1/* 2 * Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26package java.net; 27 28import java.io.IOException; 29import java.io.InputStream; 30import java.io.File; 31import java.io.OutputStream; 32import java.util.Hashtable; 33import sun.net.util.IPAddressUtil; 34import sun.net.www.ParseUtil; 35 36/** 37 * The abstract class {@code URLStreamHandler} is the common 38 * superclass for all stream protocol handlers. A stream protocol 39 * handler knows how to make a connection for a particular protocol 40 * type, such as {@code http} or {@code https}. 41 * <p> 42 * In most cases, an instance of a {@code URLStreamHandler} 43 * subclass is not created directly by an application. Rather, the 44 * first time a protocol name is encountered when constructing a 45 * {@code URL}, the appropriate stream protocol handler is 46 * automatically loaded. 47 * 48 * @author James Gosling 49 * @see java.net.URL#URL(java.lang.String, java.lang.String, int, java.lang.String) 50 * @since 1.0 51 */ 52public abstract class URLStreamHandler { 53 /** 54 * Opens a connection to the object referenced by the 55 * {@code URL} argument. 56 * This method should be overridden by a subclass. 57 * 58 * <p>If for the handler's protocol (such as HTTP or JAR), there 59 * exists a public, specialized URLConnection subclass belonging 60 * to one of the following packages or one of their subpackages: 61 * java.lang, java.io, java.util, java.net, the connection 62 * returned will be of that subclass. For example, for HTTP an 63 * HttpURLConnection will be returned, and for JAR a 64 * JarURLConnection will be returned. 65 * 66 * @param u the URL that this connects to. 67 * @return a {@code URLConnection} object for the {@code URL}. 68 * @exception IOException if an I/O error occurs while opening the 69 * connection. 70 */ 71 protected abstract URLConnection openConnection(URL u) throws IOException; 72 73 /** 74 * Same as openConnection(URL), except that the connection will be 75 * made through the specified proxy; Protocol handlers that do not 76 * support proxying will ignore the proxy parameter and make a 77 * normal connection. 78 * 79 * Calling this method preempts the system's default 80 * {@link java.net.ProxySelector ProxySelector} settings. 81 * 82 * @param u the URL that this connects to. 83 * @param p the proxy through which the connection will be made. 84 * If direct connection is desired, Proxy.NO_PROXY 85 * should be specified. 86 * @return a {@code URLConnection} object for the {@code URL}. 87 * @exception IOException if an I/O error occurs while opening the 88 * connection. 89 * @exception IllegalArgumentException if either u or p is null, 90 * or p has the wrong type. 91 * @exception UnsupportedOperationException if the subclass that 92 * implements the protocol doesn't support this method. 93 * @since 1.5 94 */ 95 protected URLConnection openConnection(URL u, Proxy p) throws IOException { 96 throw new UnsupportedOperationException("Method not implemented."); 97 } 98 99 /** 100 * Parses the string representation of a {@code URL} into a 101 * {@code URL} object. 102 * <p> 103 * If there is any inherited context, then it has already been 104 * copied into the {@code URL} argument. 105 * <p> 106 * The {@code parseURL} method of {@code URLStreamHandler} 107 * parses the string representation as if it were an 108 * {@code http} specification. Most URL protocol families have a 109 * similar parsing. A stream protocol handler for a protocol that has 110 * a different syntax must override this routine. 111 * 112 * @param u the {@code URL} to receive the result of parsing 113 * the spec. 114 * @param spec the {@code String} representing the URL that 115 * must be parsed. 