Uri.java revision 61e4248f8f6ae8a8f40550cc0800e5190cd1dc09
1/* 2 * Copyright (C) 2007 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package android.net; 18 19import android.os.Parcel; 20import android.os.Parcelable; 21import android.util.Log; 22 23import java.io.File; 24import java.io.IOException; 25import java.io.UnsupportedEncodingException; 26import java.io.ByteArrayOutputStream; 27import java.net.URLEncoder; 28import java.util.AbstractList; 29import java.util.ArrayList; 30import java.util.Collections; 31import java.util.List; 32import java.util.RandomAccess; 33 34/** 35 * Immutable URI reference. A URI reference includes a URI and a fragment, the 36 * component of the URI following a '#'. Builds and parses URI references 37 * which conform to 38 * <a href="http://www.faqs.org/rfcs/rfc2396.html">RFC 2396</a>. 39 * 40 * <p>In the interest of performance, this class performs little to no 41 * validation. Behavior is undefined for invalid input. This class is very 42 * forgiving--in the face of invalid input, it will return garbage 43 * rather than throw an exception unless otherwise specified. 44 */ 45public abstract class Uri implements Parcelable, Comparable<Uri> { 46 47 /* 48 49 This class aims to do as little up front work as possible. To accomplish 50 that, we vary the implementation dependending on what the user passes in. 51 For example, we have one implementation if the user passes in a 52 URI string (StringUri) and another if the user passes in the 53 individual components (OpaqueUri). 54 55 *Concurrency notes*: Like any truly immutable object, this class is safe 56 for concurrent use. This class uses a caching pattern in some places where 57 it doesn't use volatile or synchronized. This is safe to do with ints 58 because getting or setting an int is atomic. It's safe to do with a String 59 because the internal fields are final and the memory model guarantees other 60 threads won't see a partially initialized instance. We are not guaranteed 61 that some threads will immediately see changes from other threads on 62 certain platforms, but we don't mind if those threads reconstruct the 63 cached result. As a result, we get thread safe caching with no concurrency 64 overhead, which means the most common case, access from a single thread, 65 is as fast as possible. 66 67 From the Java Language spec.: 68 69 "17.5 Final Field Semantics 70 71 ... when the object is seen by another thread, that thread will always 72 see the correctly constructed version of that object's final fields. 73 It will also see versions of any object or array referenced by 74 those final fields that are at least as up-to-date as the final fields 75 are." 76 77 In that same vein, all non-transient fields within Uri 78 implementations should be final and immutable so as to ensure true 79 immutability for clients even when they don't use proper concurrency 80 control. 81 82 For reference, from RFC 2396: 83 84 "4.3. Parsing a URI Reference 85 86 A URI reference is typically parsed according to the four main 87 components and fragment identifier in order to determine what 88 components are present and whether the reference is relative or 89 absolute. The individual components are then parsed for their 90 subparts and, if not opaque, to verify their validity. 91 92 Although the BNF defines what is allowed in each component, it is 93 ambiguous in terms of differentiating between an authority component 94 and a path component that begins with two slash characters. The 95 greedy algorithm is used for disambiguation: the left-most matching 96 rule soaks up as much of the URI reference string as it is capable of 97 matching. In other words, the authority component wins." 98 99 The "four main components" of a hierarchical URI consist of 100 <scheme>://<authority><path>?<query> 101 102 */ 103 104 /** Log tag. */ 105 private static final String LOG = Uri.class.getSimpleName(); 106 107 /** 108 * NOTE: EMPTY accesses this field during its own initialization, so this 109 * field *must* be initialized first, or else EMPTY will see a null value! 110 * 111 * Placeholder for strings which haven't been cached. This enables us 112 * to cache null. We intentionally create a new String instance so we can 113 * compare its identity and there is no chance we will confuse it with 114 * user data. 115 */ 116 @SuppressWarnings("RedundantStringConstructorCall") 117 private static final String NOT_CACHED = new String("NOT CACHED"); 118 119 /** 120 * The empty URI, equivalent to "". 121 */ 122 public static final Uri EMPTY = new HierarchicalUri(null, Part.NULL, 123 PathPart.EMPTY, Part.NULL, Part.NULL); 124 125 /** 126 * Prevents external subclassing. 127 */ 128 private Uri() {} 129 130 /** 131 * Returns true if this URI is hierarchical like "http://google.com". 132 * Absolute URIs are hierarchical if the scheme-specific part starts with 133 * a '/'. Relative URIs are always hierarchical. 134 */ 135 public abstract boolean isHierarchical(); 136 137 /** 138 * Returns true if this URI is opaque like "mailto:nobody@google.com". The 139 * scheme-specific part of an opaque URI cannot start with a '/'. 140 */ 141 public boolean isOpaque() { 142 return !isHierarchical(); 143 } 144 145 /** 146 * Returns true if this URI is relative, i.e. if it doesn't contain an 147 * explicit scheme. 148 * 149 * @return true if this URI is relative, false if it's absolute 150 */ 151 public abstract boolean isRelative(); 152 153 /** 154 * Returns true if this URI is absolute, i.e. if it contains an 155 * explicit scheme. 156 * 157 * @return true if this URI is absolute, false if it's relative 158 */ 159 public boolean isAbsolute() { 160 return !isRelative(); 161 } 162 163 /** 164 * Gets the scheme of this URI. Example: "http" 165 * 166 * @return the scheme or null if this is a relative URI 167 */ 168 public abstract String getScheme(); 169 170 /** 171 * Gets the scheme-specific part of this URI, i.e. everything between the 172 * scheme separator ':' and the fragment separator '#'. If this is a 173 * relative URI, this method returns the entire URI. Decodes escaped octets. 174 * 175 * <p>Example: "//www.google.com/search?q=android" 176 * 177 * @return the decoded scheme-specific-part 178 */ 179 public abstract String getSchemeSpecificPart(); 180 181 /** 182 * Gets the scheme-specific part of this URI, i.e. everything between the 183 * scheme separator ':' and the fragment separator '#'. If this is a 184 * relative URI, this method returns the entire URI. Leaves escaped octets 185 * intact. 186 * 187 * <p>Example: "//www.google.com/search?q=android" 188 * 189 * @return the decoded scheme-specific-part 190 */ 191 public abstract String getEncodedSchemeSpecificPart(); 192 193 /** 194 * Gets the decoded authority part of this URI. For 195 * server addresses, the authority is structured as follows: 196 * {@code [ userinfo '@' ] host [ ':' port ]} 197 * 198 * <p>Examples: "google.com", "bob@google.com:80" 199 * 200 * @return the authority for this URI or null if not present 201 */ 202 public abstract String getAuthority(); 203 204 /** 205 * Gets the encoded authority part of this URI. For 206 * server addresses, the authority is structured as follows: 207 * {@code [ userinfo '@' ] host [ ':' port ]} 208 * 209 * <p>Examples: "google.com", "bob@google.com:80" 210 * 211 * @return the authority for this URI or null if not present 212 */ 213 public abstract String getEncodedAuthority(); 214 215 /** 216 * Gets the decoded user information from the authority. 217 * For example, if the authority is "nobody@google.com", this method will 218 * return "nobody". 219 * 220 * @return the user info for this URI or null if not present 221 */ 222 public abstract String getUserInfo(); 223 224 /** 225 * Gets the encoded user information from the authority. 