Uri.java revision b8b8f044f4735b08f5a422637cfdcef43ac1a824
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 3296-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; 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 = authority; 1096 this.path = path; 1097 this.query = query; 1098 this.fragment = 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 if (authority != null) { 1162 String encodedAuthority = authority.getEncoded(); 1163 if (encodedAuthority != null) { 1164 // Even if the authority is "", we still want to append "//". 1165 builder.append("//").append(encodedAuthority); 1166 } 1167 } 1168 1169 // path is never null. 1170 String encodedPath = path.getEncoded(); 1171 if (encodedPath != null) { 1172 builder.append(encodedPath); 1173 } 1174 1175 if (query != null && !query.isEmpty()) { 1176 builder.append('?').append(query.getEncoded()); 1177 } 1178 } 1179 1180 public String getAuthority() { 1181 return this.authority.getDecoded(); 1182 } 1183 1184 public String getEncodedAuthority() { 1185 return this.authority.getEncoded(); 1186 } 1187 1188 public String getEncodedPath() { 1189 return this.path.getEncoded(); 1190 } 1191 1192 public String getPath() { 1193 return this.path.getDecoded(); 1194 } 1195 1196 public String getQuery() { 1197 return this.query.getDecoded(); 1198 } 1199 1200 public String getEncodedQuery() { 1201 return this.query.getEncoded(); 1202 } 1203 1204 public String getFragment() { 1205 return this.fragment.getDecoded(); 1206 } 1207 1208 public String getEncodedFragment() { 1209 return this.fragment.getEncoded(); 1210 } 1211 1212 public List<String> getPathSegments() { 1213 return this.path.getPathSegments(); 1214 } 1215 1216 private volatile String uriString = NOT_CACHED; 1217 1218 @Override 1219 public String toString() { 1220 @SuppressWarnings("StringEquality") 1221 boolean cached = (uriString != NOT_CACHED); 1222 return cached ? uriString 1223 : (uriString = makeUriString()); 1224 } 1225 1226 private String makeUriString() { 1227 StringBuilder builder = new StringBuilder(); 1228 1229 if (scheme != null) { 1230 builder.append(scheme).append(':'); 1231 } 1232 1233 appendSspTo(builder); 1234 1235 if (fragment != null && !fragment.isEmpty()) { 1236 builder.append('#').append(fragment.getEncoded()); 1237 } 1238 1239 return builder.toString(); 1240 } 1241 1242 public Builder buildUpon() { 1243 return new Builder() 1244 .scheme(scheme) 1245 .authority(authority) 1246 .path(path) 1247 .query(query) 1248 .fragment(fragment); 1249 } 1250 } 1251 1252 /** 1253 * Helper class for building or manipulating URI references. Not safe for 1254 * concurrent use. 1255 * 1256 * <p>An absolute hierarchical URI reference follows the pattern: 1257 * {@code <scheme>://<authority><absolute path>?<query>#<fragment>} 1258 * 1259 * <p>Relative URI references (which are always hierarchical) follow one 1260 * of two patterns: {@code <relative or absolute path>?<query>#<fragment>} 1261 * or {@code //<authority><absolute path>?<query>#<fragment>} 1262 * 1263 * <p>An opaque URI follows this pattern: 1264 * {@code <scheme>:<opaque part>#<fragment>} 1265 */ 1266 public static final class Builder { 1267 1268 private String scheme; 1269 private Part opaquePart; 1270 private Part authority; 1271 private PathPart path; 1272 private Part query; 1273 private Part fragment; 1274 1275 /** 1276 * Constructs a new Builder. 1277 */ 1278 public Builder() {} 1279 1280 /** 1281 * Sets the scheme. 