1 /* 2 * Copyright (c) 2000, 2010, 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.InvalidObjectException; 30 import java.io.ObjectInputStream; 31 import java.io.ObjectOutputStream; 32 import java.io.Serializable; 33 import java.nio.ByteBuffer; 34 import java.nio.CharBuffer; 35 import java.nio.charset.CharsetDecoder; 36 import java.nio.charset.CharsetEncoder; 37 import java.nio.charset.CoderResult; 38 import java.nio.charset.CodingErrorAction; 39 import java.nio.charset.CharacterCodingException; 40 import java.text.Normalizer; 41 import sun.nio.cs.ThreadLocalCoders; 42 43 import java.lang.Character; // for javadoc 44 import java.lang.NullPointerException; // for javadoc 45 46 47 /** 48 * Represents a Uniform Resource Identifier (URI) reference. 49 * 50 * <p> Aside from some minor deviations noted below, an instance of this 51 * class represents a URI reference as defined by 52 * <a href="http://www.ietf.org/rfc/rfc2396.txt"><i>RFC 2396: Uniform 53 * Resource Identifiers (URI): Generic Syntax</i></a>, amended by <a 54 * href="http://www.ietf.org/rfc/rfc2732.txt"><i>RFC 2732: Format for 55 * Literal IPv6 Addresses in URLs</i></a>. The Literal IPv6 address format 56 * also supports scope_ids. The syntax and usage of scope_ids is described 57 * <a href="Inet6Address.html#scoped">here</a>. 58 * This class provides constructors for creating URI instances from 59 * their components or by parsing their string forms, methods for accessing the 60 * various components of an instance, and methods for normalizing, resolving, 61 * and relativizing URI instances. Instances of this class are immutable. 62 * 63 * 64 * <h4> URI syntax and components </h4> 65 * 66 * At the highest level a URI reference (hereinafter simply "URI") in string 67 * form has the syntax 68 * 69 * <blockquote> 70 * [<i>scheme</i><tt><b>:</b></tt><i></i>]<i>scheme-specific-part</i>[<tt><b>#</b></tt><i>fragment</i>] 71 * </blockquote> 72 * 73 * where square brackets [...] delineate optional components and the characters 74 * <tt><b>:</b></tt> and <tt><b>#</b></tt> stand for themselves. 75 * 76 * <p> An <i>absolute</i> URI specifies a scheme; a URI that is not absolute is 77 * said to be <i>relative</i>. URIs are also classified according to whether 78 * they are <i>opaque</i> or <i>hierarchical</i>. 79 * 80 * <p> An <i>opaque</i> URI is an absolute URI whose scheme-specific part does 81 * not begin with a slash character (<tt>'/'</tt>). Opaque URIs are not 82 * subject to further parsing. Some examples of opaque URIs are: 83 * 84 * <blockquote><table cellpadding=0 cellspacing=0 summary="layout"> 85 * <tr><td><tt>mailto:java-net@java.sun.com</tt><td></tr> 86 * <tr><td><tt>news:comp.lang.java</tt><td></tr> 87 * <tr><td><tt>urn:isbn:096139210x</tt></td></tr> 88 * </table></blockquote> 89 * 90 * <p> A <i>hierarchical</i> URI is either an absolute URI whose 91 * scheme-specific part begins with a slash character, or a relative URI, that 92 * is, a URI that does not specify a scheme. Some examples of hierarchical 93 * URIs are: 94 * 95 * <blockquote> 96 * <tt>http://java.sun.com/j2se/1.3/</tt><br> 97 * <tt>docs/guide/collections/designfaq.html#28</tt><br> 98 * <tt>../../../demo/jfc/SwingSet2/src/SwingSet2.java</tt><br> 99 * <tt>file:///~/calendar</tt> 100 * </blockquote> 101 * 102 * <p> A hierarchical URI is subject to further parsing according to the syntax 103 * 104 * <blockquote> 105 * [<i>scheme</i><tt><b>:</b></tt>][<tt><b>//</b></tt><i>authority</i>][<i>path</i>][<tt><b>?</b></tt><i>query</i>][<tt><b>#</b></tt><i>fragment</i>] 106 * </blockquote> 107 * 108 * where the characters <tt><b>:</b></tt>, <tt><b>/</b></tt>, 109 * <tt><b>?</b></tt>, and <tt><b>#</b></tt> stand for themselves. The 110 * scheme-specific part of a hierarchical URI consists of the characters 111 * between the scheme and fragment components. 112 * 113 * <p> The authority component of a hierarchical URI is, if specified, either 114 * <i>server-based</i> or <i>registry-based</i>. A server-based authority 115 * parses according to the familiar syntax 116 * 117 * <blockquote> 118 * [<i>user-info</i><tt><b>@</b></tt>]<i>host</i>[<tt><b>:</b></tt><i>port</i>] 119 * </blockquote> 120 * 121 * where the characters <tt><b>@</b></tt> and <tt><b>:</b></tt> stand for 122 * themselves. Nearly all URI schemes currently in use are server-based. An 123 * authority component that does not parse in this way is considered to be 124 * registry-based. 125 * 126 * <p> The path component of a hierarchical URI is itself said to be absolute 127 * if it begins with a slash character (<tt>'/'</tt>); otherwise it is 128 * relative. The path of a hierarchical URI that is either absolute or 129 * specifies an authority is always absolute. 130 * 131 * <p> All told, then, a URI instance has the following nine components: 132 * 133 * <blockquote><table summary="Describes the components of a URI:scheme,scheme-specific-part,authority,user-info,host,port,path,query,fragment"> 134 * <tr><th><i>Component</i></th><th><i>Type</i></th></tr> 135 * <tr><td>scheme</td><td><tt>String</tt></td></tr> 136 * <tr><td>scheme-specific-part </td><td><tt>String</tt></td></tr> 137 * <tr><td>authority</td><td><tt>String</tt></td></tr> 138 * <tr><td>user-info</td><td><tt>String</tt></td></tr> 139 * <tr><td>host</td><td><tt>String</tt></td></tr> 140 * <tr><td>port</td><td><tt>int</tt></td></tr> 141 * <tr><td>path</td><td><tt>String</tt></td></tr> 142 * <tr><td>query</td><td><tt>String</tt></td></tr> 143 * <tr><td>fragment</td><td><tt>String</tt></td></tr> 144 * </table></blockquote> 145 * 146 * In a given instance any particular component is either <i>undefined</i> or 147 * <i>defined</i> with a distinct value. Undefined string components are 148 * represented by <tt>null</tt>, while undefined integer components are 149 * represented by <tt>-1</tt>. A string component may be defined to have the 150 * empty string as its value; this is not equivalent to that component being 151 * undefined. 152 * 153 * <p> Whether a particular component is or is not defined in an instance 154 * depends upon the type of the URI being represented. An absolute URI has a 155 * scheme component. An opaque URI has a scheme, a scheme-specific part, and 156 * possibly a fragment, but has no other components. A hierarchical URI always 157 * has a path (though it may be empty) and a scheme-specific-part (which at 158 * least contains the path), and may have any of the other components. If the 159 * authority component is present and is server-based then the host component 160 * will be defined and the user-information and port components may be defined. 161 * 162 * 163 * <h4> Operations on URI instances </h4> 164 * 165 * The key operations supported by this class are those of 166 * <i>normalization</i>, <i>resolution</i>, and <i>relativization</i>. 167 * 168 * <p> <i>Normalization</i> is the process of removing unnecessary <tt>"."</tt> 169 * and <tt>".."</tt> segments from the path component of a hierarchical URI. 170 * Each <tt>"."</tt> segment is simply removed. A <tt>".."</tt> segment is 171 * removed only if it is preceded by a non-<tt>".."</tt> segment. 172 * Normalization has no effect upon opaque URIs. 173 * 174 * <p> <i>Resolution</i> is the process of resolving one URI against another, 175 * <i>base</i> URI. The resulting URI is constructed from components of both 176 * URIs in the manner specified by RFC 2396, taking components from the 177 * base URI for those not specified in the original. For hierarchical URIs, 178 * the path of the original is resolved against the path of the base and then 179 * normalized. The result, for example, of resolving 180 * 181 * <blockquote> 182 * <tt>docs/guide/collections/designfaq.html#28 </tt>(1) 183 * </blockquote> 184 * 185 * against the base URI <tt>http://java.sun.com/j2se/1.3/</tt> is the result 186 * URI 187 * 188 * <blockquote> 189 * <tt>http://java.sun.com/j2se/1.3/docs/guide/collections/designfaq.html#28</tt> 190 * </blockquote> 191 * 192 * Resolving the relative URI 193 * 194 * <blockquote> 195 * <tt>../../../demo/jfc/SwingSet2/src/SwingSet2.java </tt>(2) 196 * </blockquote> 197 * 198 * against this result yields, in turn, 199 * 200 * <blockquote> 201 * <tt>http://java.sun.com/j2se/1.3/demo/jfc/SwingSet2/src/SwingSet2.java</tt> 202 * </blockquote> 203 * 204 * Resolution of both absolute and relative URIs, and of both absolute and 205 * relative paths in the case of hierarchical URIs, is supported. Resolving 206 * the URI <tt>file:///~calendar</tt> against any other URI simply yields the 207 * original URI, since it is absolute. Resolving the relative URI (2) above 208 * against the relative base URI (1) yields the normalized, but still relative, 209 * URI 210 * 211 * <blockquote> 212 * <tt>demo/jfc/SwingSet2/src/SwingSet2.java</tt> 213 * </blockquote> 214 * 215 * <p> <i>Relativization</i>, finally, is the inverse of resolution: For any 216 * two normalized URIs <i>u</i> and <i>v</i>, 217 * 218 * <blockquote> 219 * <i>u</i><tt>.relativize(</tt><i>u</i><tt>.resolve(</tt><i>v</i><tt>)).equals(</tt><i>v</i><tt>)</tt> and<br> 220 * <i>u</i><tt>.resolve(</tt><i>u</i><tt>.relativize(</tt><i>v</i><tt>)).equals(</tt><i>v</i><tt>)</tt> .<br> 221 * </blockquote> 222 * 223 * This operation is often useful when constructing a document containing URIs 224 * that must be made relative to the base URI of the document wherever 225 * possible. For example, relativizing the URI 226 * 227 * <blockquote> 228 * <tt>http://java.sun.com/j2se/1.3/docs/guide/index.html</tt> 229 * </blockquote> 230 * 231 * against the base URI 232 * 233 * <blockquote> 234 * <tt>http://java.sun.com/j2se/1.3</tt> 235 * </blockquote> 236 * 237 * yields the relative URI <tt>docs/guide/index.html</tt>. 238 * 239 * 240 * <h4> Character categories </h4> 241 * 242 * RFC 2396 specifies precisely which characters are permitted in the 243 * various components of a URI reference. The following categories, most of 244 * which are taken from that specification, are used below to describe these 245 * constraints: 246 * 247 * <blockquote><table cellspacing=2 summary="Describes categories alpha,digit,alphanum,unreserved,punct,reserved,escaped,and other"> 248 * <tr><th valign=top><i>alpha</i></th> 249 * <td>The US-ASCII alphabetic characters, 250 * <tt>'A'</tt> through <tt>'Z'</tt> 251 * and <tt>'a'</tt> through <tt>'z'</tt></td></tr> 252 * <tr><th valign=top><i>digit</i></th> 253 * <td>The US-ASCII decimal digit characters, 254 * <tt>'0'</tt> through <tt>'9'</tt></td></tr> 255 * <tr><th valign=top><i>alphanum</i></th> 256 * <td>All <i>alpha</i> and <i>digit</i> characters</td></tr> 257 * <tr><th valign=top><i>unreserved</i> </th> 258 * <td>All <i>alphanum</i> characters together with those in the string 259 * <tt>"_-!.~'()*"</tt></td></tr> 260 * <tr><th valign=top><i>punct</i></th> 261 * <td>The characters in the string <tt>",;:$&+="</tt></td></tr> 262 * <tr><th valign=top><i>reserved</i></th> 263 * <td>All <i>punct</i> characters together with those in the string 264 * <tt>"?/[]@"</tt></td></tr> 265 * <tr><th valign=top><i>escaped</i></th> 266 * <td>Escaped octets, that is, triplets consisting of the percent 267 * character (<tt>'%'</tt>) followed by two hexadecimal digits 268 * (<tt>'0'</tt>-<tt>'9'</tt>, <tt>'A'</tt>-<tt>'F'</tt>, and 269 * <tt>'a'</tt>-<tt>'f'</tt>)</td></tr> 270 * <tr><th valign=top><i>other</i></th> 271 * <td>The Unicode characters that are not in the US-ASCII character set, 272 * are not control characters (according to the {@link 273 * java.lang.Character#isISOControl(char) Character.isISOControl} 274 * method), and are not space characters (according to the {@link 275 * java.lang.Character#isSpaceChar(char) Character.isSpaceChar} 276 * method) <i>(<b>Deviation from RFC 2396</b>, which is 277 * limited to US-ASCII)</i></td></tr> 278 * </table></blockquote> 279 * 280 * <p><a name="legal-chars"></a> The set of all legal URI characters consists of 281 * the <i>unreserved</i>, <i>reserved</i>, <i>escaped</i>, and <i>other</i> 282 * characters. 283 * 284 * 285 * <h4> Escaped octets, quotation, encoding, and decoding </h4> 286 * 287 * RFC 2396 allows escaped octets to appear in the user-info, path, query, and 288 * fragment components. Escaping serves two purposes in URIs: 289 * 290 * <ul> 291 * 292 * <li><p> To <i>encode</i> non-US-ASCII characters when a URI is required to 293 * conform strictly to RFC 2396 by not containing any <i>other</i> 294 * characters. </p></li> 295 * 296 * <li><p> To <i>quote</i> characters that are otherwise illegal in a 297 * component. The user-info, path, query, and fragment components differ 298 * slightly in terms of which characters are considered legal and illegal. 299 * </p></li> 300 * 301 * </ul> 302 * 303 * These purposes are served in this class by three related operations: 304 * 305 * <ul> 306 * 307 * <li><p><a name="encode"></a> A character is <i>encoded</i> by replacing it 308 * with the sequence of escaped octets that represent that character in the 309 * UTF-8 character set. The Euro currency symbol (<tt>'\u20AC'</tt>), 310 * for example, is encoded as <tt>"%E2%82%AC"</tt>. <i>(<b>Deviation from 311 * RFC 2396</b>, which does not specify any particular character 312 * set.)</i> </p></li> 313 * 314 * <li><p><a name="quote"></a> An illegal character is <i>quoted</i> simply by 315 * encoding it. The space character, for example, is quoted by replacing it 316 * with <tt>"%20"</tt>. UTF-8 contains US-ASCII, hence for US-ASCII 317 * characters this transformation has exactly the effect required by 318 * RFC 2396. </p></li> 319 * 320 * <li><p><a name="decode"></a> 321 * A sequence of escaped octets is <i>decoded</i> by 322 * replacing it with the sequence of characters that it represents in the 323 * UTF-8 character set. UTF-8 contains US-ASCII, hence decoding has the 324 * effect of de-quoting any quoted US-ASCII characters as well as that of 325 * decoding any encoded non-US-ASCII characters. If a <a 326 * href="../nio/charset/CharsetDecoder.html#ce">decoding error</a> occurs 327 * when decoding the escaped octets then the erroneous octets are replaced by 328 * <tt>'\uFFFD'</tt>, the Unicode replacement character. </p></li> 329 * 330 * </ul> 331 * 332 * These operations are exposed in the constructors and methods of this class 333 * as follows: 334 * 335 * <ul> 336 * 337 * <li><p> The {@link #URI(java.lang.String) <code>single-argument 338 * constructor</code>} requires any illegal characters in its argument to be 339 * quoted and preserves any escaped octets and <i>other</i> characters that 340 * are present. </p></li> 341 * 342 * <li><p> The {@link 343 * #URI(java.lang.String,java.lang.String,java.lang.String,int,java.lang.String,java.lang.String,java.lang.String) 344 * <code>multi-argument constructors</code>} quote illegal characters as 345 * required by the components in which they appear. The percent character 346 * (<tt>'%'</tt>) is always quoted by these constructors. Any <i>other</i> 347 * characters are preserved. </p></li> 348 * 349 * <li><p> The {@link #getRawUserInfo() getRawUserInfo}, {@link #getRawPath() 350 * getRawPath}, {@link #getRawQuery() getRawQuery}, {@link #getRawFragment() 351 * getRawFragment}, {@link #getRawAuthority() getRawAuthority}, and {@link 352 * #getRawSchemeSpecificPart() getRawSchemeSpecificPart} methods return the 353 * values of their corresponding components in raw form, without interpreting 354 * any escaped octets. The strings returned by these methods may contain 355 * both escaped octets and <i>other</i> characters, and will not contain any 356 * illegal characters. </p></li> 357 * 358 * <li><p> The {@link #getUserInfo() getUserInfo}, {@link #getPath() 359 * getPath}, {@link #getQuery() getQuery}, {@link #getFragment() 360 * getFragment}, {@link #getAuthority() getAuthority}, and {@link 361 * #getSchemeSpecificPart() getSchemeSpecificPart} methods decode any escaped 362 * octets in their corresponding components. The strings returned by these 363 * methods may contain both <i>other</i> characters and illegal characters, 364 * and will not contain any escaped octets. </p></li> 365 * 366 * <li><p> The {@link #toString() toString} method returns a URI string with 367 * all necessary quotation but which may contain <i>other</i> characters. 