226 * For example, if the authority is "nobody@google.com", this method will 227 * return "nobody". 228 * 229 * @return the user info for this URI or null if not present 230 */ 231 public abstract String getEncodedUserInfo(); 232 233 /** 234 * Gets the encoded host from the authority for this URI. For example, 235 * if the authority is "bob@google.com", this method will return 236 * "google.com". 237 * 238 * @return the host for this URI or null if not present 239 */ 240 public abstract String getHost(); 241 242 /** 243 * Gets the port from the authority for this URI. For example, 244 * if the authority is "google.com:80", this method will return 80. 245 * 246 * @return the port for this URI or -1 if invalid or not present 247 */ 248 public abstract int getPort(); 249 250 /** 251 * Gets the decoded path. 252 * 253 * @return the decoded path, or null if this is not a hierarchical URI 254 * (like "mailto:nobody@google.com") or the URI is invalid 255 */ 256 public abstract String getPath(); 257 258 /** 259 * Gets the encoded path. 260 * 261 * @return the encoded path, or null if this is not a hierarchical URI 262 * (like "mailto:nobody@google.com") or the URI is invalid 263 */ 264 public abstract String getEncodedPath(); 265 266 /** 267 * Gets the decoded query component from this URI. The query comes after 268 * the query separator ('?') and before the fragment separator ('#'). This 269 * method would return "q=android" for 270 * "http://www.google.com/search?q=android". 271 * 272 * @return the decoded query or null if there isn't one 273 */ 274 public abstract String getQuery(); 275 276 /** 277 * Gets the encoded query component from this URI. The query comes after 278 * the query separator ('?') and before the fragment separator ('#'). This 279 * method would return "q=android" for 280 * "http://www.google.com/search?q=android". 281 * 282 * @return the encoded query or null if there isn't one 283 */ 284 public abstract String getEncodedQuery(); 285 286 /** 287 * Gets the decoded fragment part of this URI, everything after the '#'. 288 * 289 * @return the decoded fragment or null if there isn't one 290 */ 291 public abstract String getFragment(); 292 293 /** 294 * Gets the encoded fragment part of this URI, everything after the '#'. 295 * 296 * @return the encoded fragment or null if there isn't one 297 */ 298 public abstract String getEncodedFragment(); 299 300 /** 301 * Gets the decoded path segments. 302 * 303 * @return decoded path segments, each without a leading or trailing '/' 304 */ 305 public abstract List<String> getPathSegments(); 306 307 /** 308 * Gets the decoded last segment in the path. 309 * 310 * @return the decoded last segment or null if the path is empty 311 */ 312 public abstract String getLastPathSegment(); 313 314 /** 315 * Compares this Uri to another object for equality. Returns true if the 316 * encoded string representations of this Uri and the given Uri are 317 * equal. Case counts. Paths are not normalized. If one Uri specifies a 318 * default port explicitly and the other leaves it implicit, they will not 319 * be considered equal. 320 */ 321 public boolean equals(Object o) { 322 if (!(o instanceof Uri)) { 323 return false; 324 } 325 326 Uri other = (Uri) o; 327 328 return toString().equals(other.toString()); 329 } 330 331 /** 332 * Hashes the encoded string represention of this Uri consistently with 333 * {@link #equals(Object)}. 334 */ 335 public int hashCode() { 336 return toString().hashCode(); 337 } 338 339 /** 340 * Compares the string representation of this Uri with that of 341 * another. 342 */ 343 public int compareTo(Uri other) { 344 return toString().compareTo(other.toString()); 345 } 346 347 /** 348 * Returns the encoded string representation of this URI. 349 * Example: "http://google.com/" 350 */ 351 public abstract String toString(); 352 353 /** 354 * Constructs a new builder, copying the attributes from this Uri. 355 */ 356 public abstract Builder buildUpon(); 357 358 /** Index of a component which was not found. */ 359 private final static int NOT_FOUND = -1; 360 361 /** Placeholder value for an index which hasn't been calculated yet. */ 362 private final static int NOT_CALCULATED = -2; 363 364 /** 365 * Error message presented when a user tries to treat an opaque URI as 366 * hierarchical. 367 */ 368 private static final String NOT_HIERARCHICAL 369 = "This isn't a hierarchical URI."; 370 371 /** Default encoding. */ 372 private static final String DEFAULT_ENCODING = "UTF-8"; 373 374 /** 375 * Creates a Uri which parses the given encoded URI string. 376 * 377 * @param uriString an RFC 2396-compliant, encoded URI 378 * @throws NullPointerException if uriString is null 379 * @return Uri for this given uri string 380 */ 381 public static Uri parse(String uriString) { 382 return new StringUri(uriString); 383 } 384 385 /** 386 * Creates a Uri from a file. The URI has the form 387 * "file://<absolute path>". Encodes path characters with the exception of 388 * '/'. 389 * 390 * <p>Example: "file:///tmp/android.txt" 391 * 392 * @throws NullPointerException if file is null 393 * @return a Uri for the given file 394 */ 395 public static Uri fromFile(File file) { 396 if (file == null) { 397 throw new NullPointerException("file"); 398 } 399 400 PathPart path = PathPart.fromDecoded(file.getAbsolutePath()); 401 return new HierarchicalUri( 402 "file", Part.EMPTY, path, Part.NULL, Part.NULL); 403 } 404 405 /** 406 * An implementation which wraps a String URI. This URI can be opaque or 407 * hierarchical, but we extend AbstractHierarchicalUri in case we need 408 * the hierarchical functionality. 409 */ 410 private static class StringUri extends AbstractHierarchicalUri { 411 412 /** Used in parcelling. */ 413 static final int TYPE_ID = 1; 414 415 /** URI string representation. */ 416 private final String uriString; 417 418 private StringUri(String uriString) { 419 if (uriString == null) { 420 throw new NullPointerException("uriString"); 421 } 422 423 this.uriString = uriString; 424 } 425 426 static Uri readFrom(Parcel parcel) { 427 return new StringUri(parcel.readString()); 428 } 429 430 public int describeContents() { 431 return 0; 432 } 433 434 public void writeToParcel(Parcel parcel, int flags) { 435 parcel.writeInt(TYPE_ID); 436 parcel.writeString(uriString); 437 } 438 439 /** Cached scheme separator index. */ 440 private volatile int cachedSsi = NOT_CALCULATED; 441 442 /** Finds the first ':'. Returns -1 if none found. */ 443 private int findSchemeSeparator() { 444 return cachedSsi == NOT_CALCULATED 445 ? cachedSsi = uriString.indexOf(':') 446 : cachedSsi; 447 } 448 449 /** Cached fragment separator index. */ 450 private volatile int cachedFsi = NOT_CALCULATED; 451 452 /** Finds the first '#'. Returns -1 if none found. */ 453 private int findFragmentSeparator() { 454 return cachedFsi == NOT_CALCULATED 455 ? cachedFsi = uriString.indexOf('#', findSchemeSeparator()) 456 : cachedFsi; 457 } 458 459 public boolean isHierarchical() { 460 int ssi = findSchemeSeparator(); 461 462 if (ssi == NOT_FOUND) { 463 // All relative URIs are hierarchical. 464 return true; 465 } 466 467 if (uriString.length() == ssi + 1) { 468 // No ssp. 469 return false; 470 } 471 472 // If the ssp starts with a '/', this is hierarchical. 