1282 * 1283 * @param scheme name or {@code null} if this is a relative Uri 1284 */ 1285 public Builder scheme(String scheme) { 1286 this.scheme = scheme; 1287 return this; 1288 } 1289 1290 Builder opaquePart(Part opaquePart) { 1291 this.opaquePart = opaquePart; 1292 return this; 1293 } 1294 1295 /** 1296 * Encodes and sets the given opaque scheme-specific-part. 1297 * 1298 * @param opaquePart decoded opaque part 1299 */ 1300 public Builder opaquePart(String opaquePart) { 1301 return opaquePart(Part.fromDecoded(opaquePart)); 1302 } 1303 1304 /** 1305 * Sets the previously encoded opaque scheme-specific-part. 1306 * 1307 * @param opaquePart encoded opaque part 1308 */ 1309 public Builder encodedOpaquePart(String opaquePart) { 1310 return opaquePart(Part.fromEncoded(opaquePart)); 1311 } 1312 1313 Builder authority(Part authority) { 1314 // This URI will be hierarchical. 1315 this.opaquePart = null; 1316 1317 this.authority = authority; 1318 return this; 1319 } 1320 1321 /** 1322 * Encodes and sets the authority. 1323 */ 1324 public Builder authority(String authority) { 1325 return authority(Part.fromDecoded(authority)); 1326 } 1327 1328 /** 1329 * Sets the previously encoded authority. 1330 */ 1331 public Builder encodedAuthority(String authority) { 1332 return authority(Part.fromEncoded(authority)); 1333 } 1334 1335 Builder path(PathPart path) { 1336 // This URI will be hierarchical. 1337 this.opaquePart = null; 1338 1339 this.path = path; 1340 return this; 1341 } 1342 1343 /** 1344 * Sets the path. Leaves '/' characters intact but encodes others as 1345 * necessary. 1346 * 1347 * <p>If the path is not null and doesn't start with a '/', and if 1348 * you specify a scheme and/or authority, the builder will prepend the 1349 * given path with a '/'. 1350 */ 1351 public Builder path(String path) { 1352 return path(PathPart.fromDecoded(path)); 1353 } 1354 1355 /** 1356 * Sets the previously encoded path. 1357 * 1358 * <p>If the path is not null and doesn't start with a '/', and if 1359 * you specify a scheme and/or authority, the builder will prepend the 1360 * given path with a '/'. 1361 */ 1362 public Builder encodedPath(String path) { 1363 return path(PathPart.fromEncoded(path)); 1364 } 1365 1366 /** 1367 * Encodes the given segment and appends it to the path. 1368 */ 1369 public Builder appendPath(String newSegment) { 1370 return path(PathPart.appendDecodedSegment(path, newSegment)); 1371 } 1372 1373 /** 1374 * Appends the given segment to the path. 1375 */ 1376 public Builder appendEncodedPath(String newSegment) { 1377 return path(PathPart.appendEncodedSegment(path, newSegment)); 1378 } 1379 1380 Builder query(Part query) { 1381 // This URI will be hierarchical. 1382 this.opaquePart = null; 1383 1384 this.query = query; 1385 return this; 1386 } 1387 1388 /** 1389 * Encodes and sets the query. 1390 */ 1391 public Builder query(String query) { 1392 return query(Part.fromDecoded(query)); 1393 } 1394 1395 /** 1396 * Sets the previously encoded query. 1397 */ 1398 public Builder encodedQuery(String query) { 1399 return query(Part.fromEncoded(query)); 1400 } 1401 1402 Builder fragment(Part fragment) { 1403 this.fragment = fragment; 1404 return this; 1405 } 1406 1407 /** 1408 * Encodes and sets the fragment. 1409 */ 1410 public Builder fragment(String fragment) { 1411 return fragment(Part.fromDecoded(fragment)); 1412 } 1413 1414 /** 1415 * Sets the previously encoded fragment. 1416 */ 1417 public Builder encodedFragment(String fragment) { 1418 return fragment(Part.fromEncoded(fragment)); 1419 } 1420 1421 /** 1422 * Encodes the key and value and then appends the parameter to the 1423 * query string. 1424 * 1425 * @param key which will be encoded 1426 * @param value which will be encoded 1427 */ 1428 public Builder appendQueryParameter(String key, String value) { 1429 // This URI will be hierarchical. 