116 * @param start the character index at which to begin parsing. This is 117 * just past the '{@code :}' (if there is one) that 118 * specifies the determination of the protocol name. 119 * @param limit the character position to stop parsing at. This is the 120 * end of the string or the position of the 121 * "{@code #}" character, if present. All information 122 * after the sharp sign indicates an anchor. 123 */ 124 protected void parseURL(URL u, String spec, int start, int limit) { 125 // These fields may receive context content if this was relative URL 126 String protocol = u.getProtocol(); 127 String authority = u.getAuthority(); 128 String userInfo = u.getUserInfo(); 129 String host = u.getHost(); 130 int port = u.getPort(); 131 String path = u.getPath(); 132 String query = u.getQuery(); 133 134 // This field has already been parsed 135 String ref = u.getRef(); 136 137 boolean isRelPath = false; 138 boolean queryOnly = false; 139 140// FIX: should not assume query if opaque 141 // Strip off the query part 142 if (start < limit) { 143 int queryStart = spec.indexOf('?'); 144 queryOnly = queryStart == start; 145 if ((queryStart != -1) && (queryStart < limit)) { 146 query = spec.substring(queryStart+1, limit); 147 if (limit > queryStart) 148 limit = queryStart; 149 spec = spec.substring(0, queryStart); 150 } 151 } 152 153 int i = 0; 154 // Parse the authority part if any 155 boolean isUNCName = (start <= limit - 4) && 156 (spec.charAt(start) == '/') && 157 (spec.charAt(start + 1) == '/') && 158 (spec.charAt(start + 2) == '/') && 159 (spec.charAt(start + 3) == '/'); 160 if (!isUNCName && (start <= limit - 2) && (spec.charAt(start) == '/') && 161 (spec.charAt(start + 1) == '/')) { 162 start += 2; 163 i = spec.indexOf('/', start); 164 if (i < 0 || i > limit) { 165 i = spec.indexOf('?', start); 166 if (i < 0 || i > limit) 167 i = limit; 168 } 169 170 host = authority = spec.substring(start, i); 171 172 int ind = authority.indexOf('@'); 173 if (ind != -1) { 174 if (ind != authority.lastIndexOf('@')) { 175 // more than one '@' in authority. This is not server based 176 userInfo = null; 177 host = null; 178 } else { 179 userInfo = authority.substring(0, ind); 180 host = authority.substring(ind+1); 181 } 182 } else { 183 userInfo = null; 184 } 185 if (host != null) { 186 // If the host is surrounded by [ and ] then its an IPv6 187 // literal address as specified in RFC2732 188 if (host.length()>0 && (host.charAt(0) == '[')) { 189 if ((ind = host.indexOf(']')) > 2) { 190 191 String nhost = host ; 192 host = nhost.substring(0,ind+1); 193 if (!IPAddressUtil. 194 isIPv6LiteralAddress(host.substring(1, ind))) { 195 throw new IllegalArgumentException( 196 "Invalid host: "+ host); 197 } 198 199 port = -1 ; 200 if (nhost.length() > ind+1) { 201 if (nhost.charAt(ind+1) == ':') { 202 ++ind ; 203 // port can be null according to RFC2396 204 if (nhost.length() > (ind + 1)) { 205 port = Integer.parseInt(nhost, ind + 1, 206 nhost.length(), 10); 207 } 208 } else { 209 throw new IllegalArgumentException( 210 "Invalid authority field: " + authority); 211 } 212 } 213 } else { 214 throw new IllegalArgumentException( 215 "Invalid authority field: " + authority); 216 } 217 } else { 218 ind = host.indexOf(':'); 219 port = -1; 220 if (ind >= 0) { 221 // port can be null according to RFC2396 222 if (host.length() > (ind + 1)) { 223 port = Integer.parseInt(host, ind + 1, 224 host.length(), 10); 225 } 226 host = host.substring(0, ind); 227 } 228 } 229 } else { 230 host = ""; 231 } 232 if (port < -1) 233 throw new IllegalArgumentException("Invalid port number :" + 234 port); 235 start = i; 236 // If the authority is defined then the path is defined by the 237 // spec only; See RFC 2396 Section 5.2.4. 