473 return uriString.charAt(ssi + 1) == '/'; 474 } 475 476 public boolean isRelative() { 477 // Note: We return true if the index is 0 478 return findSchemeSeparator() == NOT_FOUND; 479 } 480 481 private volatile String scheme = NOT_CACHED; 482 483 public String getScheme() { 484 @SuppressWarnings("StringEquality") 485 boolean cached = (scheme != NOT_CACHED); 486 return cached ? scheme : (scheme = parseScheme()); 487 } 488 489 private String parseScheme() { 490 int ssi = findSchemeSeparator(); 491 return ssi == NOT_FOUND ? null : uriString.substring(0, ssi); 492 } 493 494 private Part ssp; 495 496 private Part getSsp() { 497 return ssp == null ? ssp = Part.fromEncoded(parseSsp()) : ssp; 498 } 499 500 public String getEncodedSchemeSpecificPart() { 501 return getSsp().getEncoded(); 502 } 503 504 public String getSchemeSpecificPart() { 505 return getSsp().getDecoded(); 506 } 507 508 private String parseSsp() { 509 int ssi = findSchemeSeparator(); 510 int fsi = findFragmentSeparator(); 511 512 // Return everything between ssi and fsi. 513 return fsi == NOT_FOUND 514 ? uriString.substring(ssi + 1) 515 : uriString.substring(ssi + 1, fsi); 516 } 517 518 private Part authority; 519 520 private Part getAuthorityPart() { 521 if (authority == null) { 522 String encodedAuthority 523 = parseAuthority(this.uriString, findSchemeSeparator()); 524 return authority = Part.fromEncoded(encodedAuthority); 525 } 526 527 return authority; 528 } 529 530 public String getEncodedAuthority() { 531 return getAuthorityPart().getEncoded(); 532 } 533 534 public String getAuthority() { 535 return getAuthorityPart().getDecoded(); 536 } 537 538 private PathPart path; 539 540 private PathPart getPathPart() { 541 return path == null 542 ? path = PathPart.fromEncoded(parsePath()) 543 : path; 544 } 545 546 public String getPath() { 547 return getPathPart().getDecoded(); 548 } 549 550 public String getEncodedPath() { 551 return getPathPart().getEncoded(); 552 } 553 554 public List<String> getPathSegments() { 555 return getPathPart().getPathSegments(); 556 } 557 558 private String parsePath() { 559 String uriString = this.uriString; 560 int ssi = findSchemeSeparator(); 561 562 // If the URI is absolute. 563 if (ssi > -1) { 564 // Is there anything after the ':'? 565 boolean schemeOnly = ssi + 1 == uriString.length(); 566 if (schemeOnly) { 567 // Opaque URI. 568 return null; 569 } 570 571 // A '/' after the ':' means this is hierarchical. 572 if (uriString.charAt(ssi + 1) != '/') { 573 // Opaque URI. 574 return null; 575 } 576 } else { 577 // All relative URIs are hierarchical. 578 } 579 580 return parsePath(uriString, ssi); 581 } 582 583 private Part query; 584 585 private Part getQueryPart() { 586 return query == null 587 ? query = Part.fromEncoded(parseQuery()) : query; 588 } 589 590 public String getEncodedQuery() { 591 return getQueryPart().getEncoded(); 592 } 593 594 private String parseQuery() { 595 // It doesn't make sense to cache this index. We only ever 596 // calculate it once. 597 int qsi = uriString.indexOf('?', findSchemeSeparator()); 598 if (qsi == NOT_FOUND) { 599 return null; 600 } 601 602 int fsi = findFragmentSeparator(); 603 604 if (fsi == NOT_FOUND) { 605 return uriString.substring(qsi + 1); 606 } 607 608 if (fsi < qsi) { 609 // Invalid. 610 return null; 611 } 612 613 return uriString.substring(qsi + 1, fsi); 614 } 615 616 public String getQuery() { 617 return getQueryPart().getDecoded(); 618 } 619 620 private Part fragment; 621 622 private Part getFragmentPart() { 623 return fragment == null 624 ? fragment = Part.fromEncoded(parseFragment()) : fragment; 625 } 626 627 public String getEncodedFragment() { 628 return getFragmentPart().getEncoded(); 629 } 630 631 private String parseFragment() { 632 int fsi = findFragmentSeparator(); 633 return fsi == NOT_FOUND ? null : uriString.substring(fsi + 1); 634 } 635 636 public String getFragment() { 637 return getFragmentPart().getDecoded(); 638 } 639 640 public String toString() { 641 return uriString; 642 } 643 644 /** 645 * Parses an authority out of the given URI string. 646 * 647 * @param uriString URI string 648 * @param ssi scheme separator index, -1 for a relative URI 649 * 650 * @return the authority or null if none is found 651 */ 652 static String parseAuthority(String uriString, int ssi) { 653 int length = uriString.length(); 654 655 // If "//" follows the scheme separator, we have an authority. 656 if (length > ssi + 2 657 && uriString.charAt(ssi + 1) == '/' 658 && uriString.charAt(ssi + 2) == '/') { 659 // We have an authority. 660 661 // Look for the start of the path, query, or fragment, or the 662 // end of the string. 663 int end = ssi + 3; 664 LOOP: while (end < length) { 665 switch (uriString.charAt(end)) { 666 case '/': // Start of path 667 case '?': // Start of query 668 case '#': // Start of fragment 669 break LOOP; 670 } 671 end++; 672 } 673 674 return uriString.substring(ssi + 3, end); 675 } else { 676 return null; 677 } 678 679 } 680 681 /** 682 * Parses a path out of this given URI string. 683 * 684 * @param uriString URI string 685 * @param ssi scheme separator index, -1 for a relative URI 686 * 687 * @return the path 688 */ 689 static String parsePath(String uriString, int ssi) { 690 int length = uriString.length(); 691 692 // Find start of path. 693 int pathStart; 694 if (length > ssi + 2 695 && uriString.charAt(ssi + 1) == '/' 696 && uriString.charAt(ssi + 2) == '/') { 697 // Skip over authority to path. 698 pathStart = ssi + 3; 699 LOOP: while (pathStart < length) { 700 switch (uriString.charAt(pathStart)) { 701 case '?': // Start of query 702 case '#': // Start of fragment 703 return ""; // Empty path. 704 case '/': // Start of path! 705 break LOOP; 706 } 707 pathStart++; 708 } 709 } else { 710 // Path starts immediately after scheme separator. 711 pathStart = ssi + 1; 712 } 713 714 // Find end of path. 715 int pathEnd = pathStart; 716 LOOP: while (pathEnd < length) { 717 switch (uriString.charAt(pathEnd)) { 718 case '?': // Start of query 719 case '#': // Start of fragment 720 break LOOP; 721 } 722 pathEnd++; 723 } 724 725 return uriString.substring(pathStart, pathEnd); 726 } 727 728 public Builder buildUpon() { 729 if (isHierarchical()) { 730 return new Builder() 731 .scheme(getScheme()) 732 .authority(getAuthorityPart()) 733 .path(getPathPart()) 734 .query(getQueryPart()) 735 .fragment(getFragmentPart()); 736 } else { 737 return new Builder() 738 .scheme(getScheme()) 739 .opaquePart(getSsp()) 740 .fragment(getFragmentPart()); 741 } 742 } 743 } 744 745 /** 746 * Creates an opaque Uri from the given components. Encodes the ssp 747 * which means this method cannot be used to create hierarchical URIs. 748 * 749 * @param scheme of the URI 750 * @param ssp scheme-specific-part, everything between the 751 * scheme separator (':') and the fragment separator ('#'), which will 752 * get encoded 753 * @param fragment fragment, everything after the '#', null if undefined, 754 * will get encoded 755 * 756 * @throws NullPointerException if scheme or ssp is null 757 * @return Uri composed of the given scheme, ssp, and fragment 758 * 759 * @see Builder if you don't want the ssp and fragment to be encoded 760 */ 761 public static Uri fromParts(String scheme, String ssp, 762 String fragment) { 763 if (scheme == null) { 764 throw new NullPointerException("scheme"); 765 } 766 if (ssp == null) { 767 throw new NullPointerException("ssp"); 768 } 769 770 return new OpaqueUri(scheme, Part.fromDecoded(ssp), 771 Part.fromDecoded(fragment)); 772 } 773 774 /** 775 * Opaque URI. 776 */ 777 private static class OpaqueUri extends Uri { 778 779 /** Used in parcelling. */ 780 static final int TYPE_ID = 2; 781 782 private final String scheme; 783 private final Part ssp; 784 private final Part fragment; 785 786 private OpaqueUri(String scheme, Part ssp, Part fragment) { 787 this.scheme = scheme; 788 this.ssp = ssp; 789 this.fragment = fragment == null ? Part.NULL : fragment; 790 } 791 792 static Uri readFrom(Parcel parcel) { 793 return new OpaqueUri( 794 parcel.readString(), 795 Part.readFrom(parcel), 796 