1430 this.opaquePart = null; 1431 1432 String encodedParameter = encode(key, null) + "=" 1433 + encode(value, null); 1434 1435 if (query == null) { 1436 query = Part.fromEncoded(encodedParameter); 1437 return this; 1438 } 1439 1440 String oldQuery = query.getEncoded(); 1441 if (oldQuery == null || oldQuery.length() == 0) { 1442 query = Part.fromEncoded(encodedParameter); 1443 } else { 1444 query = Part.fromEncoded(oldQuery + "&" + encodedParameter); 1445 } 1446 1447 return this; 1448 } 1449 1450 /** 1451 * Constructs a Uri with the current attributes. 1452 * 1453 * @throws UnsupportedOperationException if the URI is opaque and the 1454 * scheme is null 1455 */ 1456 public Uri build() { 1457 if (opaquePart != null) { 1458 if (this.scheme == null) { 1459 throw new UnsupportedOperationException( 1460 "An opaque URI must have a scheme."); 1461 } 1462 1463 return new OpaqueUri(scheme, opaquePart, fragment); 1464 } else { 1465 // Hierarchical URIs should not return null for getPath(). 1466 PathPart path = this.path; 1467 if (path == null || path == PathPart.NULL) { 1468 path = PathPart.EMPTY; 1469 } else { 1470 // If we have a scheme and/or authority, the path must 1471 // be absolute. Prepend it with a '/' if necessary. 1472 if (hasSchemeOrAuthority()) { 1473 path = PathPart.makeAbsolute(path); 1474 } 1475 } 1476 1477 return new HierarchicalUri( 1478 scheme, authority, path, query, fragment); 1479 } 1480 } 1481 1482 private boolean hasSchemeOrAuthority() { 1483 return scheme != null 1484 || (authority != null && authority != Part.NULL); 1485 1486 } 1487 1488 @Override 1489 public String toString() { 1490 return build().toString(); 1491 } 1492 } 1493 1494 /** 1495 * Searches the query string for parameter values with the given key. 1496 * 1497 * @param key which will be encoded 1498 * 1499 * @throws UnsupportedOperationException if this isn't a hierarchical URI 1500 * @throws NullPointerException if key is null 1501 * 1502 * @return a list of decoded values 1503 */ 1504 public List<String> getQueryParameters(String key) { 1505 if (isOpaque()) { 1506 throw new UnsupportedOperationException(NOT_HIERARCHICAL); 1507 } 1508 1509 String query = getQuery(); 1510 if (query == null) { 1511 return Collections.emptyList(); 1512 } 1513 1514 String encodedKey; 1515 try { 1516 encodedKey = URLEncoder.encode(key, DEFAULT_ENCODING); 1517 } catch (UnsupportedEncodingException e) { 1518 throw new AssertionError(e); 1519 } 1520 1521 // Prepend query with "&" making the first parameter the same as the 1522 // rest. 1523 query = "&" + query; 1524 1525 // Parameter prefix. 1526 String prefix = "&" + encodedKey + "="; 1527 1528 ArrayList<String> values = new ArrayList<String>(); 1529 1530 int start = 0; 1531 int length = query.length(); 1532 while (start < length) { 1533 start = query.indexOf(prefix, start); 1534 1535 if (start == -1) { 1536 // No more values. 1537 break; 1538 } 1539 1540 // Move start to start of value. 1541 start += prefix.length(); 1542 1543 // Find end of value. 1544 int end = query.indexOf('&', start); 1545 if (end == -1) { 1546 end = query.length(); 1547 } 1548 1549 String value = query.substring(start, end); 1550 values.add(decode(value)); 1551 1552 start = end; 1553 } 1554 1555 return Collections.unmodifiableList(values); 1556 } 1557 1558 /** 1559 * Searches the query string for the first value with the given key. 1560 * 1561 * @param key which will be encoded 1562 * @throws UnsupportedOperationException if this isn't a hierarchical URI 1563 * @throws NullPointerException if key is null 1564 * 1565 * @return the decoded value or null if no parameter is found 1566 */ 1567 public String getQueryParameter(String key) { 1568 if (isOpaque()) { 1569 throw new UnsupportedOperationException(NOT_HIERARCHICAL); 1570 } 1571 1572 String query = getQuery(); 1573 1574 if (query == null) { 1575 return null; 1576 } 1577 1578 String encodedKey; 1579 try { 1580 encodedKey = URLEncoder.encode(key, DEFAULT_ENCODING); 1581 } catch (UnsupportedEncodingException e) { 1582 throw new AssertionError(e); 1583 } 1584 1585 String prefix = encodedKey + "="; 1586 1587 if (query.length() < prefix.length()) { 1588 return null; 1589 } 1590 1591 int start; 1592 if (query.startsWith(prefix)) { 1593 // It's the first parameter. 