238 if (authority != null && authority.length() > 0) 239 path = ""; 240 } 241 242 if (host == null) { 243 host = ""; 244 } 245 246 // Parse the file path if any 247 if (start < limit) { 248 if (spec.charAt(start) == '/') { 249 path = spec.substring(start, limit); 250 } else if (path != null && path.length() > 0) { 251 isRelPath = true; 252 int ind = path.lastIndexOf('/'); 253 String seperator = ""; 254 if (ind == -1 && authority != null) 255 seperator = "/"; 256 path = path.substring(0, ind + 1) + seperator + 257 spec.substring(start, limit); 258 259 } else { 260 String seperator = (authority != null) ? "/" : ""; 261 path = seperator + spec.substring(start, limit); 262 } 263 } else if (queryOnly && path != null) { 264 int ind = path.lastIndexOf('/'); 265 if (ind < 0) 266 ind = 0; 267 path = path.substring(0, ind) + "/"; 268 } 269 if (path == null) 270 path = ""; 271 272 if (isRelPath) { 273 // Remove embedded /./ 274 while ((i = path.indexOf("/./")) >= 0) { 275 path = path.substring(0, i) + path.substring(i + 2); 276 } 277 // Remove embedded /../ if possible 278 i = 0; 279 while ((i = path.indexOf("/../", i)) >= 0) { 280 /* 281 * A "/../" will cancel the previous segment and itself, 282 * unless that segment is a "/../" itself 283 * i.e. "/a/b/../c" becomes "/a/c" 284 * but "/../../a" should stay unchanged 285 */ 286 if (i > 0 && (limit = path.lastIndexOf('/', i - 1)) >= 0 && 287 (path.indexOf("/../", limit) != 0)) { 288 path = path.substring(0, limit) + path.substring(i + 3); 289 i = 0; 290 } else { 291 i = i + 3; 292 } 293 } 294 // Remove trailing .. if possible 295 while (path.endsWith("/..")) { 296 i = path.indexOf("/.."); 297 if ((limit = path.lastIndexOf('/', i - 1)) >= 0) { 298 path = path.substring(0, limit+1); 299 } else { 300 break; 301 } 302 } 303 // Remove starting . 304 if (path.startsWith("./") && path.length() > 2) 305 path = path.substring(2); 306 307 // Remove trailing . 308 if (path.endsWith("/.")) 309 path = path.substring(0, path.length() -1); 310 } 311 312 setURL(u, protocol, host, port, authority, userInfo, path, query, ref); 313 } 314 315 /** 316 * Returns the default port for a URL parsed by this handler. This method 317 * is meant to be overidden by handlers with default port numbers. 318 * @return the default port for a {@code URL} parsed by this handler. 319 * @since 1.3 320 */ 321 protected int getDefaultPort() { 322 return -1; 323 } 324 325 /** 326 * Provides the default equals calculation. May be overidden by handlers 327 * for other protocols that have different requirements for equals(). 328 * This method requires that none of its arguments is null. This is 329 * guaranteed by the fact that it is only called by java.net.URL class. 330 * @param u1 a URL object 331 * @param u2 a URL object 332 * @return {@code true} if the two urls are 333 * considered equal, ie. they refer to the same 334 * fragment in the same file. 335 * @since 1.3 336 */ 337 protected boolean equals(URL u1, URL u2) { 338 String ref1 = u1.getRef(); 339 String ref2 = u2.getRef(); 340 return (ref1 == ref2 || (ref1 != null && ref1.equals(ref2))) && 341 sameFile(u1, u2); 342 } 343 344 /** 345 * Provides the default hash calculation. May be overidden by handlers for 346 * other protocols that have different requirements for hashCode 347 * calculation. 