Part.readFrom(parcel) 797 ); 798 } 799 800 public int describeContents() { 801 return 0; 802 } 803 804 public void writeToParcel(Parcel parcel, int flags) { 805 parcel.writeInt(TYPE_ID); 806 parcel.writeString(scheme); 807 ssp.writeTo(parcel); 808 fragment.writeTo(parcel); 809 } 810 811 public boolean isHierarchical() { 812 return false; 813 } 814 815 public boolean isRelative() { 816 return scheme == null; 817 } 818 819 public String getScheme() { 820 return this.scheme; 821 } 822 823 public String getEncodedSchemeSpecificPart() { 824 return ssp.getEncoded(); 825 } 826 827 public String getSchemeSpecificPart() { 828 return ssp.getDecoded(); 829 } 830 831 public String getAuthority() { 832 return null; 833 } 834 835 public String getEncodedAuthority() { 836 return null; 837 } 838 839 public String getPath() { 840 return null; 841 } 842 843 public String getEncodedPath() { 844 return null; 845 } 846 847 public String getQuery() { 848 return null; 849 } 850 851 public String getEncodedQuery() { 852 return null; 853 } 854 855 public String getFragment() { 856 return fragment.getDecoded(); 857 } 858 859 public String getEncodedFragment() { 860 return fragment.getEncoded(); 861 } 862 863 public List<String> getPathSegments() { 864 return Collections.emptyList(); 865 } 866 867 public String getLastPathSegment() { 868 return null; 869 } 870 871 public String getUserInfo() { 872 return null; 873 } 874 875 public String getEncodedUserInfo() { 876 return null; 877 } 878 879 public String getHost() { 880 return null; 881 } 882 883 public int getPort() { 884 return -1; 885 } 886 887 private volatile String cachedString = NOT_CACHED; 888 889 public String toString() { 890 @SuppressWarnings("StringEquality") 891 boolean cached = cachedString != NOT_CACHED; 892 if (cached) { 893 return cachedString; 894 } 895 896 StringBuilder sb = new StringBuilder(); 897 898 sb.append(scheme).append(':'); 899 sb.append(getEncodedSchemeSpecificPart()); 900 901 if (!fragment.isEmpty()) { 902 sb.append('#').append(fragment.getEncoded()); 903 } 904 905 return cachedString = sb.toString(); 906 } 907 908 public Builder buildUpon() { 909 return new Builder() 910 .scheme(this.scheme) 911 .opaquePart(this.ssp) 912 .fragment(this.fragment); 913 } 914 } 915 916 /** 917 * Wrapper for path segment array. 918 */ 919 static class PathSegments extends AbstractList<String> 920 implements RandomAccess { 921 922 static final PathSegments EMPTY = new PathSegments(null, 0); 923 924 final String[] segments; 925 final int size; 926 927 PathSegments(String[] segments, int size) { 928 this.segments = segments; 929 this.size = size; 930 } 931 932 public String get(int index) { 933 if (index >= size) { 934 throw new IndexOutOfBoundsException(); 935 } 936 937 return segments[index]; 938 } 939 940 public int size() { 941 return this.size; 942 } 943 } 944 945 /** 946 * Builds PathSegments. 947 */ 948 static class PathSegmentsBuilder { 949 950 String[] segments; 951 int size = 0; 952 953 void add(String segment) { 954 if (segments == null) { 955 segments = new String[4]; 956 } else if (size + 1 == segments.length) { 957 String[] expanded = new String[segments.length * 2]; 958 System.arraycopy(segments, 0, expanded, 0, segments.length); 959 segments = expanded; 960 } 961 962 segments[size++] = segment; 963 } 964 965 PathSegments build() { 966 if (segments == null) { 967 return PathSegments.EMPTY; 968 } 969 970 try { 971 return new PathSegments(segments, size); 972 } finally { 973 // Makes sure this doesn't get reused. 974 segments = null; 975 } 976 } 977 } 978 979 /** 980 * Support for hierarchical URIs. 981 */ 982 private abstract static class AbstractHierarchicalUri extends Uri { 983 984 public String getLastPathSegment() { 985 // TODO: If we haven't parsed all of the segments already, just 986 // grab the last one directly so we only allocate one string. 987 988 List<String> segments = getPathSegments(); 989 int size = segments.size(); 990 if (size == 0) { 991 return null; 992 } 993 return segments.get(size - 1); 994 } 995 996 private Part userInfo; 997 998 private Part getUserInfoPart() { 999 return userInfo == null 1000 ? userInfo = Part.fromEncoded(parseUserInfo()) : userInfo; 1001 } 1002 1003 public final String getEncodedUserInfo() { 1004 return getUserInfoPart().getEncoded(); 1005 } 1006 1007 private String parseUserInfo() { 1008 String authority = getEncodedAuthority(); 1009 if (authority == null) { 1010 return null; 1011 } 1012 1013 int end = authority.indexOf('@'); 1014 return end == NOT_FOUND ? null : authority.substring(0, end); 1015 } 1016 1017 public String getUserInfo() { 1018 return getUserInfoPart().getDecoded(); 1019 } 1020 1021 private volatile String host = NOT_CACHED; 1022 1023 public String getHost() { 1024 @SuppressWarnings("StringEquality") 1025 boolean cached = (host != NOT_CACHED); 1026 return cached ? host 1027 : (host = parseHost()); 1028 } 1029 1030 private String parseHost() { 1031 String authority = getAuthority(); 1032 if (authority == null) { 1033 return null; 1034 } 1035 1036 // Parse out user info and then port. 1037 int userInfoSeparator = authority.indexOf('@'); 1038 int portSeparator = authority.indexOf(':', userInfoSeparator); 1039 1040 return portSeparator == NOT_FOUND 1041 ? authority.substring(userInfoSeparator + 1) 1042 : authority.substring(userInfoSeparator + 1, portSeparator); 1043 } 1044 1045 private volatile int port = NOT_CALCULATED; 1046 1047 public int getPort() { 1048 return port == NOT_CALCULATED 1049 ? port = parsePort() 1050 : port; 1051 } 1052 1053 private int parsePort() { 1054 String authority = getAuthority(); 1055 if (authority == null) { 1056 return -1; 1057 } 1058 1059 // Make sure we look for the port separtor *after* the user info 1060 // separator. We have URLs with a ':' in the user info. 1061 int userInfoSeparator = authority.indexOf('@'); 1062 int portSeparator = authority.indexOf(':', userInfoSeparator); 1063 1064 if (portSeparator == NOT_FOUND) { 1065 return -1; 1066 } 1067 1068 String portString = authority.substring(portSeparator + 1); 1069 try { 1070 return Integer.parseInt(portString); 1071 } catch (NumberFormatException e) { 1072 Log.w(LOG, "Error parsing port string.", e); 1073 return -1; 1074 } 1075 } 1076 } 1077 1078 /** 1079 * Hierarchical Uri. 1080 */ 1081 private static class HierarchicalUri extends AbstractHierarchicalUri { 1082 1083 /** Used in parcelling. */ 1084 static final int TYPE_ID = 3; 1085 1086 private final String scheme; // can be null 1087 private final Part authority; 1088 private final PathPart path; 1089 private final Part query; 1090 private final Part fragment; 1091 1092 private HierarchicalUri(String scheme, Part authority, PathPart path, 1093 Part query, Part fragment) { 1094 this.scheme = scheme; 1095 this.authority = Part.nonNull(authority); 1096 this.path = path == null ? PathPart.NULL : path; 1097 this.query = Part.nonNull(query); 1098 this.fragment = Part.nonNull(fragment); 1099 } 1100 1101 static Uri readFrom(Parcel parcel) { 1102 return new HierarchicalUri( 1103 parcel.readString(), 1104 Part.readFrom(parcel), 1105 PathPart.readFrom(parcel), 1106 Part.readFrom(parcel), 1107 Part.readFrom(parcel) 1108 ); 1109 } 1110 1111 public int describeContents() { 1112 return 0; 1113 } 1114 1115 public void writeToParcel(Parcel parcel, int flags) { 1116 parcel.writeInt(TYPE_ID); 1117 parcel.writeString(scheme); 1118 authority.writeTo(parcel); 1119 path.writeTo(parcel); 1120 query.writeTo(parcel); 1121 fragment.writeTo(parcel); 1122 } 1123 1124 public boolean isHierarchical() { 1125 return true; 1126 } 1127 1128 public boolean isRelative() { 1129 return scheme == null; 1130 } 1131 1132 public String getScheme() { 1133 return scheme; 1134 } 1135 1136 private Part ssp; 1137 1138 private Part getSsp() { 1139 return ssp == null 1140 ? ssp = Part.fromEncoded(makeSchemeSpecificPart()) : ssp; 1141 } 1142 1143 public String getEncodedSchemeSpecificPart() { 1144 return getSsp().getEncoded(); 1145 } 1146 1147 public String getSchemeSpecificPart() { 1148 return getSsp().getDecoded(); 1149 } 1150 1151 /** 1152 * Creates the encoded scheme-specific part from its sub parts. 