368 * </p></li> 369 * 370 * <li><p> The {@link #toASCIIString() toASCIIString} method returns a fully 371 * quoted and encoded URI string that does not contain any <i>other</i> 372 * characters. </p></li> 373 * 374 * </ul> 375 * 376 * 377 * <h4> Identities </h4> 378 * 379 * For any URI <i>u</i>, it is always the case that 380 * 381 * <blockquote> 382 * <tt>new URI(</tt><i>u</i><tt>.toString()).equals(</tt><i>u</i><tt>)</tt> . 383 * </blockquote> 384 * 385 * For any URI <i>u</i> that does not contain redundant syntax such as two 386 * slashes before an empty authority (as in <tt>file:///tmp/</tt> ) or a 387 * colon following a host name but no port (as in 388 * <tt>http://java.sun.com:</tt> ), and that does not encode characters 389 * except those that must be quoted, the following identities also hold: 390 * 391 * <blockquote> 392 * <tt>new URI(</tt><i>u</i><tt>.getScheme(),<br> 393 * </tt><i>u</i><tt>.getSchemeSpecificPart(),<br> 394 * </tt><i>u</i><tt>.getFragment())<br> 395 * .equals(</tt><i>u</i><tt>)</tt> 396 * </blockquote> 397 * 398 * in all cases, 399 * 400 * <blockquote> 401 * <tt>new URI(</tt><i>u</i><tt>.getScheme(),<br> 402 * </tt><i>u</i><tt>.getUserInfo(), </tt><i>u</i><tt>.getAuthority(),<br> 403 * </tt><i>u</i><tt>.getPath(), </tt><i>u</i><tt>.getQuery(),<br> 404 * </tt><i>u</i><tt>.getFragment())<br> 405 * .equals(</tt><i>u</i><tt>)</tt> 406 * </blockquote> 407 * 408 * if <i>u</i> is hierarchical, and 409 * 410 * <blockquote> 411 * <tt>new URI(</tt><i>u</i><tt>.getScheme(),<br> 412 * </tt><i>u</i><tt>.getUserInfo(), </tt><i>u</i><tt>.getHost(), </tt><i>u</i><tt>.getPort(),<br> 413 * </tt><i>u</i><tt>.getPath(), </tt><i>u</i><tt>.getQuery(),<br> 414 * </tt><i>u</i><tt>.getFragment())<br> 415 * .equals(</tt><i>u</i><tt>)</tt> 416 * </blockquote> 417 * 418 * if <i>u</i> is hierarchical and has either no authority or a server-based 419 * authority. 420 * 421 * 422 * <h4> URIs, URLs, and URNs </h4> 423 * 424 * A URI is a uniform resource <i>identifier</i> while a URL is a uniform 425 * resource <i>locator</i>. Hence every URL is a URI, abstractly speaking, but 426 * not every URI is a URL. This is because there is another subcategory of 427 * URIs, uniform resource <i>names</i> (URNs), which name resources but do not 428 * specify how to locate them. The <tt>mailto</tt>, <tt>news</tt>, and 429 * <tt>isbn</tt> URIs shown above are examples of URNs. 430 * 431 * <p> The conceptual distinction between URIs and URLs is reflected in the 432 * differences between this class and the {@link URL} class. 433 * 434 * <p> An instance of this class represents a URI reference in the syntactic 435 * sense defined by RFC 2396. A URI may be either absolute or relative. 436 * A URI string is parsed according to the generic syntax without regard to the 437 * scheme, if any, that it specifies. No lookup of the host, if any, is 438 * performed, and no scheme-dependent stream handler is constructed. Equality, 439 * hashing, and comparison are defined strictly in terms of the character 440 * content of the instance. In other words, a URI instance is little more than 441 * a structured string that supports the syntactic, scheme-independent 442 * operations of comparison, normalization, resolution, and relativization. 443 * 444 * <p> An instance of the {@link URL} class, by contrast, represents the 445 * syntactic components of a URL together with some of the information required 446 * to access the resource that it describes. A URL must be absolute, that is, 447 * it must always specify a scheme. A URL string is parsed according to its 448 * scheme. A stream handler is always established for a URL, and in fact it is 449 * impossible to create a URL instance for a scheme for which no handler is 450 * available. Equality and hashing depend upon both the scheme and the 451 * Internet address of the host, if any; comparison is not defined. In other 452 * words, a URL is a structured string that supports the syntactic operation of 453 * resolution as well as the network I/O operations of looking up the host and 454 * opening a connection to the specified resource. 455 * 456 * 457 * @author Mark Reinhold 458 * @since 1.4 459 * 460 * @see <a href="http://www.ietf.org/rfc/rfc2279.txt"><i>RFC 2279: UTF-8, a 461 * transformation format of ISO 10646</i></a>, <br><a 462 * href="http://www.ietf.org/rfc/rfc2373.txt"><i>RFC 2373: IPv6 Addressing 463 * Architecture</i></a>, <br><a 464 * href="http://www.ietf.org/rfc/rfc2396.txt"><i>RFC 2396: Uniform 465 * Resource Identifiers (URI): Generic Syntax</i></a>, <br><a 466 * href="http://www.ietf.org/rfc/rfc2732.txt"><i>RFC 2732: Format for 467 * Literal IPv6 Addresses in URLs</i></a>, <br><a 468 * href="URISyntaxException.html">URISyntaxException</a> 469 */ 470 471 public final class URI 472 implements Comparable<URI>, Serializable 473 { 474 475 // Note: Comments containing the word "ASSERT" indicate places where a 476 // throw of an InternalError should be replaced by an appropriate assertion 477 // statement once asserts are enabled in the build. 478 479 static final long serialVersionUID = -6052424284110960213L; 480 481 482 // -- Properties and components of this instance -- 483 484 // Components of all URIs: [<scheme>:]<scheme-specific-part>[#<fragment>] 485 private transient String scheme; // null ==> relative URI 486 private transient String fragment; 487 488 // Hierarchical URI components: [//<authority>]<path>[?<query>] 489 private transient String authority; // Registry or server 490 491 // Server-based authority: [<userInfo>@]<host>[:<port>] 492 private transient String userInfo; 493 private transient String host; // null ==> registry-based 494 private transient int port = -1; // -1 ==> undefined 495 496 // Remaining components of hierarchical URIs 497 private transient String path; // null ==> opaque 498 private transient String query; 499 500 // The remaining fields may be computed on demand 501 502 private volatile transient String schemeSpecificPart; 503 private volatile transient int hash; // Zero ==> undefined 504 505 private volatile transient String decodedUserInfo = null; 506 private volatile transient String decodedAuthority = null; 507 private volatile transient String decodedPath = null; 508 private volatile transient String decodedQuery = null; 509 private volatile transient String decodedFragment = null; 510 private volatile transient String decodedSchemeSpecificPart = null; 511 512 /** 513 * The string form of this URI. 514 * 515 * @serial 516 */ 517 private volatile String string; // The only serializable field 518 519 520 521 // -- Constructors and factories -- 522 523 private URI() { } // Used internally 524 525 /** 526 * Constructs a URI by parsing the given string. 527 * 528 * <p> This constructor parses the given string exactly as specified by the 529 * grammar in <a 530 * href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>, 531 * Appendix A, <b><i>except for the following deviations:</i></b> </p> 532 * 533 * <ul type=disc> 534 * 535 * <li><p> An empty authority component is permitted as long as it is 536 * followed by a non-empty path, a query component, or a fragment 537 * component. This allows the parsing of URIs such as 538 * <tt>"file:///foo/bar"</tt>, which seems to be the intent of 539 * RFC 2396 although the grammar does not permit it. If the 540 * authority component is empty then the user-information, host, and port 541 * components are undefined. </p></li> 542 * 543 * <li><p> Empty relative paths are permitted; this seems to be the 544 * intent of RFC 2396 although the grammar does not permit it. The 545 * primary consequence of this deviation is that a standalone fragment 546 * such as <tt>"#foo"</tt> parses as a relative URI with an empty path 547 * and the given fragment, and can be usefully <a 548 * href="#resolve-frag">resolved</a> against a base URI. 549 * 550 * <li><p> IPv4 addresses in host components are parsed rigorously, as 551 * specified by <a 552 * href="http://www.ietf.org/rfc/rfc2732.txt">RFC 2732</a>: Each 553 * element of a dotted-quad address must contain no more than three 554 * decimal digits. Each element is further constrained to have a value 555 * no greater than 255. </p></li> 556 * 557 * <li> <p> Hostnames in host components that comprise only a single 558 * domain label are permitted to start with an <i>alphanum</i> 559 * character. This seems to be the intent of <a 560 * href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a> 561 * section 3.2.2 although the grammar does not permit it. The 562 * consequence of this deviation is that the authority component of a 563 * hierarchical URI such as <tt>s://123</tt>, will parse as a server-based 564 * authority. </p></li> 565 * 566 * <li><p> IPv6 addresses are permitted for the host component. An IPv6 567 * address must be enclosed in square brackets (<tt>'['</tt> and 568 * <tt>']'</tt>) as specified by <a 569 * href="http://www.ietf.org/rfc/rfc2732.txt">RFC 2732</a>. The 570 * IPv6 address itself must parse according to <a 571 * href="http://www.ietf.org/rfc/rfc2373.txt">RFC 2373</a>. IPv6 572 * addresses are further constrained to describe no more than sixteen 573 * bytes of address information, a constraint implicit in RFC 2373 574 * but not expressible in the grammar. </p></li> 575 * 576 * <li><p> Characters in the <i>other</i> category are permitted wherever 577 * RFC 2396 permits <i>escaped</i> octets, that is, in the 578 * user-information, path, query, and fragment components, as well as in 579 * the authority component if the authority is registry-based. This 580 * allows URIs to contain Unicode characters beyond those in the US-ASCII 581 * character set. </p></li> 582 * 583 * </ul> 584 * 585 * @param str The string to be parsed into a URI 586 * 587 * @throws NullPointerException 588 * If <tt>str</tt> is <tt>null</tt> 589 * 590 * @throws URISyntaxException 591 * If the given string violates RFC 2396, as augmented 592 * by the above deviations 593 */ 594 public URI(String str) throws URISyntaxException { 595 new Parser(str).parse(false); 596 } 597 598 /** 599 * Constructs a hierarchical URI from the given components. 600 * 601 * <p> If a scheme is given then the path, if also given, must either be 602 * empty or begin with a slash character (<tt>'/'</tt>). Otherwise a 603 * component of the new URI may be left undefined by passing <tt>null</tt> 604 * for the corresponding parameter or, in the case of the <tt>port</tt> 605 * parameter, by passing <tt>-1</tt>. 606 * 607 * <p> This constructor first builds a URI string from the given components 608 * according to the rules specified in <a 609 * href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>, 610 * section 5.2, step 7: </p> 611 * 612 * <ol> 613 * 614 * <li><p> Initially, the result string is empty. </p></li> 615 * 616 * <li><p> If a scheme is given then it is appended to the result, 617 * followed by a colon character (<tt>':'</tt>). </p></li> 618 * 619 * <li><p> If user information, a host, or a port are given then the 620 * string <tt>"//"</tt> is appended. </p></li> 621 * 622 * <li><p> If user information is given then it is appended, followed by 623 * a commercial-at character (<tt>'@'</tt>). Any character not in the 624 * <i>unreserved</i>, <i>punct</i>, <i>escaped</i>, or <i>other</i> 625 * categories is <a href="#quote">quoted</a>. </p></li> 626 * 627 * <li><p> If a host is given then it is appended. If the host is a 628 * literal IPv6 address but is not enclosed in square brackets 629 * (<tt>'['</tt> and <tt>']'</tt>) then the square brackets are added. 630 * </p></li> 631 * 632 * <li><p> If a port number is given then a colon character 633 * (<tt>':'</tt>) is appended, followed by the port number in decimal. 634 * </p></li> 635 * 636 * <li><p> If a path is given then it is appended. Any character not in 637 * the <i>unreserved</i>, <i>punct</i>, <i>escaped</i>, or <i>other</i> 638 * categories, and not equal to the slash character (<tt>'/'</tt>) or the 639 * commercial-at character (<tt>'@'</tt>), is quoted. </p></li> 640 * 641 * <li><p> If a query is given then a question-mark character 642 * (<tt>'?'</tt>) is appended, followed by the query. Any character that 643 * is not a <a href="#legal-chars">legal URI character</a> is quoted. 644 * </p></li> 645 * 646 * <li><p> Finally, if a fragment is given then a hash character 647 * (<tt>'#'</tt>) is appended, followed by the fragment. Any character 648 * that is not a legal URI character is quoted. </p></li> 649 * 650 * </ol> 651 * 652 * <p> The resulting URI string is then parsed as if by invoking the {@link 653 * #URI(String)} constructor and then invoking the {@link 654 * #parseServerAuthority()} method upon the result; this may cause a {@link 655 * URISyntaxException} to be thrown. </p> 656 * 657 * @param scheme Scheme name 658 * @param userInfo User name and authorization information 659 * @param host Host name 660 * @param port Port number 661 * @param path Path 662 * @param query Query 663 * @param fragment Fragment 664 * 665 * @throws URISyntaxException 666 * If both a scheme and a path are given but the path is relative, 667 * if the URI string constructed from the given components violates 668 * RFC 2396, or if the authority component of the string is 669 * present but cannot be parsed as a server-based authority 670 */ 671 public URI(String scheme, 672 String userInfo, String host, int port, 673 String path, String query, String fragment) 674 throws URISyntaxException 675 { 676 String s = toString(scheme, null, 677 null, userInfo, host, port, 678 path, query, fragment); 679 checkPath(s, scheme, path); 680 new Parser(s).parse(true); 681 } 682 683 /** 684 * Constructs a hierarchical URI from the given components. 685 * 686 * <p> If a scheme is given then the path, if also given, must either be 687 * empty or begin with a slash character (<tt>'/'</tt>). Otherwise a 688 * component of the new URI may be left undefined by passing <tt>null</tt> 689 * for the corresponding parameter. 