1594 start = prefix.length(); 1595 } else { 1596 // It must be later in the query string. 1597 prefix = "&" + prefix; 1598 start = query.indexOf(prefix); 1599 1600 if (start == -1) { 1601 // Not found. 1602 return null; 1603 } 1604 1605 start += prefix.length(); 1606 } 1607 1608 // Find end of value. 1609 int end = query.indexOf('&', start); 1610 if (end == -1) { 1611 end = query.length(); 1612 } 1613 1614 String value = query.substring(start, end); 1615 return decode(value); 1616 } 1617 1618 /** Identifies a null parcelled Uri. */ 1619 private static final int NULL_TYPE_ID = 0; 1620 1621 /** 1622 * Reads Uris from Parcels. 1623 */ 1624 public static final Parcelable.Creator<Uri> CREATOR 1625 = new Parcelable.Creator<Uri>() { 1626 public Uri createFromParcel(Parcel in) { 1627 int type = in.readInt(); 1628 switch (type) { 1629 case NULL_TYPE_ID: return null; 1630 case StringUri.TYPE_ID: return StringUri.readFrom(in); 1631 case OpaqueUri.TYPE_ID: return OpaqueUri.readFrom(in); 1632 case HierarchicalUri.TYPE_ID: 1633 return HierarchicalUri.readFrom(in); 1634 } 1635 1636 throw new AssertionError("Unknown URI type: " + type); 1637 } 1638 1639 public Uri[] newArray(int size) { 1640 return new Uri[size]; 1641 } 1642 }; 1643 1644 /** 1645 * Writes a Uri to a Parcel. 1646 * 1647 * @param out parcel to write to 1648 * @param uri to write, can be null 1649 */ 1650 public static void writeToParcel(Parcel out, Uri uri) { 1651 if (uri == null) { 1652 out.writeInt(NULL_TYPE_ID); 1653 } else { 1654 uri.writeToParcel(out, 0); 1655 } 1656 } 1657 1658 private static final char[] HEX_DIGITS = "0123456789ABCDEF".toCharArray(); 1659 1660 /** 1661 * Encodes characters in the given string as '%'-escaped octets 1662 * using the UTF-8 scheme. Leaves letters ("A-Z", "a-z"), numbers 1663 * ("0-9"), and unreserved characters ("_-!.~'()*") intact. Encodes 1664 * all other characters. 1665 * 1666 * @param s string to encode 1667 * @return an encoded version of s suitable for use as a URI component, 1668 * or null if s is null 1669 */ 1670 public static String encode(String s) { 1671 return encode(s, null); 1672 } 1673 1674 /** 1675 * Encodes characters in the given string as '%'-escaped octets 1676 * using the UTF-8 scheme. Leaves letters ("A-Z", "a-z"), numbers 1677 * ("0-9"), and unreserved characters ("_-!.~'()*") intact. Encodes 1678 * all other characters with the exception of those specified in the 1679 * allow argument. 1680 * 1681 * @param s string to encode 1682 * @param allow set of additional characters to allow in the encoded form, 1683 * null if no characters should be skipped 1684 * @return an encoded version of s suitable for use as a URI component, 1685 * or null if s is null 1686 */ 1687 public static String encode(String s, String allow) { 1688 if (s == null) { 1689 return null; 1690 } 1691 1692 // Lazily-initialized buffers. 1693 StringBuilder encoded = null; 1694 1695 int oldLength = s.length(); 1696 1697 // This loop alternates between copying over allowed characters and 1698 // encoding in chunks. This results in fewer method calls and 1699 // allocations than encoding one character at a time. 1700 int current = 0; 1701 while (current < oldLength) { 1702 // Start in "copying" mode where we copy over allowed chars. 