1153 */ 1154 private String makeSchemeSpecificPart() { 1155 StringBuilder builder = new StringBuilder(); 1156 appendSspTo(builder); 1157 return builder.toString(); 1158 } 1159 1160 private void appendSspTo(StringBuilder builder) { 1161 String encodedAuthority = authority.getEncoded(); 1162 if (encodedAuthority != null) { 1163 // Even if the authority is "", we still want to append "//". 1164 builder.append("//").append(encodedAuthority); 1165 } 1166 1167 String encodedPath = path.getEncoded(); 1168 if (encodedPath != null) { 1169 builder.append(encodedPath); 1170 } 1171 1172 if (!query.isEmpty()) { 1173 builder.append('?').append(query.getEncoded()); 1174 } 1175 } 1176 1177 public String getAuthority() { 1178 return this.authority.getDecoded(); 1179 } 1180 1181 public String getEncodedAuthority() { 1182 return this.authority.getEncoded(); 1183 } 1184 1185 public String getEncodedPath() { 1186 return this.path.getEncoded(); 1187 } 1188 1189 public String getPath() { 1190 return this.path.getDecoded(); 1191 } 1192 1193 public String getQuery() { 1194 return this.query.getDecoded(); 1195 } 1196 1197 public String getEncodedQuery() { 1198 return this.query.getEncoded(); 1199 } 1200 1201 public String getFragment() { 1202 return this.fragment.getDecoded(); 1203 } 1204 1205 public String getEncodedFragment() { 1206 return this.fragment.getEncoded(); 1207 } 1208 1209 public List<String> getPathSegments() { 1210 return this.path.getPathSegments(); 1211 } 1212 1213 private volatile String uriString = NOT_CACHED; 1214 1215 @Override 1216 public String toString() { 1217 @SuppressWarnings("StringEquality") 1218 boolean cached = (uriString != NOT_CACHED); 1219 return cached ? uriString 1220 : (uriString = makeUriString()); 1221 } 1222 1223 private String makeUriString() { 1224 StringBuilder builder = new StringBuilder(); 1225 1226 if (scheme != null) { 1227 builder.append(scheme).append(':'); 1228 } 1229 1230 appendSspTo(builder); 1231 1232 if (!fragment.isEmpty()) { 1233 builder.append('#').append(fragment.getEncoded()); 1234 } 1235 1236 return builder.toString(); 1237 } 1238 1239 public Builder buildUpon() { 1240 return new Builder() 1241 .scheme(scheme) 1242 .authority(authority) 1243 .path(path) 1244 .query(query) 1245 .fragment(fragment); 1246 } 1247 } 1248 1249 /** 1250 * Helper class for building or manipulating URI references. Not safe for 1251 * concurrent use. 1252 * 1253 * <p>An absolute hierarchical URI reference follows the pattern: 1254 * {@code <scheme>://<authority><absolute path>?<query>#<fragment>} 1255 * 1256 * <p>Relative URI references (which are always hierarchical) follow one 1257 * of two patterns: {@code <relative or absolute path>?<query>#<fragment>} 1258 * or {@code //<authority><absolute path>?<query>#<fragment>} 1259 * 1260 * <p>An opaque URI follows this pattern: 1261 * {@code <scheme>:<opaque part>#<fragment>} 1262 */ 1263 public static final class Builder { 1264 1265 private String scheme; 1266 private Part opaquePart; 1267 private Part authority; 1268 private PathPart path; 1269 private Part query; 1270 private Part fragment; 1271 1272 /** 1273 * Constructs a new Builder. 1274 */ 1275 public Builder() {} 1276 1277 /** 1278 * Sets the scheme. 1279 * 1280 * @param scheme name or {@code null} if this is a relative Uri 1281 */ 1282 public Builder scheme(String scheme) { 1283 this.scheme = scheme; 1284 return this; 1285 } 1286 1287 Builder opaquePart(Part opaquePart) { 1288 this.opaquePart = opaquePart; 1289 return this; 1290 } 1291 1292 /** 1293 * Encodes and sets the given opaque scheme-specific-part. 1294 * 1295 * @param opaquePart decoded opaque part 1296 */ 1297 public Builder opaquePart(String opaquePart) { 1298 return opaquePart(Part.fromDecoded(opaquePart)); 1299 } 1300 1301 /** 1302 * Sets the previously encoded opaque scheme-specific-part. 1303 * 1304 * @param opaquePart encoded opaque part 1305 */ 1306 public Builder encodedOpaquePart(String opaquePart) { 1307 return opaquePart(Part.fromEncoded(opaquePart)); 1308 } 1309 1310 Builder authority(Part authority) { 1311 // This URI will be hierarchical. 1312 this.opaquePart = null; 1313 1314 this.authority = authority; 1315 return this; 1316 } 1317 1318 /** 1319 * Encodes and sets the authority. 1320 */ 1321 public Builder authority(String authority) { 1322 return authority(Part.fromDecoded(authority)); 1323 } 1324 1325 /** 1326 * Sets the previously encoded authority. 1327 */ 1328 public Builder encodedAuthority(String authority) { 1329 return authority(Part.fromEncoded(authority)); 1330 } 1331 1332 Builder path(PathPart path) { 1333 // This URI will be hierarchical. 1334 this.opaquePart = null; 1335 1336 this.path = path; 1337 return this; 1338 } 1339 1340 /** 1341 * Sets the path. Leaves '/' characters intact but encodes others as 1342 * necessary. 1343 * 1344 * <p>If the path is not null and doesn't start with a '/', and if 1345 * you specify a scheme and/or authority, the builder will prepend the 1346 * given path with a '/'. 1347 */ 1348 public Builder path(String path) { 1349 return path(PathPart.fromDecoded(path)); 1350 } 1351 1352 /** 1353 * Sets the previously encoded path. 1354 * 1355 * <p>If the path is not null and doesn't start with a '/', and if 1356 * you specify a scheme and/or authority, the builder will prepend the 1357 * given path with a '/'. 1358 */ 1359 public Builder encodedPath(String path) { 1360 return path(PathPart.fromEncoded(path)); 1361 } 1362 1363 /** 1364 * Encodes the given segment and appends it to the path. 1365 */ 1366 public Builder appendPath(String newSegment) { 1367 return path(PathPart.appendDecodedSegment(path, newSegment)); 1368 } 1369 1370 /** 1371 * Appends the given segment to the path. 1372 */ 1373 public Builder appendEncodedPath(String newSegment) { 1374 return path(PathPart.appendEncodedSegment(path, newSegment)); 1375 } 1376 1377 Builder query(Part query) { 1378 // This URI will be hierarchical. 1379 this.opaquePart = null; 1380 1381 this.query = query; 1382 return this; 1383 } 1384 1385 /** 1386 * Encodes and sets the query. 1387 */ 1388 public Builder query(String query) { 1389 return query(Part.fromDecoded(query)); 1390 } 1391 1392 /** 1393 * Sets the previously encoded query. 1394 */ 1395 public Builder encodedQuery(String query) { 1396 return query(Part.fromEncoded(query)); 1397 } 1398 1399 Builder fragment(Part fragment) { 1400 this.fragment = fragment; 1401 return this; 1402 } 1403 1404 /** 1405 * Encodes and sets the fragment. 1406 */ 1407 public Builder fragment(String fragment) { 1408 return fragment(Part.fromDecoded(fragment)); 1409 } 1410 1411 /** 1412 * Sets the previously encoded fragment. 1413 */ 1414 public Builder encodedFragment(String fragment) { 1415 return fragment(Part.fromEncoded(fragment)); 1416 } 1417 1418 /** 1419 * Encodes the key and value and then appends the parameter to the 1420 * query string. 1421 * 1422 * @param key which will be encoded 1423 * @param value which will be encoded 1424 */ 1425 public Builder appendQueryParameter(String key, String value) { 1426 // This URI will be hierarchical. 