690 * 691 * <p> This constructor first builds a URI string from the given components 692 * according to the rules specified in <a 693 * href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>, 694 * section 5.2, step 7: </p> 695 * 696 * <ol> 697 * 698 * <li><p> Initially, the result string is empty. </p></li> 699 * 700 * <li><p> If a scheme is given then it is appended to the result, 701 * followed by a colon character (<tt>':'</tt>). </p></li> 702 * 703 * <li><p> If an authority is given then the string <tt>"//"</tt> is 704 * appended, followed by the authority. If the authority contains a 705 * literal IPv6 address then the address must be enclosed in square 706 * brackets (<tt>'['</tt> and <tt>']'</tt>). Any character not in the 707 * <i>unreserved</i>, <i>punct</i>, <i>escaped</i>, or <i>other</i> 708 * categories, and not equal to the commercial-at character 709 * (<tt>'@'</tt>), is <a href="#quote">quoted</a>. </p></li> 710 * 711 * <li><p> If a path is given then it is appended. Any character not in 712 * the <i>unreserved</i>, <i>punct</i>, <i>escaped</i>, or <i>other</i> 713 * categories, and not equal to the slash character (<tt>'/'</tt>) or the 714 * commercial-at character (<tt>'@'</tt>), is quoted. </p></li> 715 * 716 * <li><p> If a query is given then a question-mark character 717 * (<tt>'?'</tt>) is appended, followed by the query. Any character that 718 * is not a <a href="#legal-chars">legal URI character</a> is quoted. 719 * </p></li> 720 * 721 * <li><p> Finally, if a fragment is given then a hash character 722 * (<tt>'#'</tt>) is appended, followed by the fragment. Any character 723 * that is not a legal URI character is quoted. </p></li> 724 * 725 * </ol> 726 * 727 * <p> The resulting URI string is then parsed as if by invoking the {@link 728 * #URI(String)} constructor and then invoking the {@link 729 * #parseServerAuthority()} method upon the result; this may cause a {@link 730 * URISyntaxException} to be thrown. </p> 731 * 732 * @param scheme Scheme name 733 * @param authority Authority 734 * @param path Path 735 * @param query Query 736 * @param fragment Fragment 737 * 738 * @throws URISyntaxException 739 * If both a scheme and a path are given but the path is relative, 740 * if the URI string constructed from the given components violates 741 * RFC 2396, or if the authority component of the string is 742 * present but cannot be parsed as a server-based authority 743 */ 744 public URI(String scheme, 745 String authority, 746 String path, String query, String fragment) 747 throws URISyntaxException 748 { 749 String s = toString(scheme, null, 750 authority, null, null, -1, 751 path, query, fragment); 752 checkPath(s, scheme, path); 753 new Parser(s).parse(false); 754 } 755 756 /** 757 * Constructs a hierarchical URI from the given components. 758 * 759 * <p> A component may be left undefined by passing <tt>null</tt>. 760 * 761 * <p> This convenience constructor works as if by invoking the 762 * seven-argument constructor as follows: 763 * 764 * <blockquote><tt> 765 * new {@link #URI(String, String, String, int, String, String, String) 766 * URI}(scheme, null, host, -1, path, null, fragment); 767 * </tt></blockquote> 768 * 769 * @param scheme Scheme name 770 * @param host Host name 771 * @param path Path 772 * @param fragment Fragment 773 * 774 * @throws URISyntaxException 775 * If the URI string constructed from the given components 776 * violates RFC 2396 777 */ 778 public URI(String scheme, String host, String path, String fragment) 779 throws URISyntaxException 780 { 781 this(scheme, null, host, -1, path, null, fragment); 782 } 783 784 /** 785 * Constructs a URI from the given components. 786 * 787 * <p> A component may be left undefined by passing <tt>null</tt>. 788 * 789 * <p> This constructor first builds a URI in string form using the given 790 * components as follows: </p> 791 * 792 * <ol> 793 * 794 * <li><p> Initially, the result string is empty. </p></li> 795 * 796 * <li><p> If a scheme is given then it is appended to the result, 797 * followed by a colon character (<tt>':'</tt>). </p></li> 798 * 799 * <li><p> If a scheme-specific part is given then it is appended. Any 800 * character that is not a <a href="#legal-chars">legal URI character</a> 801 * is <a href="#quote">quoted</a>. </p></li> 802 * 803 * <li><p> Finally, if a fragment is given then a hash character 804 * (<tt>'#'</tt>) is appended to the string, followed by the fragment. 805 * Any character that is not a legal URI character is quoted. </p></li> 806 * 807 * </ol> 808 * 809 * <p> The resulting URI string is then parsed in order to create the new 810 * URI instance as if by invoking the {@link #URI(String)} constructor; 811 * this may cause a {@link URISyntaxException} to be thrown. </p> 812 * 813 * @param scheme Scheme name 814 * @param ssp Scheme-specific part 815 * @param fragment Fragment 816 * 817 * @throws URISyntaxException 818 * If the URI string constructed from the given components 819 * violates RFC 2396 820 */ 821 public URI(String scheme, String ssp, String fragment) 822 throws URISyntaxException 823 { 824 new Parser(toString(scheme, ssp, 825 null, null, null, -1, 826 null, null, fragment)) 827 .parse(false); 828 } 829 830 /** 831 * Creates a URI by parsing the given string. 832 * 833 * <p> This convenience factory method works as if by invoking the {@link 834 * #URI(String)} constructor; any {@link URISyntaxException} thrown by the 835 * constructor is caught and wrapped in a new {@link 836 * IllegalArgumentException} object, which is then thrown. 837 * 838 * <p> This method is provided for use in situations where it is known that 839 * the given string is a legal URI, for example for URI constants declared 840 * within in a program, and so it would be considered a programming error 841 * for the string not to parse as such. The constructors, which throw 842 * {@link URISyntaxException} directly, should be used situations where a 843 * URI is being constructed from user input or from some other source that 844 * may be prone to errors. </p> 845 * 846 * @param str The string to be parsed into a URI 847 * @return The new URI 848 * 849 * @throws NullPointerException 850 * If <tt>str</tt> is <tt>null</tt> 851 * 852 * @throws IllegalArgumentException 853 * If the given string violates RFC 2396 854 */ 855 public static URI create(String str) { 856 try { 857 return new URI(str); 858 } catch (URISyntaxException x) { 859 throw new IllegalArgumentException(x.getMessage(), x); 860 } 861 } 862 863 864 // -- Operations -- 865 866 /** 867 * Attempts to parse this URI's authority component, if defined, into 868 * user-information, host, and port components. 869 * 870 * <p> If this URI's authority component has already been recognized as 871 * being server-based then it will already have been parsed into 872 * user-information, host, and port components. In this case, or if this 873 * URI has no authority component, this method simply returns this URI. 874 * 875 * <p> Otherwise this method attempts once more to parse the authority 876 * component into user-information, host, and port components, and throws 877 * an exception describing why the authority component could not be parsed 878 * in that way. 879 * 880 * <p> This method is provided because the generic URI syntax specified in 881 * <a href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a> 882 * cannot always distinguish a malformed server-based authority from a 883 * legitimate registry-based authority. It must therefore treat some 884 * instances of the former as instances of the latter. The authority 885 * component in the URI string <tt>"//foo:bar"</tt>, for example, is not a 886 * legal server-based authority but it is legal as a registry-based 887 * authority. 888 * 889 * <p> In many common situations, for example when working URIs that are 890 * known to be either URNs or URLs, the hierarchical URIs being used will 891 * always be server-based. They therefore must either be parsed as such or 892 * treated as an error. In these cases a statement such as 893 * 894 * <blockquote> 895 * <tt>URI </tt><i>u</i><tt> = new URI(str).parseServerAuthority();</tt> 896 * </blockquote> 897 * 898 * <p> can be used to ensure that <i>u</i> always refers to a URI that, if 899 * it has an authority component, has a server-based authority with proper 900 * user-information, host, and port components. Invoking this method also 901 * ensures that if the authority could not be parsed in that way then an 902 * appropriate diagnostic message can be issued based upon the exception 903 * that is thrown. </p> 904 * 905 * @return A URI whose authority field has been parsed 906 * as a server-based authority 907 * 908 * @throws URISyntaxException 909 * If the authority component of this URI is defined 910 * but cannot be parsed as a server-based authority 911 * according to RFC 2396 912 */ 913 public URI parseServerAuthority() 914 throws URISyntaxException 915 { 916 // We could be clever and cache the error message and index from the 917 // exception thrown during the original parse, but that would require 918 // either more fields or a more-obscure representation. 919 if ((host != null) || (authority == null)) 920 return this; 921 defineString(); 922 new Parser(string).parse(true); 923 return this; 924 } 925 926 /** 927 * Normalizes this URI's path. 928 * 929 * <p> If this URI is opaque, or if its path is already in normal form, 930 * then this URI is returned. Otherwise a new URI is constructed that is 931 * identical to this URI except that its path is computed by normalizing 932 * this URI's path in a manner consistent with <a 933 * href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>, 934 * section 5.2, step 6, sub-steps c through f; that is: 935 * </p> 936 * 937 * <ol> 938 * 939 * <li><p> All <tt>"."</tt> segments are removed. </p></li> 940 * 941 * <li><p> If a <tt>".."</tt> segment is preceded by a non-<tt>".."</tt> 942 * segment then both of these segments are removed. This step is 943 * repeated until it is no longer applicable. </p></li> 944 * 945 * <li><p> If the path is relative, and if its first segment contains a 946 * colon character (<tt>':'</tt>), then a <tt>"."</tt> segment is 947 * prepended. This prevents a relative URI with a path such as 948 * <tt>"a:b/c/d"</tt> from later being re-parsed as an opaque URI with a 949 * scheme of <tt>"a"</tt> and a scheme-specific part of <tt>"b/c/d"</tt>. 950 * <b><i>(Deviation from RFC 2396)</i></b> </p></li> 951 * 952 * </ol> 953 * 954 * <p> A normalized path will begin with one or more <tt>".."</tt> segments 955 * if there were insufficient non-<tt>".."</tt> segments preceding them to 956 * allow their removal. A normalized path will begin with a <tt>"."</tt> 957 * segment if one was inserted by step 3 above. Otherwise, a normalized 958 * path will not contain any <tt>"."</tt> or <tt>".."</tt> segments. </p> 959 * 960 * @return A URI equivalent to this URI, 961 * but whose path is in normal form 962 */ 963 public URI normalize() { 964 return normalize(this); 965 } 966 967 /** 968 * Resolves the given URI against this URI. 969 * 970 * <p> If the given URI is already absolute, or if this URI is opaque, then 971 * the given URI is returned. 972 * 973 * <p><a name="resolve-frag"></a> If the given URI's fragment component is 974 * defined, its path component is empty, and its scheme, authority, and 975 * query components are undefined, then a URI with the given fragment but 976 * with all other components equal to those of this URI is returned. This 977 * allows a URI representing a standalone fragment reference, such as 978 * <tt>"#foo"</tt>, to be usefully resolved against a base URI. 979 * 980 * <p> Otherwise this method constructs a new hierarchical URI in a manner 981 * consistent with <a 982 * href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>, 983 * section 5.2; that is: </p> 984 * 985 * <ol> 986 * 987 * <li><p> A new URI is constructed with this URI's scheme and the given 988 * URI's query and fragment components. </p></li> 989 * 990 * <li><p> If the given URI has an authority component then the new URI's 991 * authority and path are taken from the given URI. </p></li> 992 * 993 * <li><p> Otherwise the new URI's authority component is copied from 994 * this URI, and its path is computed as follows: </p> 995 * 996 * <ol type=a> 997 * 998 * <li><p> If the given URI's path is absolute then the new URI's path 999 * is taken from the given URI. </p></li> 1000 * 1001 * <li><p> Otherwise the given URI's path is relative, and so the new 1002 * URI's path is computed by resolving the path of the given URI 1003 * against the path of this URI. This is done by concatenating all but 1004 * the last segment of this URI's path, if any, with the given URI's 1005 * path and then normalizing the result as if by invoking the {@link 1006 * #normalize() normalize} method. </p></li> 1007 * 1008 * </ol></li> 1009 * 1010 * </ol> 1011 * 1012 * <p> The result of this method is absolute if, and only if, either this 1013 * URI is absolute or the given URI is absolute. </p> 1014 * 1015 * @param uri The URI to be resolved against this URI 1016 * @return The resulting URI 1017 * 1018 * @throws NullPointerException 1019 * If <tt>uri</tt> is <tt>null</tt> 1020 */ 1021 public URI resolve(URI uri) { 1022 return resolve(this, uri); 1023 } 1024 1025 /** 1026 * Constructs a new URI by parsing the given string and then resolving it 1027 * against this URI. 1028 * 1029 * <p> This convenience method works as if invoking it were equivalent to 1030 * evaluating the expression <tt>{@link #resolve(java.net.URI) 1031 * resolve}(URI.{@link #create(String) create}(str))</tt>. </p> 1032 * 1033 * @param str The string to be parsed into a URI 1034 * @return The resulting URI 1035 * 1036 * @throws NullPointerException 1037 * If <tt>str</tt> is <tt>null</tt> 1038 * 1039 * @throws IllegalArgumentException 1040 * If the given string violates RFC 2396 1041 */ 1042 public URI resolve(String str) { 1043 return resolve(URI.create(str)); 1044 } 1045 1046 /** 1047 * Relativizes the given URI against this URI. 1048 * 1049 * <p> The relativization of the given URI against this URI is computed as 1050 * follows: </p> 1051 * 1052 * <ol> 1053 * 1054 * <li><p> If either this URI or the given URI are opaque, or if the 1055 * scheme and authority components of the two URIs are not identical, or 1056 * if the path of this URI is not a prefix of the path of the given URI, 1057 * then the given URI is returned. </p></li> 1058 * 1059 * <li><p> Otherwise a new relative hierarchical URI is constructed with 1060 * query and fragment components taken from the given URI and with a path 1061 * component computed by removing this URI's path from the beginning of 1062 * the given URI's path. </p></li> 1063 * 1064 * </ol> 1065 * 1066 * @param uri The URI to be relativized against this URI 1067 * @return The resulting URI 1068 * 1069 * @throws NullPointerException 1070 * If <tt>uri</tt> is <tt>null</tt> 1071 */ 1072 public URI relativize(URI uri) { 1073 return relativize(this, uri); 1074 } 1075 1076 /** 1077 * Constructs a URL from this URI. 1078 * 1079 * <p> This convenience method works as if invoking it were equivalent to 1080 * evaluating the expression <tt>new URL(this.toString())</tt> after 1081 * first checking that this URI is absolute. </p> 1082 * 1083 * @return A URL constructed from this URI 1084 * 1085 * @throws IllegalArgumentException 1086 * If this URL is not absolute 1087 * 1088 * @throws MalformedURLException 1089 * If a protocol handler for the URL could not be found, 1090 * or if some other error occurred while constructing the URL 1091 */ 1092 public URL toURL() 1093 throws MalformedURLException { 1094 if (!isAbsolute()) 1095 throw new IllegalArgumentException("URI is not absolute"); 1096 return new URL(toString()); 1097 } 1098 1099 // -- Component access methods -- 1100 1101 /** 1102 * Returns the scheme component of this URI. 1103 * 1104 * <p> The scheme component of a URI, if defined, only contains characters 1105 * in the <i>alphanum</i> category and in the string <tt>"-.