348 * @param u a URL object 349 * @return an {@code int} suitable for hash table indexing 350 * @since 1.3 351 */ 352 protected int hashCode(URL u) { 353 int h = 0; 354 355 // Generate the protocol part. 356 String protocol = u.getProtocol(); 357 if (protocol != null) 358 h += protocol.hashCode(); 359 360 // Generate the host part. 361 InetAddress addr = getHostAddress(u); 362 if (addr != null) { 363 h += addr.hashCode(); 364 } else { 365 String host = u.getHost(); 366 if (host != null) 367 h += host.toLowerCase().hashCode(); 368 } 369 370 // Generate the file part. 371 String file = u.getFile(); 372 if (file != null) 373 h += file.hashCode(); 374 375 // Generate the port part. 376 if (u.getPort() == -1) 377 h += getDefaultPort(); 378 else 379 h += u.getPort(); 380 381 // Generate the ref part. 382 String ref = u.getRef(); 383 if (ref != null) 384 h += ref.hashCode(); 385 386 return h; 387 } 388 389 /** 390 * Compare two urls to see whether they refer to the same file, 391 * i.e., having the same protocol, host, port, and path. 392 * This method requires that none of its arguments is null. This is 393 * guaranteed by the fact that it is only called indirectly 394 * by java.net.URL class. 395 * @param u1 a URL object 396 * @param u2 a URL object 397 * @return true if u1 and u2 refer to the same file 398 * @since 1.3 399 */ 400 protected boolean sameFile(URL u1, URL u2) { 401 // Compare the protocols. 402 if (!((u1.getProtocol() == u2.getProtocol()) || 403 (u1.getProtocol() != null && 404 u1.getProtocol().equalsIgnoreCase(u2.getProtocol())))) 405 return false; 406 407 // Compare the files. 408 if (!(u1.getFile() == u2.getFile() || 409 (u1.getFile() != null && u1.getFile().equals(u2.getFile())))) 410 return false; 411 412 // Compare the ports. 413 int port1, port2; 414 port1 = (u1.getPort() != -1) ? u1.getPort() : u1.handler.getDefaultPort(); 415 port2 = (u2.getPort() != -1) ? u2.getPort() : u2.handler.getDefaultPort(); 416 if (port1 != port2) 417 return false; 418 419 // Compare the hosts. 420 if (!hostsEqual(u1, u2)) 421 return false; 422 423 return true; 424 } 425 426 /** 427 * Get the IP address of our host. An empty host field or a DNS failure 428 * will result in a null return. 429 * 430 * @param u a URL object 431 * @return an {@code InetAddress} representing the host 432 * IP address. 433 * @since 1.3 434 */ 435 protected synchronized InetAddress getHostAddress(URL u) { 436 if (u.hostAddress != null) 437 return u.hostAddress; 438 439 String host = u.getHost(); 440 if (host == null || host.equals("")) { 441 return null; 442 } else { 443 try { 444 u.hostAddress = InetAddress.getByName(host); 445 } catch (UnknownHostException ex) { 446 return null; 447 } catch (SecurityException se) { 448 return null; 449 } 450 } 451 return u.hostAddress; 452 } 453 454 /** 455 * Compares the host components of two URLs. 456 * @param u1 the URL of the first host to compare 457 * @param u2 the URL of the second host to compare 458 * @return {@code true} if and only if they 459 * are equal, {@code false} otherwise. 460 * @since 1.3 461 */ 462 protected boolean hostsEqual(URL u1, URL u2) { 463 InetAddress a1 = getHostAddress(u1); 464 InetAddress a2 = getHostAddress(u2); 465 // if we have internet address for both, compare them 466 if (a1 != null && a2 != null) { 467 return a1.equals(a2); 468 // else, if both have host names, compare them 469 } else if (u1.getHost() != null && u2.getHost() != null) 470 return u1.getHost().equalsIgnoreCase(u2.getHost()); 471 else 472 return u1.getHost() == null && u2.getHost() == null; 473 } 474 475 /** 476 * Converts a {@code URL} of a specific protocol to a 477 * {@code String}. 478 * 479 * @param u the URL. 480 * @return a string representation of the {@code URL} argument. 