1427 this.opaquePart = null; 1428 1429 String encodedParameter = encode(key, null) + "=" 1430 + encode(value, null); 1431 1432 if (query == null) { 1433 query = Part.fromEncoded(encodedParameter); 1434 return this; 1435 } 1436 1437 String oldQuery = query.getEncoded(); 1438 if (oldQuery == null || oldQuery.length() == 0) { 1439 query = Part.fromEncoded(encodedParameter); 1440 } else { 1441 query = Part.fromEncoded(oldQuery + "&" + encodedParameter); 1442 } 1443 1444 return this; 1445 } 1446 1447 /** 1448 * Constructs a Uri with the current attributes. 1449 * 1450 * @throws UnsupportedOperationException if the URI is opaque and the 1451 * scheme is null 1452 */ 1453 public Uri build() { 1454 if (opaquePart != null) { 1455 if (this.scheme == null) { 1456 throw new UnsupportedOperationException( 1457 "An opaque URI must have a scheme."); 1458 } 1459 1460 return new OpaqueUri(scheme, opaquePart, fragment); 1461 } else { 1462 // Hierarchical URIs should not return null for getPath(). 1463 PathPart path = this.path; 1464 if (path == null || path == PathPart.NULL) { 1465 path = PathPart.EMPTY; 1466 } else { 1467 // If we have a scheme and/or authority, the path must 1468 // be absolute. Prepend it with a '/' if necessary. 1469 if (hasSchemeOrAuthority()) { 1470 path = PathPart.makeAbsolute(path); 1471 } 1472 } 1473 1474 return new HierarchicalUri( 1475 scheme, authority, path, query, fragment); 1476 } 1477 } 1478 1479 private boolean hasSchemeOrAuthority() { 1480 return scheme != null 1481 || (authority != null && authority != Part.NULL); 1482 1483 } 1484 1485 @Override 1486 public String toString() { 1487 return build().toString(); 1488 } 1489 } 1490 1491 /** 1492 * Searches the query string for parameter values with the given key. 1493 * 1494 * @param key which will be encoded 1495 * 1496 * @throws UnsupportedOperationException if this isn't a hierarchical URI 1497 * @throws NullPointerException if key is null 1498 * 1499 * @return a list of decoded values 1500 */ 1501 public List<String> getQueryParameters(String key) { 1502 if (isOpaque()) { 1503 throw new UnsupportedOperationException(NOT_HIERARCHICAL); 1504 } 1505 1506 String query = getEncodedQuery(); 1507 if (query == null) { 1508 return Collections.emptyList(); 1509 } 1510 1511 String encodedKey; 1512 try { 1513 encodedKey = URLEncoder.encode(key, DEFAULT_ENCODING); 1514 } catch (UnsupportedEncodingException e) { 1515 throw new AssertionError(e); 1516 } 1517 1518 // Prepend query with "&" making the first parameter the same as the 1519 // rest. 1520 query = "&" + query; 1521 1522 // Parameter prefix. 1523 String prefix = "&" + encodedKey + "="; 1524 1525 ArrayList<String> values = new ArrayList<String>(); 1526 1527 int start = 0; 1528 int length = query.length(); 1529 while (start < length) { 1530 start = query.indexOf(prefix, start); 1531 1532 if (start == -1) { 1533 // No more values. 1534 break; 1535 } 1536 1537 // Move start to start of value. 1538 start += prefix.length(); 1539 1540 // Find end of value. 1541 int end = query.indexOf('&', start); 1542 if (end == -1) { 1543 end = query.length(); 1544 } 1545 1546 String value = query.substring(start, end); 1547 values.add(decode(value)); 1548 1549 start = end; 1550 } 1551 1552 return Collections.unmodifiableList(values); 1553 } 1554 1555 /** 1556 * Searches the query string for the first value with the given key. 1557 * 1558 * @param key which will be encoded 1559 * @throws UnsupportedOperationException if this isn't a hierarchical URI 1560 * @throws NullPointerException if key is null 1561 * 1562 * @return the decoded value or null if no parameter is found 1563 */ 1564 public String getQueryParameter(String key) { 1565 if (isOpaque()) { 1566 throw new UnsupportedOperationException(NOT_HIERARCHICAL); 1567 } 1568 1569 String query = getEncodedQuery(); 1570 1571 if (query == null) { 1572 return null; 1573 } 1574 1575 String encodedKey; 1576 try { 1577 encodedKey = URLEncoder.encode(key, DEFAULT_ENCODING); 1578 } catch (UnsupportedEncodingException e) { 1579 throw new AssertionError(e); 1580 } 1581 1582 String prefix = encodedKey + "="; 1583 1584 if (query.length() < prefix.length()) { 1585 return null; 1586 } 1587 1588 int start; 1589 if (query.startsWith(prefix)) { 1590 // It's the first parameter. 1591 start = prefix.length(); 1592 } else { 1593 // It must be later in the query string. 1594 prefix = "&" + prefix; 1595 start = query.indexOf(prefix); 1596 1597 if (start == -1) { 1598 // Not found. 1599 return null; 1600 } 1601 1602 start += prefix.length(); 1603 } 1604 1605 // Find end of value. 1606 int end = query.indexOf('&', start); 1607 if (end == -1) { 1608 end = query.length(); 1609 } 1610 1611 String value = query.substring(start, end); 1612 return decode(value); 1613 } 1614 1615 /** Identifies a null parcelled Uri. */ 1616 private static final int NULL_TYPE_ID = 0; 1617 1618 /** 1619 * Reads Uris from Parcels. 1620 */ 1621 public static final Parcelable.Creator<Uri> CREATOR 1622 = new Parcelable.Creator<Uri>() { 1623 public Uri createFromParcel(Parcel in) { 1624 int type = in.readInt(); 1625 switch (type) { 1626 case NULL_TYPE_ID: return null; 1627 case StringUri.TYPE_ID: return StringUri.readFrom(in); 1628 case OpaqueUri.TYPE_ID: return OpaqueUri.readFrom(in); 1629 case HierarchicalUri.TYPE_ID: 1630 return HierarchicalUri.readFrom(in); 1631 } 1632 1633 throw new AssertionError("Unknown URI type: " + type); 1634 } 1635 1636 public Uri[] newArray(int size) { 1637 return new Uri[size]; 1638 } 1639 }; 1640 1641 /** 1642 * Writes a Uri to a Parcel. 1643 * 1644 * @param out parcel to write to 1645 * @param uri to write, can be null 1646 */ 1647 public static void writeToParcel(Parcel out, Uri uri) { 1648 if (uri == null) { 1649 out.writeInt(NULL_TYPE_ID); 1650 } else { 1651 uri.writeToParcel(out, 0); 1652 } 1653 } 1654 1655 private static final char[] HEX_DIGITS = "0123456789ABCDEF".toCharArray(); 1656 1657 /** 1658 * Encodes characters in the given string as '%'-escaped octets 1659 * using the UTF-8 scheme. Leaves letters ("A-Z", "a-z"), numbers 1660 * ("0-9"), and unreserved characters ("_-!.~'()*") intact. Encodes 1661 * all other characters. 1662 * 1663 * @param s string to encode 1664 * @return an encoded version of s suitable for use as a URI component, 1665 * or null if s is null 1666 */ 1667 public static String encode(String s) { 1668 return encode(s, null); 1669 } 1670 1671 /** 1672 * Encodes characters in the given string as '%'-escaped octets 1673 * using the UTF-8 scheme. Leaves letters ("A-Z", "a-z"), numbers 1674 * ("0-9"), and unreserved characters ("_-!.~'()*") intact. Encodes 1675 * all other characters with the exception of those specified in the 1676 * allow argument. 1677 * 1678 * @param s string to encode 1679 * @param allow set of additional characters to allow in the encoded form, 1680 * null if no characters should be skipped 1681 * @return an encoded version of s suitable for use as a URI component, 1682 * or null if s is null 1683 */ 1684 public static String encode(String s, String allow) { 1685 if (s == null) { 1686 return null; 1687 } 1688 1689 // Lazily-initialized buffers. 1690 StringBuilder encoded = null; 1691 1692 int oldLength = s.length(); 1693 1694 // This loop alternates between copying over allowed characters and 1695 // encoding in chunks. This results in fewer method calls and 1696 // allocations than encoding one character at a time. 1697 int current = 0; 1698 while (current < oldLength) { 1699 // Start in "copying" mode where we copy over allowed chars. 1700 1701 // Find the next character which needs to be encoded. 1702 int nextToEncode = current; 1703 while (nextToEncode < oldLength 1704 && isAllowed(s.charAt(nextToEncode), allow)) { 1705 nextToEncode++; 1706 } 1707 1708 // If there's nothing more to encode... 1709 if (nextToEncode == oldLength) { 1710 if (current == 0) { 1711 // We didn't need to encode anything! 