+"</tt>. A 1106 * scheme always starts with an <i>alpha</i> character. <p> 1107 * 1108 * The scheme component of a URI cannot contain escaped octets, hence this 1109 * method does not perform any decoding. 1110 * 1111 * @return The scheme component of this URI, 1112 * or <tt>null</tt> if the scheme is undefined 1113 */ 1114 public String getScheme() { 1115 return scheme; 1116 } 1117 1118 /** 1119 * Tells whether or not this URI is absolute. 1120 * 1121 * <p> A URI is absolute if, and only if, it has a scheme component. </p> 1122 * 1123 * @return <tt>true</tt> if, and only if, this URI is absolute 1124 */ 1125 public boolean isAbsolute() { 1126 return scheme != null; 1127 } 1128 1129 /** 1130 * Tells whether or not this URI is opaque. 1131 * 1132 * <p> A URI is opaque if, and only if, it is absolute and its 1133 * scheme-specific part does not begin with a slash character ('/'). 1134 * An opaque URI has a scheme, a scheme-specific part, and possibly 1135 * a fragment; all other components are undefined. </p> 1136 * 1137 * @return <tt>true</tt> if, and only if, this URI is opaque 1138 */ 1139 public boolean isOpaque() { 1140 return path == null; 1141 } 1142 1143 /** 1144 * Returns the raw scheme-specific part of this URI. The scheme-specific 1145 * part is never undefined, though it may be empty. 1146 * 1147 * <p> The scheme-specific part of a URI only contains legal URI 1148 * characters. </p> 1149 * 1150 * @return The raw scheme-specific part of this URI 1151 * (never <tt>null</tt>) 1152 */ 1153 public String getRawSchemeSpecificPart() { 1154 defineSchemeSpecificPart(); 1155 return schemeSpecificPart; 1156 } 1157 1158 /** 1159 * Returns the decoded scheme-specific part of this URI. 1160 * 1161 * <p> The string returned by this method is equal to that returned by the 1162 * {@link #getRawSchemeSpecificPart() getRawSchemeSpecificPart} method 1163 * except that all sequences of escaped octets are <a 1164 * href="#decode">decoded</a>. </p> 1165 * 1166 * @return The decoded scheme-specific part of this URI 1167 * (never <tt>null</tt>) 1168 */ 1169 public String getSchemeSpecificPart() { 1170 if (decodedSchemeSpecificPart == null) 1171 decodedSchemeSpecificPart = decode(getRawSchemeSpecificPart()); 1172 return decodedSchemeSpecificPart; 1173 } 1174 1175 /** 1176 * Returns the raw authority component of this URI. 1177 * 1178 * <p> The authority component of a URI, if defined, only contains the 1179 * commercial-at character (<tt>'@'</tt>) and characters in the 1180 * <i>unreserved</i>, <i>punct</i>, <i>escaped</i>, and <i>other</i> 1181 * categories. If the authority is server-based then it is further 1182 * constrained to have valid user-information, host, and port 1183 * components. </p> 1184 * 1185 * @return The raw authority component of this URI, 1186 * or <tt>null</tt> if the authority is undefined 1187 */ 1188 public String getRawAuthority() { 1189 return authority; 1190 } 1191 1192 /** 1193 * Returns the decoded authority component of this URI. 1194 * 1195 * <p> The string returned by this method is equal to that returned by the 1196 * {@link #getRawAuthority() getRawAuthority} method except that all 1197 * sequences of escaped octets are <a href="#decode">decoded</a>. </p> 1198 * 1199 * @return The decoded authority component of this URI, 1200 * or <tt>null</tt> if the authority is undefined 1201 */ 1202 public String getAuthority() { 1203 if (decodedAuthority == null) 1204 decodedAuthority = decode(authority); 1205 return decodedAuthority; 1206 } 1207 1208 /** 1209 * Returns the raw user-information component of this URI. 1210 * 1211 * <p> The user-information component of a URI, if defined, only contains 1212 * characters in the <i>unreserved</i>, <i>punct</i>, <i>escaped</i>, and 1213 * <i>other</i> categories. </p> 1214 * 1215 * @return The raw user-information component of this URI, 1216 * or <tt>null</tt> if the user information is undefined 1217 */ 1218 public String getRawUserInfo() { 1219 return userInfo; 1220 } 1221 1222 /** 1223 * Returns the decoded user-information component of this URI. 1224 * 1225 * <p> The string returned by this method is equal to that returned by the 1226 * {@link #getRawUserInfo() getRawUserInfo} method except that all 1227 * sequences of escaped octets are <a href="#decode">decoded</a>. </p> 1228 * 1229 * @return The decoded user-information component of this URI, 1230 * or <tt>null</tt> if the user information is undefined 1231 */ 1232 public String getUserInfo() { 1233 if ((decodedUserInfo == null) && (userInfo != null)) 1234 decodedUserInfo = decode(userInfo); 1235 return decodedUserInfo; 1236 } 1237 1238 /** 1239 * Returns the host component of this URI. 1240 * 1241 * <p> The host component of a URI, if defined, will have one of the 1242 * following forms: </p> 1243 * 1244 * <ul type=disc> 1245 * 1246 * <li><p> A domain name consisting of one or more <i>labels</i> 1247 * separated by period characters (<tt>'.'</tt>), optionally followed by 1248 * a period character. Each label consists of <i>alphanum</i> characters 1249 * as well as hyphen characters (<tt>'-'</tt>), though hyphens never 1250 * occur as the first or last characters in a label. The rightmost 1251 * label of a domain name consisting of two or more labels, begins 1252 * with an <i>alpha</i> character. </li> 1253 * 1254 * <li><p> A dotted-quad IPv4 address of the form 1255 * <i>digit</i><tt>+.</tt><i>digit</i><tt>+.</tt><i>digit</i><tt>+.</tt><i>digit</i><tt>+</tt>, 1256 * where no <i>digit</i> sequence is longer than three characters and no 1257 * sequence has a value larger than 255. </p></li> 1258 * 1259 * <li><p> An IPv6 address enclosed in square brackets (<tt>'['</tt> and 1260 * <tt>']'</tt>) and consisting of hexadecimal digits, colon characters 1261 * (<tt>':'</tt>), and possibly an embedded IPv4 address. The full 1262 * syntax of IPv6 addresses is specified in <a 1263 * href="http://www.ietf.org/rfc/rfc2373.txt"><i>RFC 2373: IPv6 1264 * Addressing Architecture</i></a>. </p></li> 1265 * 1266 * </ul> 1267 * 1268 * The host component of a URI cannot contain escaped octets, hence this 1269 * method does not perform any decoding. 1270 * 1271 * @return The host component of this URI, 1272 * or <tt>null</tt> if the host is undefined 1273 */ 1274 public String getHost() { 1275 return host; 1276 } 1277 1278 /** 1279 * Returns the port number of this URI. 1280 * 1281 * <p> The port component of a URI, if defined, is a non-negative 1282 * integer. </p> 1283 * 1284 * @return The port component of this URI, 1285 * or <tt>-1</tt> if the port is undefined 1286 */ 1287 public int getPort() { 1288 return port; 1289 } 1290 1291 /** 1292 * Returns the raw path component of this URI. 1293 * 1294 * <p> The path component of a URI, if defined, only contains the slash 1295 * character (<tt>'/'</tt>), the commercial-at character (<tt>'@'</tt>), 1296 * and characters in the <i>unreserved</i>, <i>punct</i>, <i>escaped</i>, 1297 * and <i>other</i> categories. </p> 1298 * 1299 * @return The path component of this URI, 1300 * or <tt>null</tt> if the path is undefined 1301 */ 1302 public String getRawPath() { 1303 return path; 1304 } 1305 1306 /** 1307 * Returns the decoded path component of this URI. 1308 * 1309 * <p> The string returned by this method is equal to that returned by the 1310 * {@link #getRawPath() getRawPath} method except that all sequences of 1311 * escaped octets are <a href="#decode">decoded</a>. </p> 1312 * 1313 * @return The decoded path component of this URI, 1314 * or <tt>null</tt> if the path is undefined 1315 */ 1316 public String getPath() { 1317 if ((decodedPath == null) && (path != null)) 1318 decodedPath = decode(path); 1319 return decodedPath; 1320 } 1321 1322 /** 1323 * Returns the raw query component of this URI. 1324 * 1325 * <p> The query component of a URI, if defined, only contains legal URI 1326 * characters. </p> 1327 * 1328 * @return The raw query component of this URI, 1329 * or <tt>null</tt> if the query is undefined 1330 */ 1331 public String getRawQuery() { 1332 return query; 1333 } 1334 1335 /** 1336 * Returns the decoded query component of this URI. 1337 * 1338 * <p> The string returned by this method is equal to that returned by the 1339 * {@link #getRawQuery() getRawQuery} method except that all sequences of 1340 * escaped octets are <a href="#decode">decoded</a>. </p> 1341 * 1342 * @return The decoded query component of this URI, 1343 * or <tt>null</tt> if the query is undefined 1344 */ 1345 public String getQuery() { 1346 if ((decodedQuery == null) && (query != null)) 1347 decodedQuery = decode(query); 1348 return decodedQuery; 1349 } 1350 1351 /** 1352 * Returns the raw fragment component of this URI. 1353 * 1354 * <p> The fragment component of a URI, if defined, only contains legal URI 1355 * characters. </p> 1356 * 1357 * @return The raw fragment component of this URI, 1358 * or <tt>null</tt> if the fragment is undefined 1359 */ 1360 public String getRawFragment() { 1361 return fragment; 1362 } 1363 1364 /** 1365 * Returns the decoded fragment component of this URI. 1366 * 1367 * <p> The string returned by this method is equal to that returned by the 1368 * {@link #getRawFragment() getRawFragment} method except that all 1369 * sequences of escaped octets are <a href="#decode">decoded</a>. </p> 1370 * 1371 * @return The decoded fragment component of this URI, 1372 * or <tt>null</tt> if the fragment is undefined 1373 */ 1374 public String getFragment() { 1375 if ((decodedFragment == null) && (fragment != null)) 1376 decodedFragment = decode(fragment); 1377 return decodedFragment; 1378 } 1379 1380 1381 // -- Equality, comparison, hash code, toString, and serialization -- 1382 1383 /** 1384 * Tests this URI for equality with another object. 1385 * 1386 * <p> If the given object is not a URI then this method immediately 1387 * returns <tt>false</tt>. 1388 * 1389 * <p> For two URIs to be considered equal requires that either both are 1390 * opaque or both are hierarchical. Their schemes must either both be 1391 * undefined or else be equal without regard to case. Their fragments 1392 * must either both be undefined or else be equal. 1393 * 1394 * <p> For two opaque URIs to be considered equal, their scheme-specific 1395 * parts must be equal. 1396 * 1397 * <p> For two hierarchical URIs to be considered equal, their paths must 1398 * be equal and their queries must either both be undefined or else be 1399 * equal. Their authorities must either both be undefined, or both be 1400 * registry-based, or both be server-based. If their authorities are 1401 * defined and are registry-based, then they must be equal. If their 1402 * authorities are defined and are server-based, then their hosts must be 1403 * equal without regard to case, their port numbers must be equal, and 1404 * their user-information components must be equal. 1405 * 1406 * <p> When testing the user-information, path, query, fragment, authority, 1407 * or scheme-specific parts of two URIs for equality, the raw forms rather 1408 * than the encoded forms of these components are compared and the 1409 * hexadecimal digits of escaped octets are compared without regard to 1410 * case. 1411 * 1412 * <p> This method satisfies the general contract of the {@link 1413 * java.lang.Object#equals(Object) Object.equals} method. </p> 1414 * 1415 * @param ob The object to which this object is to be compared 1416 * 1417 * @return <tt>true</tt> if, and only if, the given object is a URI that 1418 * is identical to this URI 1419 */ 1420 public boolean equals(Object ob) { 1421 if (ob == this) 1422 return true; 1423 if (!(ob instanceof URI)) 1424 return false; 1425 URI that = (URI)ob; 1426 if (this.isOpaque() != that.isOpaque()) return false; 1427 if (!equalIgnoringCase(this.scheme, that.scheme)) return false; 1428 if (!equal(this.fragment, that.fragment)) return false; 1429 1430 // Opaque 1431 if (this.isOpaque()) 1432 return equal(this.schemeSpecificPart, that.schemeSpecificPart); 1433 1434 // Hierarchical 1435 if (!equal(this.path, that.path)) return false; 1436 if (!equal(this.query, that.query)) return false; 1437 1438 // Authorities 1439 if (this.authority == that.authority) return true; 1440 if (this.host != null) { 1441 // Server-based 1442 if (!equal(this.userInfo, that.userInfo)) return false; 1443 if (!equalIgnoringCase(this.host, that.host)) return false; 1444 if (this.port != that.port) return false; 1445 } else if (this.authority != null) { 1446 // Registry-based 1447 if (!equal(this.authority, that.authority)) return false; 1448 } else if (this.authority != that.authority) { 1449 return false; 1450 } 1451 1452 return true; 1453 } 1454 1455 /** 1456 * Returns a hash-code value for this URI. The hash code is based upon all 1457 * of the URI's components, and satisfies the general contract of the 1458 * {@link java.lang.Object#hashCode() Object.hashCode} method. 1459 * 1460 * @return A hash-code value for this URI 1461 */ 1462 public int hashCode() { 1463 if (hash != 0) 1464 return hash; 1465 int h = hashIgnoringCase(0, scheme); 1466 h = hash(h, fragment); 1467 if (isOpaque()) { 1468 h = hash(h, schemeSpecificPart); 1469 } else { 1470 h = hash(h, path); 1471 h = hash(h, query); 1472 if (host != null) { 1473 h = hash(h, userInfo); 1474 h = hashIgnoringCase(h, host); 1475 h += 1949 * port; 1476 } else { 1477 h = hash(h, authority); 1478 } 1479 } 1480 hash = h; 1481 return h; 1482 } 1483 1484 /** 1485 * Compares this URI to another object, which must be a URI. 1486 * 1487 * <p> When comparing corresponding components of two URIs, if one 1488 * component is undefined but the other is defined then the first is 1489 * considered to be less than the second. Unless otherwise noted, string 1490 * components are ordered according to their natural, case-sensitive 1491 * ordering as defined by the {@link java.lang.String#compareTo(Object) 1492 * String.compareTo} method. String components that are subject to 1493 * encoding are compared by comparing their raw forms rather than their 1494 * encoded forms. 