481 */ 482 protected String toExternalForm(URL u) { 483 484 // pre-compute length of StringBuffer 485 int len = u.getProtocol().length() + 1; 486 if (u.getAuthority() != null && u.getAuthority().length() > 0) 487 len += 2 + u.getAuthority().length(); 488 if (u.getPath() != null) { 489 len += u.getPath().length(); 490 } 491 if (u.getQuery() != null) { 492 len += 1 + u.getQuery().length(); 493 } 494 if (u.getRef() != null) 495 len += 1 + u.getRef().length(); 496 497 StringBuilder result = new StringBuilder(len); 498 result.append(u.getProtocol()); 499 result.append(":"); 500 if (u.getAuthority() != null && u.getAuthority().length() > 0) { 501 result.append("//"); 502 result.append(u.getAuthority()); 503 } 504 if (u.getPath() != null) { 505 result.append(u.getPath()); 506 } 507 if (u.getQuery() != null) { 508 result.append('?'); 509 result.append(u.getQuery()); 510 } 511 if (u.getRef() != null) { 512 result.append("#"); 513 result.append(u.getRef()); 514 } 515 return result.toString(); 516 } 517 518 /** 519 * Sets the fields of the {@code URL} argument to the indicated values. 520 * Only classes derived from URLStreamHandler are able 521 * to use this method to set the values of the URL fields. 522 * 523 * @param u the URL to modify. 524 * @param protocol the protocol name. 525 * @param host the remote host value for the URL. 526 * @param port the port on the remote machine. 527 * @param authority the authority part for the URL. 528 * @param userInfo the userInfo part of the URL. 529 * @param path the path component of the URL. 530 * @param query the query part for the URL. 531 * @param ref the reference. 532 * @exception SecurityException if the protocol handler of the URL is 533 * different from this one 534 * @see java.net.URL#set(java.lang.String, java.lang.String, int, java.lang.String, java.lang.String) 535 * @since 1.3 536 */ 537 protected void setURL(URL u, String protocol, String host, int port, 538 String authority, String userInfo, String path, 539 String query, String ref) { 540 if (this != u.handler) { 541 throw new SecurityException("handler for url different from " + 542 "this handler"); 543 } 544 // ensure that no one can reset the protocol on a given URL. 545 u.set(u.getProtocol(), host, port, authority, userInfo, path, query, ref); 546 } 547 548 /** 549 * Sets the fields of the {@code URL} argument to the indicated values. 550 * Only classes derived from URLStreamHandler are able 551 * to use this method to set the values of the URL fields. 552 * 553 * @param u the URL to modify. 554 * @param protocol the protocol name. This value is ignored since 1.2. 555 * @param host the remote host value for the URL. 556 * @param port the port on the remote machine. 557 * @param file the file. 558 * @param ref the reference. 559 * @exception SecurityException if the protocol handler of the URL is 560 * different from this one 561 * @deprecated Use setURL(URL, String, String, int, String, String, String, 562 * String); 563 */ 564 @Deprecated 565 protected void setURL(URL u, String protocol, String host, int port, 566 String file, String ref) { 567 /* 568 * Only old URL handlers call this, so assume that the host 569 * field might contain "user:passwd@host". Fix as necessary. 570 */ 571 String authority = null; 572 String userInfo = null; 573 if (host != null && host.length() != 0) { 574 authority = (port == -1) ? host : host + ":" + port; 575 int at = host.lastIndexOf('@'); 576 if (at != -1) { 577 userInfo = host.substring(0, at); 578 host = host.substring(at+1); 579 } 580 } 581 582 /* 583 * Assume file might contain query part. Fix as necessary. 584 */ 585 String path = null; 586 String query = null; 587 if (file != null) { 588 int q = file.lastIndexOf('?'); 589 if (q != -1) { 590 query = file.substring(q+1); 591 path = file.substring(0, q); 592 } else 593 path = file; 594 } 595 setURL(u, protocol, host, port, authority, userInfo, path, query, ref); 596 } 597} 598