1703 1704 // Find the next character which needs to be encoded. 1705 int nextToEncode = current; 1706 while (nextToEncode < oldLength 1707 && isAllowed(s.charAt(nextToEncode), allow)) { 1708 nextToEncode++; 1709 } 1710 1711 // If there's nothing more to encode... 1712 if (nextToEncode == oldLength) { 1713 if (current == 0) { 1714 // We didn't need to encode anything! 1715 return s; 1716 } else { 1717 // Presumably, we've already done some encoding. 1718 encoded.append(s, current, oldLength); 1719 return encoded.toString(); 1720 } 1721 } 1722 1723 if (encoded == null) { 1724 encoded = new StringBuilder(); 1725 } 1726 1727 if (nextToEncode > current) { 1728 // Append allowed characters leading up to this point. 1729 encoded.append(s, current, nextToEncode); 1730 } else { 1731 // assert nextToEncode == current 1732 } 1733 1734 // Switch to "encoding" mode. 1735 1736 // Find the next allowed character. 1737 current = nextToEncode; 1738 int nextAllowed = current + 1; 1739 while (nextAllowed < oldLength 1740 && !isAllowed(s.charAt(nextAllowed), allow)) { 1741 nextAllowed++; 1742 } 1743 1744 // Convert the substring to bytes and encode the bytes as 1745 // '%'-escaped octets. 1746 String toEncode = s.substring(current, nextAllowed); 1747 try { 1748 byte[] bytes = toEncode.getBytes(DEFAULT_ENCODING); 1749 int bytesLength = bytes.length; 1750 for (int i = 0; i < bytesLength; i++) { 1751 encoded.append('%'); 1752 encoded.append(HEX_DIGITS[(bytes[i] & 0xf0) >> 4]); 1753 encoded.append(HEX_DIGITS[bytes[i] & 0xf]); 1754 } 1755 } catch (UnsupportedEncodingException e) { 1756 throw new AssertionError(e); 1757 } 1758 1759 current = nextAllowed; 1760 } 1761 1762 // Encoded could still be null at this point if s is empty. 1763 return encoded == null ? s : encoded.toString(); 1764 } 1765 1766 /** 1767 * Returns true if the given character is allowed. 1768 * 1769 * @param c character to check 1770 * @param allow characters to allow 1771 * @return true if the character is allowed or false if it should be 1772 * encoded 1773 */ 1774 private static boolean isAllowed(char c, String allow) { 1775 return (c >= 'A' && c <= 'Z') 1776 || (c >= 'a' && c <= 'z') 1777 || (c >= '0' && c <= '9') 1778 || "_-!.~'()*".indexOf(c) != NOT_FOUND 1779 || (allow != null && allow.indexOf(c) != NOT_FOUND); 1780 } 1781 1782 /** Unicode replacement character: \\uFFFD. */ 1783 private static final byte[] REPLACEMENT = { (byte) 0xFF, (byte) 0xFD }; 1784 1785 /** 1786 * Decodes '%'-escaped octets in the given string using the UTF-8 scheme. 1787 * Replaces invalid octets with the unicode replacement character 1788 * ("\\uFFFD"). 1789 * 1790 * @param s encoded string to decode 1791 * @return the given string with escaped octets decoded, or null if 1792 * s is null 1793 */ 1794 public static String decode(String s) { 1795 /* 1796 Compared to java.net.URLEncoderDecoder.decode(), this method decodes a 1797 chunk at a time instead of one character at a time, and it doesn't 1798 throw exceptions. It also only allocates memory when necessary--if 1799 there's nothing to decode, this method won't do much. 1800 */ 1801 1802 if (s == null) { 1803 return null; 1804 } 1805 1806 // Lazily-initialized buffers. 1807 StringBuilder decoded = null; 1808 ByteArrayOutputStream out = null; 1809 1810 int oldLength = s.length(); 1811 1812 // This loop alternates between copying over normal characters and 1813 // escaping in chunks. This results in fewer method calls and 1814 // allocations than decoding one character at a time. 1815 int current = 0; 1816 while (current < oldLength) { 1817 // Start in "copying" mode where we copy over normal characters. 