1495 * 1496 * <p> The ordering of URIs is defined as follows: </p> 1497 * 1498 * <ul type=disc> 1499 * 1500 * <li><p> Two URIs with different schemes are ordered according the 1501 * ordering of their schemes, without regard to case. </p></li> 1502 * 1503 * <li><p> A hierarchical URI is considered to be less than an opaque URI 1504 * with an identical scheme. </p></li> 1505 * 1506 * <li><p> Two opaque URIs with identical schemes are ordered according 1507 * to the ordering of their scheme-specific parts. </p></li> 1508 * 1509 * <li><p> Two opaque URIs with identical schemes and scheme-specific 1510 * parts are ordered according to the ordering of their 1511 * fragments. </p></li> 1512 * 1513 * <li><p> Two hierarchical URIs with identical schemes are ordered 1514 * according to the ordering of their authority components: </p> 1515 * 1516 * <ul type=disc> 1517 * 1518 * <li><p> If both authority components are server-based then the URIs 1519 * are ordered according to their user-information components; if these 1520 * components are identical then the URIs are ordered according to the 1521 * ordering of their hosts, without regard to case; if the hosts are 1522 * identical then the URIs are ordered according to the ordering of 1523 * their ports. </p></li> 1524 * 1525 * <li><p> If one or both authority components are registry-based then 1526 * the URIs are ordered according to the ordering of their authority 1527 * components. </p></li> 1528 * 1529 * </ul></li> 1530 * 1531 * <li><p> Finally, two hierarchical URIs with identical schemes and 1532 * authority components are ordered according to the ordering of their 1533 * paths; if their paths are identical then they are ordered according to 1534 * the ordering of their queries; if the queries are identical then they 1535 * are ordered according to the order of their fragments. </p></li> 1536 * 1537 * </ul> 1538 * 1539 * <p> This method satisfies the general contract of the {@link 1540 * java.lang.Comparable#compareTo(Object) Comparable.compareTo} 1541 * method. </p> 1542 * 1543 * @param that 1544 * The object to which this URI is to be compared 1545 * 1546 * @return A negative integer, zero, or a positive integer as this URI is 1547 * less than, equal to, or greater than the given URI 1548 * 1549 * @throws ClassCastException 1550 * If the given object is not a URI 1551 */ 1552 public int compareTo(URI that) { 1553 int c; 1554 1555 if ((c = compareIgnoringCase(this.scheme, that.scheme)) != 0) 1556 return c; 1557 1558 if (this.isOpaque()) { 1559 if (that.isOpaque()) { 1560 // Both opaque 1561 if ((c = compare(this.schemeSpecificPart, 1562 that.schemeSpecificPart)) != 0) 1563 return c; 1564 return compare(this.fragment, that.fragment); 1565 } 1566 return +1; // Opaque > hierarchical 1567 } else if (that.isOpaque()) { 1568 return -1; // Hierarchical < opaque 1569 } 1570 1571 // Hierarchical 1572 if ((this.host != null) && (that.host != null)) { 1573 // Both server-based 1574 if ((c = compare(this.userInfo, that.userInfo)) != 0) 1575 return c; 1576 if ((c = compareIgnoringCase(this.host, that.host)) != 0) 1577 return c; 1578 if ((c = this.port - that.port) != 0) 1579 return c; 1580 } else { 1581 // If one or both authorities are registry-based then we simply 1582 // compare them in the usual, case-sensitive way. If one is 1583 // registry-based and one is server-based then the strings are 1584 // guaranteed to be unequal, hence the comparison will never return 1585 // zero and the compareTo and equals methods will remain 1586 // consistent. 1587 if ((c = compare(this.authority, that.authority)) != 0) return c; 1588 } 1589 1590 if ((c = compare(this.path, that.path)) != 0) return c; 1591 if ((c = compare(this.query, that.query)) != 0) return c; 1592 return compare(this.fragment, that.fragment); 1593 } 1594 1595 /** 1596 * Returns the content of this URI as a string. 1597 * 1598 * <p> If this URI was created by invoking one of the constructors in this 1599 * class then a string equivalent to the original input string, or to the 1600 * string computed from the originally-given components, as appropriate, is 1601 * returned. Otherwise this URI was created by normalization, resolution, 1602 * or relativization, and so a string is constructed from this URI's 1603 * components according to the rules specified in <a 1604 * href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>, 1605 * section 5.2, step 7. </p> 1606 * 1607 * @return The string form of this URI 1608 */ 1609 public String toString() { 1610 defineString(); 1611 return string; 1612 } 1613 1614 /** 1615 * Returns the content of this URI as a US-ASCII string. 1616 * 1617 * <p> If this URI does not contain any characters in the <i>other</i> 1618 * category then an invocation of this method will return the same value as 1619 * an invocation of the {@link #toString() toString} method. Otherwise 1620 * this method works as if by invoking that method and then <a 1621 * href="#encode">encoding</a> the result. </p> 1622 * 1623 * @return The string form of this URI, encoded as needed 1624 * so that it only contains characters in the US-ASCII 1625 * charset 1626 */ 1627 public String toASCIIString() { 1628 defineString(); 1629 return encode(string); 1630 } 1631 1632 1633 // -- Serialization support -- 1634 1635 /** 1636 * Saves the content of this URI to the given serial stream. 1637 * 1638 * <p> The only serializable field of a URI instance is its <tt>string</tt> 1639 * field. That field is given a value, if it does not have one already, 1640 * and then the {@link java.io.ObjectOutputStream#defaultWriteObject()} 1641 * method of the given object-output stream is invoked. </p> 1642 * 1643 * @param os The object-output stream to which this object 1644 * is to be written 1645 */ 1646 private void writeObject(ObjectOutputStream os) 1647 throws IOException 1648 { 1649 defineString(); 1650 os.defaultWriteObject(); // Writes the string field only 1651 } 1652 1653 /** 1654 * Reconstitutes a URI from the given serial stream. 1655 * 1656 * <p> The {@link java.io.ObjectInputStream#defaultReadObject()} method is 1657 * invoked to read the value of the <tt>string</tt> field. The result is 1658 * then parsed in the usual way. 1659 * 1660 * @param is The object-input stream from which this object 1661 * is being read 1662 */ 1663 private void readObject(ObjectInputStream is) 1664 throws ClassNotFoundException, IOException 1665 { 1666 port = -1; // Argh 1667 is.defaultReadObject(); 1668 try { 1669 new Parser(string).parse(false); 1670 } catch (URISyntaxException x) { 1671 IOException y = new InvalidObjectException("Invalid URI"); 1672 y.initCause(x); 1673 throw y; 1674 } 1675 } 1676 1677 1678 // -- End of public methods -- 1679 1680 1681 // -- Utility methods for string-field comparison and hashing -- 1682 1683 // These methods return appropriate values for null string arguments, 1684 // thereby simplifying the equals, hashCode, and compareTo methods. 1685 // 1686 // The case-ignoring methods should only be applied to strings whose 1687 // characters are all known to be US-ASCII. Because of this restriction, 1688 // these methods are faster than the similar methods in the String class. 1689 1690 // US-ASCII only 1691 private static int toLower(char c) { 1692 if ((c >= 'A') && (c <= 'Z')) 1693 return c + ('a' - 'A'); 1694 return c; 1695 } 1696 1697 private static boolean equal(String s, String t) { 1698 if (s == t) return true; 1699 if ((s != null) && (t != null)) { 1700 if (s.length() != t.length()) 1701 return false; 1702 if (s.indexOf('%') < 0) 1703 return s.equals(t); 1704 int n = s.length(); 1705 for (int i = 0; i < n;) { 1706 char c = s.charAt(i); 1707 char d = t.charAt(i); 1708 if (c != '%') { 1709 if (c != d) 1710 return false; 1711 i++; 1712 continue; 1713 } 1714 i++; 1715 if (toLower(s.charAt(i)) != toLower(t.charAt(i))) 1716 return false; 1717 i++; 1718 if (toLower(s.charAt(i)) != toLower(t.charAt(i))) 1719 return false; 1720 i++; 1721 } 1722 return true; 1723 } 1724 return false; 1725 } 1726 1727 // US-ASCII only 1728 private static boolean equalIgnoringCase(String s, String t) { 1729 if (s == t) return true; 1730 if ((s != null) && (t != null)) { 1731 int n = s.length(); 1732 if (t.length() != n) 1733 return false; 1734 for (int i = 0; i < n; i++) { 1735 if (toLower(s.charAt(i)) != toLower(t.charAt(i))) 1736 return false; 1737 } 1738 return true; 1739 } 1740 return false; 1741 } 1742 1743 private static int hash(int hash, String s) { 1744 if (s == null) return hash; 1745 return hash * 127 + s.hashCode(); 1746 } 1747 1748 // US-ASCII only 1749 private static int hashIgnoringCase(int hash, String s) { 1750 if (s == null) return hash; 1751 int h = hash; 1752 int n = s.length(); 1753 for (int i = 0; i < n; i++) 1754 h = 31 * h + toLower(s.charAt(i)); 1755 return h; 1756 } 1757 1758 private static int compare(String s, String t) { 1759 if (s == t) return 0; 1760 if (s != null) { 1761 if (t != null) 1762 return s.compareTo(t); 1763 else 1764 return +1; 1765 } else { 1766 return -1; 1767 } 1768 } 1769 1770 // US-ASCII only 1771 private static int compareIgnoringCase(String s, String t) { 1772 if (s == t) return 0; 1773 if (s != null) { 1774 if (t != null) { 1775 int sn = s.length(); 1776 int tn = t.length(); 1777 int n = sn < tn ? sn : tn; 1778 for (int i = 0; i < n; i++) { 1779 int c = toLower(s.charAt(i)) - toLower(t.charAt(i)); 1780 if (c != 0) 1781 return c; 1782 } 1783 return sn - tn; 1784 } 1785 return +1; 1786 } else { 1787 return -1; 1788 } 1789 } 1790 1791 1792 // -- String construction -- 1793 1794 // If a scheme is given then the path, if given, must be absolute 1795 // 1796 private static void checkPath(String s, String scheme, String path) 1797 throws URISyntaxException 1798 { 1799 if (scheme != null) { 1800 if ((path != null) 1801 && ((path.length() > 0) && (path.charAt(0) != '/'))) 1802 throw new URISyntaxException(s, 1803 "Relative path in absolute URI"); 1804 } 1805 } 1806 1807 private void appendAuthority(StringBuffer sb, 1808 String authority, 1809 String userInfo, 1810 String host, 1811 int port) 1812 { 1813 if (host != null) { 1814 sb.append("//"); 1815 if (userInfo != null) { 1816 sb.append(quote(userInfo, L_USERINFO, H_USERINFO)); 1817 sb.append('@'); 1818 } 1819 boolean needBrackets = ((host.indexOf(':') >= 0) 1820 && !host.startsWith("[") 1821 && !host.endsWith("]")); 1822 if (needBrackets) sb.append('['); 1823 sb.append(host); 1824 if (needBrackets) sb.append(']'); 1825 if (port != -1) { 1826 sb.append(':'); 1827 sb.append(port); 1828 } 1829 } else if (authority != null) { 1830 sb.append("//"); 1831 if (authority.startsWith("[")) { 1832 // authority should (but may not) contain an embedded IPv6 address 1833 int end = authority.indexOf("]"); 1834 String doquote = authority, dontquote = ""; 1835 if (end != -1 && authority.indexOf(":") != -1) { 1836 // the authority contains an IPv6 address 1837 if (end == authority.length()) { 1838 dontquote = authority; 1839 doquote = ""; 1840 } else { 1841 dontquote = authority.substring(0 , end + 1); 1842 doquote = authority.substring(end + 1); 1843 } 1844 } 1845 sb.append(dontquote); 1846 sb.append(quote(doquote, 1847 L_REG_NAME | L_SERVER, 1848 H_REG_NAME | H_SERVER)); 1849 } else { 1850 sb.append(quote(authority, 1851 L_REG_NAME | L_SERVER, 1852 H_REG_NAME | H_SERVER)); 1853 } 1854 } 1855 } 1856 1857 private void appendSchemeSpecificPart(StringBuffer sb, 1858 String opaquePart, 1859 String authority, 1860 String userInfo, 1861 String host, 1862 int port, 1863 String path, 1864 String query) 1865 { 1866 if (opaquePart != null) { 1867 /* check if SSP begins with an IPv6 address 1868 * because we must not quote a literal IPv6 address 1869 */ 1870 if (opaquePart.startsWith("//[")) { 1871 int end = opaquePart.indexOf("]"); 1872 if (end != -1 && opaquePart.indexOf(":")!=-1) { 1873 String doquote, dontquote; 1874 if (end == opaquePart.length()) { 1875 dontquote = opaquePart; 1876 doquote = ""; 1877 } else { 1878 dontquote = opaquePart.substring(0,end+1); 1879 doquote = opaquePart.substring(end+1); 1880 } 1881 sb.append (dontquote); 1882 sb.append(quote(doquote, L_URIC, H_URIC)); 1883 } 1884 } else { 1885 sb.append(quote(opaquePart, L_URIC, H_URIC)); 1886 } 1887 } else { 1888 appendAuthority(sb, authority, userInfo, host, port); 1889 if (path != null) 1890 sb.append(quote(path, L_PATH, H_PATH)); 1891 if (query != null) { 1892 sb.append('?'); 1893 sb.append(quote(query, L_URIC, H_URIC)); 1894 } 1895 } 1896 } 1897 1898 private void appendFragment(StringBuffer sb, String fragment) { 1899 if (fragment != null) { 1900 sb.append('#'); 1901 sb.append(quote(fragment, L_URIC, H_URIC)); 1902 } 1903 } 1904 1905 private String toString(String scheme, 1906 String opaquePart, 1907 String authority, 1908 String userInfo, 1909 String host, 1910 int port, 1911 String path, 1912 String query, 1913 String fragment) 1914 { 1915 StringBuffer sb = new StringBuffer(); 1916 if (scheme != null) { 1917 sb.append(scheme); 1918 sb.append(':'); 1919 } 1920 appendSchemeSpecificPart(sb, opaquePart, 1921 authority, userInfo, host, port, 1922 path, query); 1923 appendFragment(sb, fragment); 1924 return sb.toString(); 1925 } 1926 1927 private void defineSchemeSpecificPart() { 1928 if (schemeSpecificPart != null) return; 1929 StringBuffer sb = new StringBuffer(); 1930 appendSchemeSpecificPart(sb, null, getAuthority(), getUserInfo(), 1931 host, port, getPath(), getQuery()); 1932 if (sb.length() == 0) return; 1933 schemeSpecificPart = sb.toString(); 1934 } 1935 1936 private void defineString() { 1937 if (string != null) return; 1938 1939 StringBuffer sb = new StringBuffer(); 1940 if (scheme != null) { 1941 sb.append(scheme); 1942 sb.append(':'); 1943 } 1944 if (isOpaque()) { 1945 sb.append(schemeSpecificPart); 1946 } else { 1947 if (host != null) { 1948 sb.append("//"); 1949 if (userInfo != null) { 1950 sb.append(userInfo); 1951 sb.append('@'); 1952 } 1953 boolean needBrackets = ((host.indexOf(':') >= 0) 1954 && !host.startsWith("[") 1955 && !host.endsWith("]")); 1956 if (needBrackets) sb.append('['); 1957 sb.append(host); 1958 if (needBrackets) sb.append(']'); 1959 if (port != -1) { 1960 sb.append(':'); 1961 sb.append(port); 1962 } 1963 } else if (authority != null) { 1964 sb.append("//"); 1965 sb.append(authority); 1966 } 1967 if (path != null) 1968 sb.append(path); 1969 if (query != null) { 1970 sb.append('?'); 1971 sb.append(query); 1972 } 1973 } 1974 if (fragment != null) { 1975 sb.append('#'); 1976 sb.append(fragment); 1977 } 1978 string = sb.toString(); 1979 } 1980 1981 1982 // -- Normalization, resolution, and relativization -- 1983 1984 // RFC2396 5.2 (6) 1985 private static String resolvePath(String base, String child, 1986 boolean absolute) 1987 { 1988 int i = base.lastIndexOf('/'); 1989 int cn = child.length(); 1990 String path = ""; 1991 1992 if (cn == 0) { 1993 // 5.2 (6a) 1994 if (i >= 0) 1995 path = base.substring(0, i + 1); 1996 } else { 1997 StringBuffer sb = new StringBuffer(base.length() + cn); 1998 // 5.2 (6a) 1999 if (i >= 0) 2000 sb.append(base.substring(0, i + 1)); 2001 // 5.2 (6b) 2002 sb.append(child); 2003 path = sb.toString(); 2004 } 2005 2006 // 5.2 (6c-f) 2007 String np = normalize(path); 