1712 return s; 1713 } else { 1714 // Presumably, we've already done some encoding. 1715 encoded.append(s, current, oldLength); 1716 return encoded.toString(); 1717 } 1718 } 1719 1720 if (encoded == null) { 1721 encoded = new StringBuilder(); 1722 } 1723 1724 if (nextToEncode > current) { 1725 // Append allowed characters leading up to this point. 1726 encoded.append(s, current, nextToEncode); 1727 } else { 1728 // assert nextToEncode == current 1729 } 1730 1731 // Switch to "encoding" mode. 1732 1733 // Find the next allowed character. 1734 current = nextToEncode; 1735 int nextAllowed = current + 1; 1736 while (nextAllowed < oldLength 1737 && !isAllowed(s.charAt(nextAllowed), allow)) { 1738 nextAllowed++; 1739 } 1740 1741 // Convert the substring to bytes and encode the bytes as 1742 // '%'-escaped octets. 1743 String toEncode = s.substring(current, nextAllowed); 1744 try { 1745 byte[] bytes = toEncode.getBytes(DEFAULT_ENCODING); 1746 int bytesLength = bytes.length; 1747 for (int i = 0; i < bytesLength; i++) { 1748 encoded.append('%'); 1749 encoded.append(HEX_DIGITS[(bytes[i] & 0xf0) >> 4]); 1750 encoded.append(HEX_DIGITS[bytes[i] & 0xf]); 1751 } 1752 } catch (UnsupportedEncodingException e) { 1753 throw new AssertionError(e); 1754 } 1755 1756 current = nextAllowed; 1757 } 1758 1759 // Encoded could still be null at this point if s is empty. 1760 return encoded == null ? s : encoded.toString(); 1761 } 1762 1763 /** 1764 * Returns true if the given character is allowed. 1765 * 1766 * @param c character to check 1767 * @param allow characters to allow 1768 * @return true if the character is allowed or false if it should be 1769 * encoded 1770 */ 1771 private static boolean isAllowed(char c, String allow) { 1772 return (c >= 'A' && c <= 'Z') 1773 || (c >= 'a' && c <= 'z') 1774 || (c >= '0' && c <= '9') 1775 || "_-!.~'()*".indexOf(c) != NOT_FOUND 1776 || (allow != null && allow.indexOf(c) != NOT_FOUND); 1777 } 1778 1779 /** Unicode replacement character: \\uFFFD. */ 1780 private static final byte[] REPLACEMENT = { (byte) 0xFF, (byte) 0xFD }; 1781 1782 /** 1783 * Decodes '%'-escaped octets in the given string using the UTF-8 scheme. 1784 * Replaces invalid octets with the unicode replacement character 1785 * ("\\uFFFD"). 1786 * 1787 * @param s encoded string to decode 1788 * @return the given string with escaped octets decoded, or null if 1789 * s is null 1790 */ 1791 public static String decode(String s) { 1792 /* 1793 Compared to java.net.URLEncoderDecoder.decode(), this method decodes a 1794 chunk at a time instead of one character at a time, and it doesn't 1795 throw exceptions. It also only allocates memory when necessary--if 1796 there's nothing to decode, this method won't do much. 1797 */ 1798 1799 if (s == null) { 1800 return null; 1801 } 1802 1803 // Lazily-initialized buffers. 1804 StringBuilder decoded = null; 1805 ByteArrayOutputStream out = null; 1806 1807 int oldLength = s.length(); 1808 1809 // This loop alternates between copying over normal characters and 1810 // escaping in chunks. This results in fewer method calls and 1811 // allocations than decoding one character at a time. 1812 int current = 0; 1813 while (current < oldLength) { 1814 // Start in "copying" mode where we copy over normal characters. 1815 1816 // Find the next escape sequence. 1817 int nextEscape = s.indexOf('%', current); 1818 1819 if (nextEscape == NOT_FOUND) { 1820 if (decoded == null) { 1821 // We didn't actually decode anything. 1822 return s; 1823 } else { 1824 // Append the remainder and return the decoded string. 1825 decoded.append(s, current, oldLength); 1826 return decoded.toString(); 1827 } 1828 } 1829 1830 // Prepare buffers. 1831 if (decoded == null) { 1832 // Looks like we're going to need the buffers... 1833 // We know the new string will be shorter. Using the old length 1834 // may overshoot a bit, but it will save us from resizing the 1835 // buffer. 1836 decoded = new StringBuilder(oldLength); 1837 out = new ByteArrayOutputStream(4); 1838 } else { 1839 // Clear decoding buffer. 1840 out.reset(); 1841 } 1842 1843 // Append characters leading up to the escape. 1844 if (nextEscape > current) { 1845 decoded.append(s, current, nextEscape); 1846 1847 current = nextEscape; 1848 } else { 1849 // assert current == nextEscape 1850 } 1851 1852 // Switch to "decoding" mode where we decode a string of escape 1853 // sequences. 1854 1855 // Decode and append escape sequences. Escape sequences look like 1856 // "%ab" where % is literal and a and b are hex digits. 1857 try { 1858 do { 1859 if (current + 2 >= oldLength) { 1860 // Truncated escape sequence. 1861 out.write(REPLACEMENT); 1862 } else { 1863 int a = Character.digit(s.charAt(current + 1), 16); 1864 int b = Character.digit(s.charAt(current + 2), 16); 1865 1866 if (a == -1 || b == -1) { 1867 // Non hex digits. 1868 out.write(REPLACEMENT); 1869 } else { 1870 // Combine the hex digits into one byte and write. 1871 out.write((a << 4) + b); 1872 } 1873 } 1874 1875 // Move passed the escape sequence. 1876 current += 3; 1877 } while (current < oldLength && s.charAt(current) == '%'); 1878 1879 // Decode UTF-8 bytes into a string and append it. 1880 decoded.append(out.toString(DEFAULT_ENCODING)); 1881 } catch (UnsupportedEncodingException e) { 1882 throw new AssertionError(e); 1883 } catch (IOException e) { 1884 throw new AssertionError(e); 1885 } 1886 } 1887 1888 // If we don't have a buffer, we didn't have to decode anything. 1889 return decoded == null ? s : decoded.toString(); 1890 } 1891 1892 /** 1893 * Support for part implementations. 1894 */ 1895 static abstract class AbstractPart { 1896 1897 /** 1898 * Enum which indicates which representation of a given part we have. 1899 */ 1900 static class Representation { 1901 static final int BOTH = 0; 1902 static final int ENCODED = 1; 1903 static final int DECODED = 2; 1904 } 1905 1906 volatile String encoded; 1907 volatile String decoded; 1908 1909 AbstractPart(String encoded, String decoded) { 1910 this.encoded = encoded; 1911 this.decoded = decoded; 1912 } 1913 1914 abstract String getEncoded(); 1915 1916 final String getDecoded() { 1917 @SuppressWarnings("StringEquality") 1918 boolean hasDecoded = decoded != NOT_CACHED; 1919 return hasDecoded ? decoded : (decoded = decode(encoded)); 1920 } 1921 1922 final void writeTo(Parcel parcel) { 1923 @SuppressWarnings("StringEquality") 1924 boolean hasEncoded = encoded != NOT_CACHED; 1925 1926 @SuppressWarnings("StringEquality") 1927 boolean hasDecoded = decoded != NOT_CACHED; 1928 1929 if (hasEncoded && hasDecoded) { 1930 parcel.writeInt(Representation.BOTH); 1931 parcel.writeString(encoded); 1932 parcel.writeString(decoded); 1933 } else if (hasEncoded) { 1934 parcel.writeInt(Representation.ENCODED); 1935 parcel.writeString(encoded); 1936 } else if (hasDecoded) { 1937 parcel.writeInt(Representation.DECODED); 1938 parcel.writeString(decoded); 1939 } else { 1940 throw new AssertionError(); 1941 } 1942 } 1943 } 1944 1945 /** 1946 * Immutable wrapper of encoded and decoded versions of a URI part. Lazily 1947 * creates the encoded or decoded version from the other. 