1818 1819 // Find the next escape sequence. 1820 int nextEscape = s.indexOf('%', current); 1821 1822 if (nextEscape == NOT_FOUND) { 1823 if (decoded == null) { 1824 // We didn't actually decode anything. 1825 return s; 1826 } else { 1827 // Append the remainder and return the decoded string. 1828 decoded.append(s, current, oldLength); 1829 return decoded.toString(); 1830 } 1831 } 1832 1833 // Prepare buffers. 1834 if (decoded == null) { 1835 // Looks like we're going to need the buffers... 1836 // We know the new string will be shorter. Using the old length 1837 // may overshoot a bit, but it will save us from resizing the 1838 // buffer. 1839 decoded = new StringBuilder(oldLength); 1840 out = new ByteArrayOutputStream(4); 1841 } else { 1842 // Clear decoding buffer. 1843 out.reset(); 1844 } 1845 1846 // Append characters leading up to the escape. 1847 if (nextEscape > current) { 1848 decoded.append(s, current, nextEscape); 1849 1850 current = nextEscape; 1851 } else { 1852 // assert current == nextEscape 1853 } 1854 1855 // Switch to "decoding" mode where we decode a string of escape 1856 // sequences. 1857 1858 // Decode and append escape sequences. Escape sequences look like 1859 // "%ab" where % is literal and a and b are hex digits. 1860 try { 1861 do { 1862 if (current + 2 >= oldLength) { 1863 // Truncated escape sequence. 1864 out.write(REPLACEMENT); 1865 } else { 1866 int a = Character.digit(s.charAt(current + 1), 16); 1867 int b = Character.digit(s.charAt(current + 2), 16); 1868 1869 if (a == -1 || b == -1) { 1870 // Non hex digits. 1871 out.write(REPLACEMENT); 1872 } else { 1873 // Combine the hex digits into one byte and write. 1874 out.write((a << 4) + b); 1875 } 1876 } 1877 1878 // Move passed the escape sequence. 1879 current += 3; 1880 } while (current < oldLength && s.charAt(current) == '%'); 1881 1882 // Decode UTF-8 bytes into a string and append it. 1883 decoded.append(out.toString(DEFAULT_ENCODING)); 1884 } catch (UnsupportedEncodingException e) { 1885 throw new AssertionError(e); 1886 } catch (IOException e) { 1887 throw new AssertionError(e); 1888 } 1889 } 1890 1891 // If we don't have a buffer, we didn't have to decode anything. 1892 return decoded == null ? s : decoded.toString(); 1893 } 1894 1895 /** 1896 * Support for part implementations. 1897 */ 1898 static abstract class AbstractPart { 1899 1900 /** 1901 * Enum which indicates which representation of a given part we have. 1902 */ 1903 static class Representation { 1904 static final int BOTH = 0; 1905 static final int ENCODED = 1; 1906 static final int DECODED = 2; 1907 } 1908 1909 volatile String encoded; 1910 volatile String decoded; 1911 1912 AbstractPart(String encoded, String decoded) { 1913 this.encoded = encoded; 1914 this.decoded = decoded; 1915 } 1916 1917 abstract String getEncoded(); 1918 1919 final String getDecoded() { 1920 @SuppressWarnings("StringEquality") 1921 boolean hasDecoded = decoded != NOT_CACHED; 1922 return hasDecoded ? decoded : (decoded = decode(encoded)); 1923 } 1924 1925 final void writeTo(Parcel parcel) { 1926 @SuppressWarnings("StringEquality") 1927 boolean hasEncoded = encoded != NOT_CACHED; 1928 1929 @SuppressWarnings("StringEquality") 1930 boolean hasDecoded = decoded != NOT_CACHED; 1931 1932 if (hasEncoded && hasDecoded) { 1933 parcel.writeInt(Representation.BOTH); 1934 parcel.writeString(encoded); 1935 parcel.writeString(decoded); 1936 } else if (hasEncoded) { 1937 parcel.writeInt(Representation.ENCODED); 1938 parcel.writeString(encoded); 1939 } else if (hasDecoded) { 1940 parcel.writeInt(Representation.DECODED); 1941 parcel.writeString(decoded); 1942 } else { 1943 throw new AssertionError(); 1944 } 1945 } 1946 } 1947 1948 /** 1949 * Immutable wrapper of encoded and decoded versions of a URI part. Lazily 1950 * creates the encoded or decoded version from the other. 