct path and query part
1398 path = null;
1399 query = null;
1400 if (file != null) {
1401 // Fix: only do this if hierarchical?
1402 int q = file.lastIndexOf('?');
1403 if (q != -1) {
1404 query = file.substring(q+1);
1405 path = file.substring(0, q);
1406 } else
1407 path = file;
1408 }
1409 }
1410 }
1411
1412 class Parts {
1413 String path, query, ref;
1414
1415 Parts(String file) {
1416 int ind = file.indexOf('#');
1417 ref = ind < 0 ? null: file.substring(ind + 1);
1418 file = ind < 0 ? file: file.substring(0, ind);
1419 int q = file.lastIndexOf('?');
1420 if (q != -1) {
1421 query = file.substring(q+1);
1422 path = file.substring(0, q);
1423 } else {
1424 path = file;
1425 }
1426 }
1427
1428 String getPath() {
1429 return path;
1430 }
1431
1432 String getQuery() {
1433 return query;
1434 }
1435
1436 String getRef() {
1437 return ref;
1438 }
1439 }