1948 */ 1949 static class Part extends AbstractPart { 1950 1951 /** A part with null values. */ 1952 static final Part NULL = new EmptyPart(null); 1953 1954 /** A part with empty strings for values. */ 1955 static final Part EMPTY = new EmptyPart(""); 1956 1957 private Part(String encoded, String decoded) { 1958 super(encoded, decoded); 1959 } 1960 1961 boolean isEmpty() { 1962 return false; 1963 } 1964 1965 String getEncoded() { 1966 @SuppressWarnings("StringEquality") 1967 boolean hasEncoded = encoded != NOT_CACHED; 1968 return hasEncoded ? encoded : (encoded = encode(decoded)); 1969 } 1970 1971 static Part readFrom(Parcel parcel) { 1972 int representation = parcel.readInt(); 1973 switch (representation) { 1974 case Representation.BOTH: 1975 return from(parcel.readString(), parcel.readString()); 1976 case Representation.ENCODED: 1977 return fromEncoded(parcel.readString()); 1978 case Representation.DECODED: 1979 return fromDecoded(parcel.readString()); 1980 default: 1981 throw new AssertionError(); 1982 } 1983 } 1984 1985 /** 1986 * Returns given part or {@link #NULL} if the given part is null. 1987 */ 1988 static Part nonNull(Part part) { 1989 return part == null ? NULL : part; 1990 } 1991 1992 /** 1993 * Creates a part from the encoded string. 1994 * 1995 * @param encoded part string 1996 */ 1997 static Part fromEncoded(String encoded) { 1998 return from(encoded, NOT_CACHED); 1999 } 2000 2001 /** 2002 * Creates a part from the decoded string. 2003 * 2004 * @param decoded part string 2005 */ 2006 static Part fromDecoded(String decoded) { 2007 return from(NOT_CACHED, decoded); 2008 } 2009 2010 /** 2011 * Creates a part from the encoded and decoded strings. 2012 * 2013 * @param encoded part string 2014 * @param decoded part string 2015 */ 2016 static Part from(String encoded, String decoded) { 2017 // We have to check both encoded and decoded in case one is 2018 // NOT_CACHED. 2019 2020 if (encoded == null) { 2021 return NULL; 2022 } 2023 if (encoded.length() == 0) { 2024 return EMPTY; 2025 } 2026 2027 if (decoded == null) { 2028 return NULL; 2029 } 2030 if (decoded .length() == 0) { 2031 return EMPTY; 2032 } 2033 2034 return new Part(encoded, decoded); 2035 } 2036 2037 private static class EmptyPart extends Part { 2038 public EmptyPart(String value) { 2039 super(value, value); 2040 } 2041 2042 @Override 2043 boolean isEmpty() { 2044 return true; 2045 } 2046 } 2047 } 2048 2049 /** 2050 * Immutable wrapper of encoded and decoded versions of a path part. Lazily 2051 * creates the encoded or decoded version from the other. 2052 */ 2053 static class PathPart extends AbstractPart { 2054 2055 /** A part with null values. */ 2056 static final PathPart NULL = new PathPart(null, null); 2057 2058 /** A part with empty strings for values. */ 2059 static final PathPart EMPTY = new PathPart("", ""); 2060 2061 private PathPart(String encoded, String decoded) { 2062 super(encoded, decoded); 2063 } 2064 2065 String getEncoded() { 2066 @SuppressWarnings("StringEquality") 2067 boolean hasEncoded = encoded != NOT_CACHED; 2068 2069 // Don't encode '/'. 2070 return hasEncoded ? encoded : (encoded = encode(decoded, "/")); 2071 } 2072 2073 /** 2074 * Cached path segments. This doesn't need to be volatile--we don't 2075 * care if other threads see the result. 2076 */ 2077 private PathSegments pathSegments; 2078 2079 /** 2080 * Gets the individual path segments. Parses them if necessary. 2081 * 2082 * @return parsed path segments or null if this isn't a hierarchical 2083 * URI 2084 */ 2085 PathSegments getPathSegments() { 2086 if (pathSegments != null) { 2087 return pathSegments; 2088 } 2089 2090 String path = getEncoded(); 2091 if (path == null) { 2092 return pathSegments = PathSegments.EMPTY; 2093 } 2094 2095 PathSegmentsBuilder segmentBuilder = new PathSegmentsBuilder(); 2096 2097 int previous = 0; 2098 int current; 2099 while ((current = path.indexOf('/', previous)) > -1) { 2100 // This check keeps us from adding a segment if the path starts 2101 // '/' and an empty segment for "//". 2102 if (previous < current) { 2103 String decodedSegment 2104 = decode(path.substring(previous, current)); 2105 segmentBuilder.add(decodedSegment); 2106 } 2107 previous = current + 1; 2108 } 2109 2110 // Add in the final path segment. 2111 if (previous < path.length()) { 2112 segmentBuilder.add(decode(path.substring(previous))); 2113 } 2114 2115 return pathSegments = segmentBuilder.build(); 2116 } 2117 2118 static PathPart appendEncodedSegment(PathPart oldPart, 2119 String newSegment) { 2120 // If there is no old path, should we make the new path relative 2121 // or absolute? I pick absolute. 2122 2123 if (oldPart == null) { 2124 // No old path. 2125 return fromEncoded("/" + newSegment); 2126 } 2127 2128 String oldPath = oldPart.getEncoded(); 2129 2130 if (oldPath == null) { 2131 oldPath = ""; 2132 } 2133 2134 int oldPathLength = oldPath.length(); 2135 String newPath; 2136 if (oldPathLength == 0) { 2137 // No old path. 2138 newPath = "/" + newSegment; 2139 } else if (oldPath.charAt(oldPathLength - 1) == '/') { 2140 newPath = oldPath + newSegment; 2141 } else { 2142 newPath = oldPath + "/" + newSegment; 2143 } 2144 2145 return fromEncoded(newPath); 2146 } 2147 2148 static PathPart appendDecodedSegment(PathPart oldPart, String decoded) { 2149 String encoded = encode(decoded); 2150 2151 // TODO: Should we reuse old PathSegments? Probably not. 2152 return appendEncodedSegment(oldPart, encoded); 2153 } 2154 2155 static PathPart readFrom(Parcel parcel) { 2156 int representation = parcel.readInt(); 2157 switch (representation) { 2158 case Representation.BOTH: 2159 return from(parcel.readString(), parcel.readString()); 2160 case Representation.ENCODED: 2161 return fromEncoded(parcel.readString()); 2162 case Representation.DECODED: 2163 return fromDecoded(parcel.readString()); 2164 default: 2165 throw new AssertionError(); 2166 } 2167 } 2168 2169 /** 2170 * Creates a path from the encoded string. 2171 * 2172 * @param encoded part string 2173 */ 2174 static PathPart fromEncoded(String encoded) { 2175 return from(encoded, NOT_CACHED); 2176 } 2177 2178 /** 2179 * Creates a path from the decoded string. 2180 * 2181 * @param decoded part string 2182 */ 2183 static PathPart fromDecoded(String decoded) { 2184 return from(NOT_CACHED, decoded); 2185 } 2186 2187 /** 2188 * Creates a path from the encoded and decoded strings. 2189 * 2190 * @param encoded part string 2191 * @param decoded part string 2192 */ 2193 static PathPart from(String encoded, String decoded) { 2194 if (encoded == null) { 2195 return NULL; 2196 } 2197 2198 if (encoded.length() == 0) { 2199 return EMPTY; 2200 } 2201 2202 return new PathPart(encoded, decoded); 2203 } 2204 2205 /** 2206 * Prepends path values with "/" if they're present, not empty, and 2207 * they don't already start with "/". 2208 */ 2209 static PathPart makeAbsolute(PathPart oldPart) { 2210 @SuppressWarnings("StringEquality") 2211 boolean encodedCached = oldPart.encoded != NOT_CACHED; 2212 2213 // We don't care which version we use, and we don't want to force 2214 // unneccessary encoding/decoding. 2215 String oldPath = encodedCached ? oldPart.encoded : oldPart.decoded; 2216 2217 if (oldPath == null || oldPath.length() == 0 2218 || oldPath.startsWith("/")) { 2219 return oldPart; 2220 } 2221 2222 // Prepend encoded string if present. 2223 String newEncoded = encodedCached 2224 ? "/" + oldPart.encoded : NOT_CACHED; 2225 2226 // Prepend decoded string if present. 2227 @SuppressWarnings("StringEquality") 2228 boolean decodedCached = oldPart.decoded != NOT_CACHED; 2229 String newDecoded = decodedCached 2230 ? "/" + oldPart.decoded 2231 : NOT_CACHED; 2232 2233 return new PathPart(newEncoded, newDecoded); 2234 } 2235 } 2236 2237 /** 2238 * Creates a new Uri by appending an already-encoded path segment to a 2239 * base Uri. 2240 * 2241 * @param baseUri Uri to append path segment to 2242 * @param pathSegment encoded path segment to append 2243 * @return a new Uri based on baseUri with the given segment appended to 2244 * the path 2245 * @throws NullPointerException if baseUri is null 2246 */ 2247 public static Uri withAppendedPath(Uri baseUri, String pathSegment) { 2248 Builder builder = baseUri.buildUpon(); 2249 builder = builder.appendEncodedPath(pathSegment); 2250 return builder.build(); 2251 } 2252} 2253