2008 2009 // 5.2 (6g): If the result is absolute but the path begins with "../", 2010 // then we simply leave the path as-is 2011 2012 return np; 2013 } 2014 2015 // RFC2396 5.2 2016 private static URI resolve(URI base, URI child) { 2017 // check if child if opaque first so that NPE is thrown 2018 // if child is null. 2019 if (child.isOpaque() || base.isOpaque()) 2020 return child; 2021 2022 // 5.2 (2): Reference to current document (lone fragment) 2023 if ((child.scheme == null) && (child.authority == null) 2024 && child.path.equals("") && (child.fragment != null) 2025 && (child.query == null)) { 2026 if ((base.fragment != null) 2027 && child.fragment.equals(base.fragment)) { 2028 return base; 2029 } 2030 URI ru = new URI(); 2031 ru.scheme = base.scheme; 2032 ru.authority = base.authority; 2033 ru.userInfo = base.userInfo; 2034 ru.host = base.host; 2035 ru.port = base.port; 2036 ru.path = base.path; 2037 ru.fragment = child.fragment; 2038 ru.query = base.query; 2039 return ru; 2040 } 2041 2042 // 5.2 (3): Child is absolute 2043 if (child.scheme != null) 2044 return child; 2045 2046 URI ru = new URI(); // Resolved URI 2047 ru.scheme = base.scheme; 2048 ru.query = child.query; 2049 ru.fragment = child.fragment; 2050 2051 // 5.2 (4): Authority 2052 if (child.authority == null) { 2053 ru.authority = base.authority; 2054 ru.host = base.host; 2055 ru.userInfo = base.userInfo; 2056 ru.port = base.port; 2057 2058 String cp = (child.path == null) ? "" : child.path; 2059 if ((cp.length() > 0) && (cp.charAt(0) == '/')) { 2060 // 5.2 (5): Child path is absolute 2061 ru.path = child.path; 2062 } else { 2063 // 5.2 (6): Resolve relative path 2064 ru.path = resolvePath(base.path, cp, base.isAbsolute()); 2065 } 2066 } else { 2067 ru.authority = child.authority; 2068 ru.host = child.host; 2069 ru.userInfo = child.userInfo; 2070 ru.host = child.host; 2071 ru.port = child.port; 2072 ru.path = child.path; 2073 } 2074 2075 // 5.2 (7): Recombine (nothing to do here) 2076 return ru; 2077 } 2078 2079 // If the given URI's path is normal then return the URI; 2080 // o.w., return a new URI containing the normalized path. 2081 // 2082 private static URI normalize(URI u) { 2083 if (u.isOpaque() || (u.path == null) || (u.path.length() == 0)) 2084 return u; 2085 2086 String np = normalize(u.path); 2087 if (np == u.path) 2088 return u; 2089 2090 URI v = new URI(); 2091 v.scheme = u.scheme; 2092 v.fragment = u.fragment; 2093 v.authority = u.authority; 2094 v.userInfo = u.userInfo; 2095 v.host = u.host; 2096 v.port = u.port; 2097 v.path = np; 2098 v.query = u.query; 2099 return v; 2100 } 2101 2102 // If both URIs are hierarchical, their scheme and authority components are 2103 // identical, and the base path is a prefix of the child's path, then 2104 // return a relative URI that, when resolved against the base, yields the 2105 // child; otherwise, return the child. 2106 // 2107 private static URI relativize(URI base, URI child) { 2108 // check if child if opaque first so that NPE is thrown 2109 // if child is null. 2110 if (child.isOpaque() || base.isOpaque()) 2111 return child; 2112 if (!equalIgnoringCase(base.scheme, child.scheme) 2113 || !equal(base.authority, child.authority)) 2114 return child; 2115 2116 String bp = normalize(base.path); 2117 String cp = normalize(child.path); 2118 if (!bp.equals(cp)) { 2119 if (!bp.endsWith("/")) 2120 bp = bp + "/"; 2121 if (!cp.startsWith(bp)) 2122 return child; 2123 } 2124 2125 URI v = new URI(); 2126 v.path = cp.substring(bp.length()); 2127 v.query = child.query; 2128 v.fragment = child.fragment; 2129 return v; 2130 } 2131 2132 2133 2134 // -- Path normalization -- 2135 2136 // The following algorithm for path normalization avoids the creation of a 2137 // string object for each segment, as well as the use of a string buffer to 2138 // compute the final result, by using a single char array and editing it in 2139 // place. The array is first split into segments, replacing each slash 2140 // with '\0' and creating a segment-index array, each element of which is 2141 // the index of the first char in the corresponding segment. We then walk 2142 // through both arrays, removing ".", "..", and other segments as necessary 2143 // by setting their entries in the index array to -1. Finally, the two 2144 // arrays are used to rejoin the segments and compute the final result. 2145 // 2146 // This code is based upon src/solaris/native/java/io/canonicalize_md.c 2147 2148 2149 // Check the given path to see if it might need normalization. A path 2150 // might need normalization if it contains duplicate slashes, a "." 2151 // segment, or a ".." segment. Return -1 if no further normalization is 2152 // possible, otherwise return the number of segments found. 2153 // 2154 // This method takes a string argument rather than a char array so that 2155 // this test can be performed without invoking path.toCharArray(). 2156 // 2157 static private int needsNormalization(String path) { 2158 boolean normal = true; 2159 int ns = 0; // Number of segments 2160 int end = path.length() - 1; // Index of last char in path 2161 int p = 0; // Index of next char in path 2162 2163 // Skip initial slashes 2164 while (p <= end) { 2165 if (path.charAt(p) != '/') break; 2166 p++; 2167 } 2168 if (p > 1) normal = false; 2169 2170 // Scan segments 2171 while (p <= end) { 2172 2173 // Looking at "." or ".." ? 2174 if ((path.charAt(p) == '.') 2175 && ((p == end) 2176 || ((path.charAt(p + 1) == '/') 2177 || ((path.charAt(p + 1) == '.') 2178 && ((p + 1 == end) 2179 || (path.charAt(p + 2) == '/')))))) { 2180 normal = false; 2181 } 2182 ns++; 2183 2184 // Find beginning of next segment 2185 while (p <= end) { 2186 if (path.charAt(p++) != '/') 2187 continue; 2188 2189 // Skip redundant slashes 2190 while (p <= end) { 2191 if (path.charAt(p) != '/') break; 2192 normal = false; 2193 p++; 2194 } 2195 2196 break; 2197 } 2198 } 2199 2200 return normal ? -1 : ns; 2201 } 2202 2203 2204 // Split the given path into segments, replacing slashes with nulls and 2205 // filling in the given segment-index array. 2206 // 2207 // Preconditions: 2208 // segs.length == Number of segments in path 2209 // 2210 // Postconditions: 2211 // All slashes in path replaced by '\0' 2212 // segs[i] == Index of first char in segment i (0 <= i < segs.length) 2213 // 2214 static private void split(char[] path, int[] segs) { 2215 int end = path.length - 1; // Index of last char in path 2216 int p = 0; // Index of next char in path 2217 int i = 0; // Index of current segment 2218 2219 // Skip initial slashes 2220 while (p <= end) { 2221 if (path[p] != '/') break; 2222 path[p] = '\0'; 2223 p++; 2224 } 2225 2226 while (p <= end) { 2227 2228 // Note start of segment 2229 segs[i++] = p++; 2230 2231 // Find beginning of next segment 2232 while (p <= end) { 2233 if (path[p++] != '/') 2234 continue; 2235 path[p - 1] = '\0'; 2236 2237 // Skip redundant slashes 2238 while (p <= end) { 2239 if (path[p] != '/') break; 2240 path[p++] = '\0'; 2241 } 2242 break; 2243 } 2244 } 2245 2246 if (i != segs.length) 2247 throw new InternalError(); // ASSERT 2248 } 2249 2250 2251 // Join the segments in the given path according to the given segment-index 2252 // array, ignoring those segments whose index entries have been set to -1, 2253 // and inserting slashes as needed. Return the length of the resulting 2254 // path. 2255 // 2256 // Preconditions: 2257 // segs[i] == -1 implies segment i is to be ignored 2258 // path computed by split, as above, with '\0' having replaced '/' 2259 // 2260 // Postconditions: 2261 // path[0] .. path[return value] == Resulting path 2262 // 2263 static private int join(char[] path, int[] segs) { 2264 int ns = segs.length; // Number of segments 2265 int end = path.length - 1; // Index of last char in path 2266 int p = 0; // Index of next path char to write 2267 2268 if (path[p] == '\0') { 2269 // Restore initial slash for absolute paths 2270 path[p++] = '/'; 2271 } 2272 2273 for (int i = 0; i < ns; i++) { 2274 int q = segs[i]; // Current segment 2275 if (q == -1) 2276 // Ignore this segment 2277 continue; 2278 2279 if (p == q) { 2280 // We're already at this segment, so just skip to its end 2281 while ((p <= end) && (path[p] != '\0')) 2282 p++; 2283 if (p <= end) { 2284 // Preserve trailing slash 2285 path[p++] = '/'; 2286 } 2287 } else if (p < q) { 2288 // Copy q down to p 2289 while ((q <= end) && (path[q] != '\0')) 2290 path[p++] = path[q++]; 2291 if (q <= end) { 2292 // Preserve trailing slash 2293 path[p++] = '/'; 2294 } 2295 } else 2296 throw new InternalError(); // ASSERT false 2297 } 2298 2299 return p; 2300 } 2301 2302 2303 // Remove "." segments from the given path, and remove segment pairs 2304 // consisting of a non-".." segment followed by a ".." segment. 2305 // 2306 private static void removeDots(char[] path, int[] segs) { 2307 int ns = segs.length; 2308 int end = path.length - 1; 2309 2310 for (int i = 0; i < ns; i++) { 2311 int dots = 0; // Number of dots found (0, 1, or 2) 2312 2313 // Find next occurrence of "." or ".." 2314 do { 2315 int p = segs[i]; 2316 if (path[p] == '.') { 2317 if (p == end) { 2318 dots = 1; 2319 break; 2320 } else if (path[p + 1] == '\0') { 2321 dots = 1; 2322 break; 2323 } else if ((path[p + 1] == '.') 2324 && ((p + 1 == end) 2325 || (path[p + 2] == '\0'))) { 2326 dots = 2; 2327 break; 2328 } 2329 } 2330 i++; 2331 } while (i < ns); 2332 if ((i > ns) || (dots == 0)) 2333 break; 2334 2335 if (dots == 1) { 2336 // Remove this occurrence of "." 2337 segs[i] = -1; 2338 } else { 2339 // If there is a preceding non-".." segment, remove both that 2340 // segment and this occurrence of ".."; otherwise, leave this 2341 // ".." segment as-is. 2342 int j; 2343 for (j = i - 1; j >= 0; j--) { 2344 if (segs[j] != -1) break; 2345 } 2346 if (j >= 0) { 2347 int q = segs[j]; 2348 if (!((path[q] == '.') 2349 && (path[q + 1] == '.') 2350 && (path[q + 2] == '\0'))) { 2351 segs[i] = -1; 2352 segs[j] = -1; 2353 } 2354 } 2355 } 2356 } 2357 } 2358 2359 2360 // DEVIATION: If the normalized path is relative, and if the first 2361 // segment could be parsed as a scheme name, then prepend a "." segment 2362 // 2363 private static void maybeAddLeadingDot(char[] path, int[] segs) { 2364 2365 if (path[0] == '\0') 2366 // The path is absolute 2367 return; 2368 2369 int ns = segs.length; 2370 int f = 0; // Index of first segment 2371 while (f < ns) { 2372 if (segs[f] >= 0) 2373 break; 2374 f++; 2375 } 2376 if ((f >= ns) || (f == 0)) 2377 // The path is empty, or else the original first segment survived, 2378 // in which case we already know that no leading "." is needed 2379 return; 2380 2381 int p = segs[f]; 2382 while ((p < path.length) && (path[p] != ':') && (path[p] != '\0')) p++; 2383 if (p >= path.length || path[p] == '\0') 2384 // No colon in first segment, so no "." needed 2385 return; 2386 2387 // At this point we know that the first segment is unused, 2388 // hence we can insert a "." segment at that position 2389 path[0] = '.'; 2390 path[1] = '\0'; 2391 segs[0] = 0; 2392 } 2393 2394 2395 // Normalize the given path string. A normal path string has no empty 2396 // segments (i.e., occurrences of "//"), no segments equal to ".", and no 2397 // segments equal to ".." that are preceded by a segment not equal to "..". 2398 // In contrast to Unix-style pathname normalization, for URI paths we 2399 // always retain trailing slashes. 2400 // 2401 private static String normalize(String ps) { 2402 2403 // Does this path need normalization? 2404 int ns = needsNormalization(ps); // Number of segments 2405 if (ns < 0) 2406 // Nope -- just return it 2407 return ps; 2408 2409 char[] path = ps.toCharArray(); // Path in char-array form 2410 2411 // Split path into segments 2412 int[] segs = new int[ns]; // Segment-index array 2413 split(path, segs); 2414 2415 // Remove dots 2416 removeDots(path, segs); 2417 2418 // Prevent scheme-name confusion 2419 maybeAddLeadingDot(path, segs); 2420 2421 // Join the remaining segments and return the result 2422 String s = new String(path, 0, join(path, segs)); 2423 if (s.equals(ps)) { 2424 // string was already normalized 2425 return ps; 2426 } 2427 return s; 2428 } 2429 2430 2431 2432 // -- Character classes for parsing -- 2433 2434 // RFC2396 precisely specifies which characters in the US-ASCII charset are 2435 // permissible in the various components of a URI reference. We here 2436 // define a set of mask pairs to aid in enforcing these restrictions. Each 2437 // mask pair consists of two longs, a low mask and a high mask. Taken 2438 // together they represent a 128-bit mask, where bit i is set iff the 2439 // character with value i is permitted. 2440 // 2441 // This approach is more efficient than sequentially searching arrays of 2442 // permitted characters. It could be made still more efficient by 2443 // precompiling the mask information so that a character's presence in a 2444 // given mask could be determined by a single table lookup. 2445 2446 // Compute the low-order mask for the characters in the given string 2447 private static long lowMask(String chars) { 2448 int n = chars.length(); 2449 long m = 0; 2450 for (int i = 0; i < n; i++) { 2451 char c = chars.charAt(i); 2452 if (c < 64) 2453 m |= (1L << c); 2454 } 2455 return m; 2456 } 2457 2458 // Compute the high-order mask for the characters in the given string 2459 private static long highMask(String chars) { 2460 int n = chars.length(); 2461 long m = 0; 2462 for (int i = 0; i < n; i++) { 2463 char c = chars.charAt(i); 2464 if ((c >= 64) && (c < 128)) 2465 m |= (1L << (c - 64)); 2466 } 2467 return m; 2468 } 2469 2470 // Compute a low-order mask for the characters 2471 // between first and last, inclusive 2472 private static long lowMask(char first, char last) { 2473 long m = 0; 2474 int f = Math.max(Math.min(first, 63), 0); 2475 int l = Math.max(Math.min(last, 63), 0); 2476 for (int i = f; i <= l; i++) 2477 m |= 1L << i; 2478 return m; 2479 } 2480 2481 // Compute a high-order mask for the characters 2482 // between first and last, inclusive 2483 private static long highMask(char first, char last) { 2484 long m = 0; 2485 int f = Math.max(Math.min(first, 127), 64) - 64; 2486 int l = Math.max(Math.min(last, 127), 64) - 64; 2487 for (int i = f; i <= l; i++) 2488 m |= 1L << i; 2489 return m; 2490 } 2491 2492 // Tell whether the given character is permitted by the given mask pair 2493 private static boolean match(char c, long lowMask, long highMask) { 2494 if (c == 0) // 0 doesn't have a slot in the mask. So, it never matches. 2495 return false; 2496 if (c < 64) 2497 return ((1L << c) & lowMask) != 0; 2498 if (c < 128) 2499 return ((1L << (c - 64)) & highMask) != 0; 2500 return false; 2501 } 2502 2503 // Character-class masks, in reverse order from RFC2396 because 2504 // initializers for static fields cannot make forward references. 2505 2506 // digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | 2507 // "8" | "9" 2508 private static final long L_DIGIT = lowMask('0', '9'); 2509 private static final long H_DIGIT = 0L; 2510 2511 // upalpha = "A" | "B" | "C" | "D" | "E" | "F" | "G" | "H" | "I" | 2512 // "J" | "K" | "L" | "M" | "N" | "O" | "P" | "Q" | "R" | 2513 // "S" | "T" | "U" | "V" | "W" | "X" | "Y" | "Z" 2514 private static final long L_UPALPHA = 0L; 2515 private static final long H_UPALPHA = highMask('A', 'Z'); 2516 2517 // lowalpha = "a" | "b" | "c" | "d" | "e" | "f" | "g" | "h" | "i" | 2518 // "j" | "k" | "l" | "m" | "n" | "o" | "p" | "q" | "r" | 2519 // "s" | "t" | "u" | "v" | "w" | "x" | "y" | "z" 2520 private static final long L_LOWALPHA = 0L; 2521 private static final long H_LOWALPHA = highMask('a', 'z'); 2522 2523 // alpha = lowalpha | upalpha 2524 private static final long L_ALPHA = L_LOWALPHA | L_UPALPHA; 2525 private static final long H_ALPHA = H_LOWALPHA | H_UPALPHA; 2526 2527 // alphanum = alpha | digit 2528 private static final long L_ALPHANUM = L_DIGIT | L_ALPHA; 2529 private static final long H_ALPHANUM = H_DIGIT | H_ALPHA; 2530 2531 // hex = digit | "A" | "B" | "C" | "D" | "E" | "F" | 2532 // "a" | "b" | "c" | "d" | "e" | "f" 2533 private static final long L_HEX = L_DIGIT; 2534 private static final long H_HEX = highMask('A', 'F') | highMask('a', 'f'); 2535 2536 // mark = "-" | "_" | "." | "!" | "~" | "*" | "'" | 2537 // "(" | ")" 2538 private static final long L_MARK = lowMask("-_.!~*'()"); 2539 private static final long H_MARK = highMask("-_.!~*'()"); 2540 2541 // unreserved = alphanum | mark 2542 private static final long L_UNRESERVED = L_ALPHANUM | L_MARK; 2543 private static final long H_UNRESERVED = H_ALPHANUM | H_MARK; 2544 2545 // reserved = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" | 2546 // "$" | "," | "[" | "]" 2547 // Added per RFC2732: "[", "]" 2548 private static final long L_RESERVED = lowMask(";/?:@&=+$,[]"); 2549 private static final long H_RESERVED = highMask(";/?:@&=+$,[]"); 2550 2551 // The zero'th bit is used to indicate that escape pairs and non-US-ASCII 2552 // characters are allowed; this is handled by the scanEscape method below. 2553 private static final long L_ESCAPED = 1L; 2554 private static final long H_ESCAPED = 0L; 2555 2556 // uric = reserved | unreserved | escaped 2557 private static final long L_URIC = L_RESERVED | L_UNRESERVED | L_ESCAPED; 2558 private static final long H_URIC = H_RESERVED | H_UNRESERVED | H_ESCAPED; 2559 2560 // pchar = unreserved | escaped | 2561 // ":" | "@" | "&" | "=" | "+" | "$" | "," 2562 private static final long L_PCHAR 2563 = L_UNRESERVED | L_ESCAPED | lowMask(":@&=+$,"); 2564 private static final long H_PCHAR 2565 = H_UNRESERVED | H_ESCAPED | highMask(":@&=+$,"); 2566 2567 // All valid path characters 2568 private static final long L_PATH = L_PCHAR | lowMask(";/"); 2569 private static final long H_PATH = H_PCHAR | highMask(";/"); 2570 2571 // Dash, for use in domainlabel and toplabel 2572 private static final long L_DASH = lowMask("-"); 2573 private static final long H_DASH = highMask("-"); 2574 2575 // Dot, for use in hostnames 2576 private static final long L_DOT = lowMask("."); 2577 private static final long H_DOT = highMask("."); 2578 2579 // userinfo = *( unreserved | escaped | 2580 // ";" | ":" | "&" | "=" | "+" | "$" | "," ) 2581 private static final long L_USERINFO 2582 = L_UNRESERVED | L_ESCAPED | lowMask(";:&=+$,"); 2583 private static final long H_USERINFO 2584 = H_UNRESERVED | H_ESCAPED | highMask(";:&=+$,"); 2585 2586 // reg_name = 1*( unreserved | escaped | "$" | "," | 2587 // ";" | ":" | "@" | "&" | "=" | "+" ) 2588 private static final long L_REG_NAME 2589 = L_UNRESERVED | L_ESCAPED | lowMask("$,;:@&=+"); 2590 private static final long H_REG_NAME 2591 = H_UNRESERVED | H_ESCAPED | highMask("$,;:@&=+"); 2592 2593 // All valid characters for server-based authorities 2594 private static final long L_SERVER 2595 = L_USERINFO | L_ALPHANUM | L_DASH | lowMask(".:@[]"); 2596 private static final long H_SERVER 2597 = H_USERINFO | H_ALPHANUM | H_DASH | highMask(".:@[]"); 2598 2599 // Special case of server authority that represents an IPv6 address 2600 // In this case, a % does not signify an escape sequence 2601 private static final long L_SERVER_PERCENT 2602 = L_SERVER | lowMask("%"); 2603 private static final long H_SERVER_PERCENT 2604 = H_SERVER | highMask("%"); 2605 private static final long L_LEFT_BRACKET = lowMask("["); 2606 private static final long H_LEFT_BRACKET = highMask("["); 2607 2608 // scheme = alpha *( alpha | digit | "+" | "-" | "." ) 2609 private static final long L_SCHEME = L_ALPHA | L_DIGIT | lowMask("+-."); 2610 private static final long H_SCHEME = H_ALPHA | H_DIGIT | highMask("+-."); 2611 2612 // uric_no_slash = unreserved | escaped | ";" | "?" | ":" | "@" | 2613 // "&" | "=" | "+" | "$" | "," 2614 private static final long L_URIC_NO_SLASH 2615 = L_UNRESERVED | L_ESCAPED | lowMask(";?:@&=+$,"); 2616 private static final long H_URIC_NO_SLASH 2617 = H_UNRESERVED | H_ESCAPED | highMask(";?:@&=+$,"); 2618 2619 2620 // -- Escaping and encoding -- 2621 2622 private final static char[] hexDigits = { 2623 '0', '1', '2', '3', '4', '5', '6', '7', 2624 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' 2625 }; 2626 2627 private static void appendEscape(StringBuffer sb, byte b) { 2628 sb.append('%'); 2629 sb.append(hexDigits[(b >> 4) & 0x0f]); 2630 sb.append(hexDigits[(b >> 0) & 0x0f]); 2631 } 2632 2633 private static void appendEncoded(StringBuffer sb, char c) { 2634 ByteBuffer bb = null; 2635 try { 2636 bb = ThreadLocalCoders.encoderFor("UTF-8") 2637 .encode(CharBuffer.wrap("" + c)); 2638 } catch (CharacterCodingException x) { 2639 assert false; 2640 } 2641 while (bb.hasRemaining()) { 2642 int b = bb.get() & 0xff; 2643 if (b >= 0x80) 2644 appendEscape(sb, (byte)b); 2645 else 2646 sb.append((char)b); 2647 } 2648 } 2649 2650 // Quote any characters in s that are not permitted 2651 // by the given mask pair 2652 // 2653 private static String quote(String s, long lowMask, long highMask) { 2654 int n = s.length(); 2655 StringBuffer sb = null; 2656 boolean allowNonASCII = ((lowMask & L_ESCAPED) != 0); 2657 for (int i = 0; i < s.length(); i++) { 2658 char c = s.charAt(i); 2659 if (c < '\u0080') { 2660 if (!match(c, lowMask, highMask)) { 2661 if (sb == null) { 2662 sb = new StringBuffer(); 2663 sb.append(s.substring(0, i)); 2664 } 2665 appendEscape(sb, (byte)c); 2666 } else { 2667 if (sb != null) 2668 sb.append(c); 2669 } 2670 } else if (allowNonASCII 2671 && (Character.isSpaceChar(c) 2672 || Character.isISOControl(c))) { 2673 if (sb == null) { 2674 sb = new StringBuffer(); 2675 sb.append(s.substring(0, i)); 2676 } 2677 appendEncoded(sb, c); 2678 } else { 2679 if (sb != null) 2680 sb.append(c); 2681 } 2682 } 2683 return (sb == null) ? s : sb.toString(); 2684 } 2685 2686 // Encodes all characters >= \u0080 into escaped, normalized UTF-8 octets, 2687 // assuming that s is otherwise legal 2688 // 2689 private static String encode(String s) { 2690 int n = s.length(); 2691 if (n == 0) 2692 return s; 2693 2694 // First check whether we actually need to encode 2695 for (int i = 0;;) { 2696 if (s.charAt(i) >= '\u0080') 2697 break; 2698 if (++i >= n) 2699 return s; 2700 } 2701 2702 String ns = Normalizer.normalize(s, Normalizer.Form.NFC); 2703 ByteBuffer bb = null; 2704 try { 2705 bb = ThreadLocalCoders.encoderFor("UTF-8") 2706 .encode(CharBuffer.wrap(ns)); 2707 } catch (CharacterCodingException x) { 2708 assert false; 2709 } 2710 2711 StringBuffer sb = new StringBuffer(); 2712 while (bb.hasRemaining()) { 2713 int b = bb.get() & 0xff; 2714 if (b >= 0x80) 2715 appendEscape(sb, (byte)b); 2716 else 2717 sb.append((char)b); 2718 } 2719 return sb.toString(); 2720 } 2721 2722 private static int decode(char c) { 2723 if ((c >= '0') && (c <= '9')) 2724 return c - '0'; 2725 if ((c >= 'a') && (c <= 'f')) 2726 return c - 'a' + 10; 2727 if ((c >= 'A') && (c <= 'F')) 2728 return c - 'A' + 10; 2729 assert false; 2730 return -1; 2731 } 2732 2733 private static byte decode(char c1, char c2) { 2734 return (byte)( ((decode(c1) & 0xf) << 4) 2735 | ((decode(c2) & 0xf) << 0)); 2736 } 2737 2738 // Evaluates all escapes in s, applying UTF-8 decoding if needed. Assumes 2739 // that escapes are well-formed syntactically, i.e., of the form %XX. If a 2740 // sequence of escaped octets is not valid UTF-8 then the erroneous octets 2741 // are replaced with '\uFFFD'. 2742 // Exception: any "%" found between "[]" is left alone. It is an IPv6 literal 2743 // with a scope_id 2744 // 2745 private static String decode(String s) { 2746 if (s == null) 2747 return s; 2748 int n = s.length(); 2749 if (n == 0) 2750 return s; 2751 if (s.indexOf('%') < 0) 2752 return s; 2753 2754 StringBuffer sb = new StringBuffer(n); 2755 ByteBuffer bb = ByteBuffer.allocate(n); 2756 CharBuffer cb = CharBuffer.allocate(n); 2757 CharsetDecoder dec = ThreadLocalCoders.decoderFor("UTF-8") 2758 .onMalformedInput(CodingErrorAction.REPLACE) 2759 .onUnmappableCharacter(CodingErrorAction.REPLACE); 2760 2761 // This is not horribly efficient, but it will do for now 2762 char c = s.charAt(0); 2763 boolean betweenBrackets = false; 2764 2765 for (int i = 0; i < n;) { 2766 assert c == s.charAt(i); // Loop invariant 2767 if (c == '[') { 2768 betweenBrackets = true; 2769 } else if (betweenBrackets && c == ']') { 2770 betweenBrackets = false; 2771 } 2772 if (c != '%' || betweenBrackets) { 2773 sb.append(c); 2774 if (++i >= n) 2775 break; 2776 c = s.charAt(i); 2777 continue; 2778 } 2779 bb.clear(); 2780 int ui = i; 2781 for (;;) { 2782 assert (n - i >= 2); 2783 bb.put(decode(s.charAt(++i), s.charAt(++i))); 2784 if (++i >= n) 2785 break; 2786 c = s.charAt(i); 2787 if (c != '%') 2788 break; 2789 } 2790 bb.flip(); 2791 cb.clear(); 2792 dec.reset(); 2793 CoderResult cr = dec.decode(bb, cb, true); 2794 assert cr.isUnderflow(); 2795 cr = dec.flush(cb); 2796 assert cr.isUnderflow(); 2797 sb.append(cb.flip().toString()); 2798 } 2799 2800 return sb.toString(); 2801 } 2802 2803 2804 // -- Parsing -- 2805 2806 // For convenience we wrap the input URI string in a new instance of the 2807 // following internal class. This saves always having to pass the input 2808 // string as an argument to each internal scan/parse method. 2809 2810 private class Parser { 2811 2812 private String input; // URI input string 2813 private boolean requireServerAuthority = false; 2814 2815 Parser(String s) { 2816 input = s; 2817 string = s; 2818 } 2819 2820 // -- Methods for throwing URISyntaxException in various ways -- 2821 2822 private void fail(String reason) throws URISyntaxException { 2823 throw new URISyntaxException(input, reason); 2824 } 2825 2826 private void fail(String reason, int p) throws URISyntaxException { 2827 throw new URISyntaxException(input, reason, p); 2828 } 2829 2830 private void failExpecting(String expected, int p) 2831 throws URISyntaxException 2832 { 2833 fail("Expected " + expected, p); 2834 } 2835 2836 private void failExpecting(String expected, String prior, int p) 2837 throws URISyntaxException 2838 { 2839 fail("Expected " + expected + " following " + prior, p); 2840 } 2841 2842 2843 // -- Simple access to the input string -- 2844 2845 // Return a substring of the input string 2846 // 2847 private String substring(int start, int end) { 2848 return input.substring(start, end); 2849 } 2850 2851 // Return the char at position p, 2852 // assuming that p < input.length() 2853 // 2854 private char charAt(int p) { 2855 return input.charAt(p); 2856 } 2857 2858 // Tells whether start < end and, if so, whether charAt(start) == c 2859 // 2860 private boolean at(int start, int end, char c) { 2861 return (start < end) && (charAt(start) == c); 2862 } 2863 2864 // Tells whether start + s.length() < end and, if so, 2865 // whether the chars at the start position match s exactly 2866 // 2867 private boolean at(int start, int end, String s) { 2868 int p = start; 2869 int sn = s.length(); 2870 if (sn > end - p) 2871 return false; 2872 int i = 0; 2873 while (i < sn) { 2874 if (charAt(p++) != s.charAt(i)) { 2875 break; 2876 } 2877 i++; 2878 } 2879 return (i == sn); 2880 } 2881 2882 2883 // -- Scanning -- 2884 2885 // The various scan and parse methods that follow use a uniform 2886 // convention of taking the current start position and end index as 2887 // their first two arguments. The start is inclusive while the end is 2888 // exclusive, just as in the String class, i.e., a start/end pair 2889 // denotes the left-open interval [start, end) of the input string. 2890 // 2891 // These methods never proceed past the end position. They may return 2892 // -1 to indicate outright failure, but more often they simply return 2893 // the position of the first char after the last char scanned. Thus 2894 // a typical idiom is 2895 // 2896 // int p = start; 2897 // int q = scan(p, end, ...); 2898 // if (q > p) 2899 // // We scanned something 2900 // ...; 2901 // else if (q == p) 2902 // // We scanned nothing 2903 // ...; 2904 // else if (q == -1) 2905 // // Something went wrong 2906 // ...; 2907 2908 2909 // Scan a specific char: If the char at the given start position is 2910 // equal to c, return the index of the next char; otherwise, return the 2911 // start position. 2912 // 2913 private int scan(int start, int end, char c) { 2914 if ((start < end) && (charAt(start) == c)) 2915 return start + 1; 2916 return start; 2917 } 2918 2919 // Scan forward from the given start position. Stop at the first char 2920 // in the err string (in which case -1 is returned), or the first char 2921 // in the stop string (in which case the index of the preceding char is 2922 // returned), or the end of the input string (in which case the length 2923 // of the input string is returned). May return the start position if 2924 // nothing matches. 2925 // 2926 private int scan(int start, int end, String err, String stop) { 2927 int p = start; 2928 while (p < end) { 2929 char c = charAt(p); 2930 if (err.indexOf(c) >= 0) 2931 return -1; 2932 if (stop.indexOf(c) >= 0) 2933 break; 2934 p++; 2935 } 2936 return p; 2937 } 2938 2939 // Scan a potential escape sequence, starting at the given position, 2940 // with the given first char (i.e., charAt(start) == c). 2941 // 2942 // This method assumes that if escapes are allowed then visible 2943 // non-US-ASCII chars are also allowed. 2944 // 2945 private int scanEscape(int start, int n, char first) 2946 throws URISyntaxException 2947 { 2948 int p = start; 2949 char c = first; 2950 if (c == '%') { 2951 // Process escape pair 2952 if ((p + 3 <= n) 2953 && match(charAt(p + 1), L_HEX, H_HEX) 2954 && match(charAt(p + 2), L_HEX, H_HEX)) { 2955 return p + 3; 2956 } 2957 fail("Malformed escape pair", p); 2958 } else if ((c > 128) 2959 && !Character.isSpaceChar(c) 2960 && !Character.isISOControl(c)) { 2961 // Allow unescaped but visible non-US-ASCII chars 2962 return p + 1; 2963 } 2964 return p; 2965 } 2966 2967 // Scan chars that match the given mask pair 2968 // 2969 private int scan(int start, int n, long lowMask, long highMask) 2970 throws URISyntaxException 2971 { 2972 int p = start; 2973 while (p < n) { 2974 char c = charAt(p); 2975 if (match(c, lowMask, highMask)) { 2976 p++; 2977 continue; 2978 } 2979 if ((lowMask & L_ESCAPED) != 0) { 2980 int q = scanEscape(p, n, c); 2981 if (q > p) { 2982 p = q; 2983 continue; 2984 } 2985 } 2986 break; 2987 } 2988 return p; 2989 } 2990 2991 // Check that each of the chars in [start, end) matches the given mask 2992 // 2993 private void checkChars(int start, int end, 2994 long lowMask, long highMask, 2995 String what) 2996 throws URISyntaxException 2997 { 2998 int p = scan(start, end, lowMask, highMask); 2999 if (p < end) 3000 fail("Illegal character in " + what, p); 3001 } 3002 3003 // Check that the char at position p matches the given mask 3004 // 3005 private void checkChar(int p, 3006 long lowMask, long highMask, 3007 String what) 3008 throws URISyntaxException 3009 { 3010 checkChars(p, p + 1, lowMask, highMask, what); 3011 } 3012 3013 3014 // -- Parsing -- 3015 3016 // [<scheme>:]<scheme-specific-part>[#<fragment>] 3017 // 3018 void parse(boolean rsa) throws URISyntaxException { 3019 requireServerAuthority = rsa; 3020 int ssp; // Start of scheme-specific part 3021 int n = input.length(); 3022 int p = scan(0, n, "/?#", ":"); 3023 if ((p >= 0) && at(p, n, ':')) { 3024 if (p == 0) 3025 failExpecting("scheme name", 0); 3026 checkChar(0, L_ALPHA, H_ALPHA, "scheme name"); 3027 checkChars(1, p, L_SCHEME, H_SCHEME, "scheme name"); 3028 scheme = substring(0, p); 3029 p++; // Skip ':' 3030 ssp = p; 3031 if (at(p, n, '/')) { 3032 p = parseHierarchical(p, n); 3033 } else { 3034 int q = scan(p, n, "", "#"); 3035 if (q <= p) 3036 failExpecting("scheme-specific part", p); 3037 checkChars(p, q, L_URIC, H_URIC, "opaque part"); 3038 p = q; 3039 } 3040 } else { 3041 ssp = 0; 3042 p = parseHierarchical(0, n); 3043 } 3044 schemeSpecificPart = substring(ssp, p); 3045 if (at(p, n, '#')) { 3046 checkChars(p + 1, n, L_URIC, H_URIC, "fragment"); 3047 fragment = substring(p + 1, n); 3048 p = n; 3049 } 3050 if (p < n) 3051 fail("end of URI", p); 3052 } 3053 3054 // [//authority]<path>[?<query>] 3055 // 3056 // DEVIATION from RFC2396: We allow an empty authority component as 3057 // long as it's followed by a non-empty path, query component, or 3058 // fragment component. This is so that URIs such as "file:///foo/bar" 3059 // will parse. This seems to be the intent of RFC2396, though the 3060 // grammar does not permit it. If the authority is empty then the 3061 // userInfo, host, and port components are undefined. 3062 // 3063 // DEVIATION from RFC2396: We allow empty relative paths. This seems 3064 // to be the intent of RFC2396, but the grammar does not permit it. 3065 // The primary consequence of this deviation is that "#f" parses as a 3066 // relative URI with an empty path. 3067 // 3068 private int parseHierarchical(int start, int n) 3069 throws URISyntaxException 3070 { 3071 int p = start; 3072 if (at(p, n, '/') && at(p + 1, n, '/')) { 3073 p += 2; 3074 int q = scan(p, n, "", "/?#"); 3075 if (q > p) { 3076 p = parseAuthority(p, q); 3077 } else if (q < n) { 3078 // DEVIATION: Allow empty authority prior to non-empty 3079 // path, query component or fragment identifier 3080 } else 3081 failExpecting("authority", p); 3082 } 3083 int q = scan(p, n, "", "?#"); // DEVIATION: May be empty 3084 checkChars(p, q, L_PATH, H_PATH, "path"); 3085 path = substring(p, q); 3086 p = q; 3087 if (at(p, n, '?')) { 3088 p++; 3089 q = scan(p, n, "", "#"); 3090 checkChars(p, q, L_URIC, H_URIC, "query"); 3091 query = substring(p, q); 3092 p = q; 3093 } 3094 return p; 3095 } 3096 3097 // authority = server | reg_name 3098 // 3099 // Ambiguity: An authority that is a registry name rather than a server 3100 // might have a prefix that parses as a server. We use the fact that 3101 // the authority component is always followed by '/' or the end of the 3102 // input string to resolve this: If the complete authority did not 3103 // parse as a server then we try to parse it as a registry name. 3104 // 3105 private int parseAuthority(int start, int n) 3106 throws URISyntaxException 3107 { 3108 int p = start; 3109 int q = p; 3110 URISyntaxException ex = null; 3111 3112 boolean serverChars; 3113 boolean regChars; 3114 3115 if (scan(p, n, "", "]") > p) { 3116 // contains a literal IPv6 address, therefore % is allowed 3117 serverChars = (scan(p, n, L_SERVER_PERCENT, H_SERVER_PERCENT) == n); 3118 } else { 3119 serverChars = (scan(p, n, L_SERVER, H_SERVER) == n); 3120 } 3121 regChars = (scan(p, n, L_REG_NAME, H_REG_NAME) == n); 3122 3123 if (regChars && !serverChars) { 3124 // Must be a registry-based authority 3125 authority = substring(p, n); 3126 return n; 3127 } 3128 3129 if (serverChars) { 3130 // Might be (probably is) a server-based authority, so attempt 3131 // to parse it as such. If the attempt fails, try to treat it 3132 // as a registry-based authority. 3133 try { 3134 q = parseServer(p, n); 3135 if (q < n) 3136 failExpecting("end of authority", q); 3137 authority = substring(p, n); 3138 } catch (URISyntaxException x) { 3139 // Undo results of failed parse 3140 userInfo = null; 3141 host = null; 3142 port = -1; 3143 if (requireServerAuthority) { 3144 // If we're insisting upon a server-based authority, 3145 // then just re-throw the exception 3146 throw x; 3147 } else { 3148 // Save the exception in case it doesn't parse as a 3149 // registry either 3150 ex = x; 3151 q = p; 3152 } 3153 } 3154 } 3155 3156 if (q < n) { 3157 if (regChars) { 3158 // Registry-based authority 3159 authority = substring(p, n); 3160 } else if (ex != null) { 3161 // Re-throw exception; it was probably due to 3162 // a malformed IPv6 address 3163 throw ex; 3164 } else { 3165 fail("Illegal character in authority", q); 3166 } 3167 } 3168 3169 return n; 3170 } 3171 3172 3173 // [<userinfo>@]<host>[:<port>] 3174 // 3175 private int parseServer(int start, int n) 3176 throws URISyntaxException 3177 { 3178 int p = start; 3179 int q; 3180 3181 // userinfo 3182 q = scan(p, n, "/?#", "@"); 3183 if ((q >= p) && at(q, n, '@')) { 3184 checkChars(p, q, L_USERINFO, H_USERINFO, "user info"); 3185 userInfo = substring(p, q); 3186 p = q + 1; // Skip '@' 3187 } 3188 3189 // hostname, IPv4 address, or IPv6 address 3190 if (at(p, n, '[')) { 3191 // DEVIATION from RFC2396: Support IPv6 addresses, per RFC2732 3192 p++; 3193 q = scan(p, n, "/?#", "]"); 3194 if ((q > p) && at(q, n, ']')) { 3195 // look for a "%" scope id 3196 int r = scan (p, q, "", "%"); 3197 if (r > p) { 3198 parseIPv6Reference(p, r); 3199 if (r+1 == q) { 3200 fail ("scope id expected"); 3201 } 3202 checkChars (r+1, q, L_ALPHANUM, H_ALPHANUM, 3203 "scope id"); 3204 } else { 3205 parseIPv6Reference(p, q); 3206 } 3207 host = substring(p-1, q+1); 3208 p = q + 1; 3209 } else { 3210 failExpecting("closing bracket for IPv6 address", q); 3211 } 3212 } else { 3213 q = parseIPv4Address(p, n); 3214 if (q <= p) 3215 q = parseHostname(p, n); 3216 p = q; 3217 } 3218 3219 // port 3220 if (at(p, n, ':')) { 3221 p++; 3222 q = scan(p, n, "", "/"); 3223 if (q > p) { 3224 checkChars(p, q, L_DIGIT, H_DIGIT, "port number"); 3225 try { 3226 port = Integer.parseInt(substring(p, q)); 3227 } catch (NumberFormatException x) { 3228 fail("Malformed port number", p); 3229 } 3230 p = q; 3231 } 3232 } 3233 if (p < n) 3234 failExpecting("port number", p); 3235 3236 return p; 3237 } 3238 3239 // Scan a string of decimal digits whose value fits in a byte 3240 // 3241 private int scanByte(int start, int n) 3242 throws URISyntaxException 3243 { 3244 int p = start; 3245 int q = scan(p, n, L_DIGIT, H_DIGIT); 3246 if (q <= p) return q; 3247 if (Integer.parseInt(substring(p, q)) > 255) return p; 3248 return q; 3249 } 3250 3251 // Scan an IPv4 address. 3252 // 3253 // If the strict argument is true then we require that the given 3254 // interval contain nothing besides an IPv4 address; if it is false 3255 // then we only require that it start with an IPv4 address. 3256 // 3257 // If the interval does not contain or start with (depending upon the 3258 // strict argument) a legal IPv4 address characters then we return -1 3259 // immediately; otherwise we insist that these characters parse as a 3260 // legal IPv4 address and throw an exception on failure. 3261 // 3262 // We assume that any string of decimal digits and dots must be an IPv4 3263 // address. It won't parse as a hostname anyway, so making that 3264 // assumption here allows more meaningful exceptions to be thrown. 3265 // 3266 private int scanIPv4Address(int start, int n, boolean strict) 3267 throws URISyntaxException 3268 { 3269 int p = start; 3270 int q; 3271 int m = scan(p, n, L_DIGIT | L_DOT, H_DIGIT | H_DOT); 3272 if ((m <= p) || (strict && (m != n))) 3273 return -1; 3274 for (;;) { 3275 // Per RFC2732: At most three digits per byte 3276 // Further constraint: Each element fits in a byte 3277 if ((q = scanByte(p, m)) <= p) break; p = q; 3278 if ((q = scan(p, m, '.')) <= p) break; p = q; 3279 if ((q = scanByte(p, m)) <= p) break; p = q; 3280 if ((q = scan(p, m, '.')) <= p) break; p = q; 3281 if ((q = scanByte(p, m)) <= p) break; p = q; 3282 if ((q = scan(p, m, '.')) <= p) break; p = q; 3283 if ((q = scanByte(p, m)) <= p) break; p = q; 3284 if (q < m) break; 3285 return q; 3286 } 3287 fail("Malformed IPv4 address", q); 3288 return -1; 3289 } 3290 3291 // Take an IPv4 address: Throw an exception if the given interval 3292 // contains anything except an IPv4 address 3293 // 3294 private int takeIPv4Address(int start, int n, String expected) 3295 throws URISyntaxException 3296 { 3297 int p = scanIPv4Address(start, n, true); 3298 if (p <= start) 3299 failExpecting(expected, start); 3300 return p; 3301 } 3302 3303 // Attempt to parse an IPv4 address, returning -1 on failure but 3304 // allowing the given interval to contain [:<characters>] after 3305 // the IPv4 address. 3306 // 3307 private int parseIPv4Address(int start, int n) { 3308 int p; 3309 3310 try { 3311 p = scanIPv4Address(start, n, false); 3312 } catch (URISyntaxException x) { 3313 return -1; 3314 } catch (NumberFormatException nfe) { 3315 return -1; 3316 } 3317 3318 if (p > start && p < n) { 3319 // IPv4 address is followed by something - check that 3320 // it's a ":" as this is the only valid character to 3321 // follow an address. 3322 if (charAt(p) != ':') { 3323 p = -1; 3324 } 3325 } 3326 3327 if (p > start) 3328 host = substring(start, p); 3329 3330 return p; 3331 } 3332 3333 // hostname = domainlabel [ "." ] | 1*( domainlabel "." ) toplabel [ "." ] 3334 // domainlabel = alphanum | alphanum *( alphanum | "-" ) alphanum 3335 // toplabel = alpha | alpha *( alphanum | "-" ) alphanum 3336 // 3337 private int parseHostname(int start, int n) 3338 throws URISyntaxException 3339 { 3340 int p = start; 3341 int q; 3342 int l = -1; // Start of last parsed label 3343 3344 do { 3345 // domainlabel = alphanum [ *( alphanum | "-" ) alphanum ] 3346 q = scan(p, n, L_ALPHANUM, H_ALPHANUM); 3347 if (q <= p) 3348 break; 3349 l = p; 3350 if (q > p) { 3351 p = q; 3352 q = scan(p, n, L_ALPHANUM | L_DASH, H_ALPHANUM | H_DASH); 3353 if (q > p) { 3354 if (charAt(q - 1) == '-') 3355 fail("Illegal character in hostname", q - 1); 3356 p = q; 3357 } 3358 } 3359 q = scan(p, n, '.'); 3360 if (q <= p) 3361 break; 3362 p = q; 3363 } while (p < n); 3364 3365 if ((p < n) && !at(p, n, ':')) 3366 fail("Illegal character in hostname", p); 3367 3368 if (l < 0) 3369 failExpecting("hostname", start); 3370 3371 // for a fully qualified hostname check that the rightmost 3372 // label starts with an alpha character. 3373 if (l > start && !match(charAt(l), L_ALPHA, H_ALPHA)) { 3374 fail("Illegal character in hostname", l); 3375 } 3376 3377 host = substring(start, p); 3378 return p; 3379 } 3380 3381 3382 // IPv6 address parsing, from RFC2373: IPv6 Addressing Architecture 3383 // 3384 // Bug: The grammar in RFC2373 Appendix B does not allow addresses of 3385 // the form ::12.34.56.78, which are clearly shown in the examples 3386 // earlier in the document. Here is the original grammar: 3387 // 3388 // IPv6address = hexpart [ ":" IPv4address ] 3389 // hexpart = hexseq | hexseq "::" [ hexseq ] | "::" [ hexseq ] 3390 // hexseq = hex4 *( ":" hex4) 3391 // hex4 = 1*4HEXDIG 3392 // 3393 // We therefore use the following revised grammar: 3394 // 3395 // IPv6address = hexseq [ ":" IPv4address ] 3396 // | hexseq [ "::" [ hexpost ] ] 3397 // | "::" [ hexpost ] 3398 // hexpost = hexseq | hexseq ":" IPv4address | IPv4address 3399 // hexseq = hex4 *( ":" hex4) 3400 // hex4 = 1*4HEXDIG 3401 // 3402 // This covers all and only the following cases: 3403 // 3404 // hexseq 3405 // hexseq : IPv4address 3406 // hexseq :: 3407 // hexseq :: hexseq 3408 // hexseq :: hexseq : IPv4address 3409 // hexseq :: IPv4address 3410 // :: hexseq 3411 // :: hexseq : IPv4address 3412 // :: IPv4address 3413 // :: 3414 // 3415 // Additionally we constrain the IPv6 address as follows :- 3416 // 3417 // i. IPv6 addresses without compressed zeros should contain 3418 // exactly 16 bytes. 3419 // 3420 // ii. IPv6 addresses with compressed zeros should contain 3421 // less than 16 bytes. 3422 3423 private int ipv6byteCount = 0; 3424 3425 private int parseIPv6Reference(int start, int n) 3426 throws URISyntaxException 3427 { 3428 int p = start; 3429 int q; 3430 boolean compressedZeros = false; 3431 3432 q = scanHexSeq(p, n); 3433 3434 if (q > p) { 3435 p = q; 3436 if (at(p, n, "::")) { 3437 compressedZeros = true; 3438 p = scanHexPost(p + 2, n); 3439 } else if (at(p, n, ':')) { 3440 p = takeIPv4Address(p + 1, n, "IPv4 address"); 3441 ipv6byteCount += 4; 3442 } 3443 } else if (at(p, n, "::")) { 3444 compressedZeros = true; 3445 p = scanHexPost(p + 2, n); 3446 } 3447 if (p < n) 3448 fail("Malformed IPv6 address", start); 3449 if (ipv6byteCount > 16) 3450 fail("IPv6 address too long", start); 3451 if (!compressedZeros && ipv6byteCount < 16) 3452 fail("IPv6 address too short", start); 3453 if (compressedZeros && ipv6byteCount == 16) 3454 fail("Malformed IPv6 address", start); 3455 3456 return p; 3457 } 3458 3459 private int scanHexPost(int start, int n) 3460 throws URISyntaxException 3461 { 3462 int p = start; 3463 int q; 3464 3465 if (p == n) 3466 return p; 3467 3468 q = scanHexSeq(p, n); 3469 if (q > p) { 3470 p = q; 3471 if (at(p, n, ':')) { 3472 p++; 3473 p = takeIPv4Address(p, n, "hex digits or IPv4 address"); 3474 ipv6byteCount += 4; 3475 } 3476 } else { 3477 p = takeIPv4Address(p, n, "hex digits or IPv4 address"); 3478 ipv6byteCount += 4; 3479 } 3480 return p; 3481 } 3482 3483 // Scan a hex sequence; return -1 if one could not be scanned 3484 // 3485 private int scanHexSeq(int start, int n) 3486 throws URISyntaxException 3487 { 3488 int p = start; 3489 int q; 3490 3491 q = scan(p, n, L_HEX, H_HEX); 3492 if (q <= p) 3493 return -1; 3494 if (at(q, n, '.')) // Beginning of IPv4 address 3495 return -1; 3496 if (q > p + 4) 3497 fail("IPv6 hexadecimal digit sequence too long", p); 3498 ipv6byteCount += 2; 3499 p = q; 3500 while (p < n) { 3501 if (!at(p, n, ':')) 3502 break; 3503 if (at(p + 1, n, ':')) 3504 break; // "::" 3505 p++; 3506 q = scan(p, n, L_HEX, H_HEX); 3507 if (q <= p) 3508 failExpecting("digits for an IPv6 address", p); 3509 if (at(q, n, '.')) { // Beginning of IPv4 address 3510 p--; 3511 break; 3512 } 3513 if (q > p + 4) 3514 fail("IPv6 hexadecimal digit sequence too long", p); 3515 ipv6byteCount += 2; 3516 p = q; 3517 } 3518 3519 return p; 3520 } 3521 3522 } 3523 3524 }