1951 */ 1952 static class Part extends AbstractPart { 1953 1954 /** A part with null values. */ 1955 static final Part NULL = new EmptyPart(null); 1956 1957 /** A part with empty strings for values. */ 1958 static final Part EMPTY = new EmptyPart(""); 1959 1960 private Part(String encoded, String decoded) { 1961 super(encoded, decoded); 1962 } 1963 1964 boolean isEmpty() { 1965 return false; 1966 } 1967 1968 String getEncoded() { 1969 @SuppressWarnings("StringEquality") 1970 boolean hasEncoded = encoded != NOT_CACHED; 1971 return hasEncoded ? encoded : (encoded = encode(decoded)); 1972 } 1973 1974 static Part readFrom(Parcel parcel) { 1975 int representation = parcel.readInt(); 1976 switch (representation) { 1977 case Representation.BOTH: 1978 return from(parcel.readString(), parcel.readString()); 1979 case Representation.ENCODED: 1980 return fromEncoded(parcel.readString()); 1981 case Representation.DECODED: 1982 return fromDecoded(parcel.readString()); 1983 default: 1984 throw new AssertionError(); 1985 } 1986 } 1987 1988 /** 1989 * Returns given part or {@link #NULL} if the given part is null. 1990 */ 1991 static Part nonNull(Part part) { 1992 return part == null ? NULL : part; 1993 } 1994 1995 /** 1996 * Creates a part from the encoded string. 1997 * 1998 * @param encoded part string 1999 */ 2000 static Part fromEncoded(String encoded) { 2001 return from(encoded, NOT_CACHED); 2002 } 2003 2004 /** 2005 * Creates a part from the decoded string. 2006 * 2007 * @param decoded part string 2008 */ 2009 static Part fromDecoded(String decoded) { 2010 return from(NOT_CACHED, decoded); 2011 } 2012 2013 /** 2014 * Creates a part from the encoded and decoded strings. 2015 * 2016 * @param encoded part string 2017 * @param decoded part string 2018 */ 2019 static Part from(String encoded, String decoded) { 2020 // We have to check both encoded and decoded in case one is 2021 // NOT_CACHED. 2022 2023 if (encoded == null) { 2024 return NULL; 2025 } 2026 if (encoded.length() == 0) { 2027 return EMPTY; 2028 } 2029 2030 if (decoded == null) { 2031 return NULL; 2032 } 2033 if (decoded .length() == 0) { 2034 return EMPTY; 2035 } 2036 2037 return new Part(encoded, decoded); 2038 } 2039 2040 private static class EmptyPart extends Part { 2041 public EmptyPart(String value) { 2042 super(value, value); 2043 } 2044 2045 @Override 2046 boolean isEmpty() { 2047 return true; 2048 } 2049 } 2050 } 2051 2052 /** 2053 * Immutable wrapper of encoded and decoded versions of a path part. Lazily 2054 * creates the encoded or decoded version from the other. 2055 */ 2056 static class PathPart extends AbstractPart { 2057 2058 /** A part with null values. */ 2059 static final PathPart NULL = new PathPart(null, null); 2060 2061 /** A part with empty strings for values. */ 2062 static final PathPart EMPTY = new PathPart("", ""); 2063 2064 private PathPart(String encoded, String decoded) { 2065 super(encoded, decoded); 2066 } 2067 2068 String getEncoded() { 2069 @SuppressWarnings("StringEquality") 2070 boolean hasEncoded = encoded != NOT_CACHED; 2071 2072 // Don't encode '/'. 2073 return hasEncoded ? encoded : (encoded = encode(decoded, "/")); 2074 } 2075 2076 /** 2077 * Cached path segments. This doesn't need to be volatile--we don't 2078 * care if other threads see the result. 2079 */ 2080 private PathSegments pathSegments; 2081 2082 /** 2083 * Gets the individual path segments. Parses them if necessary. 2084 * 2085 * @return parsed path segments or null if this isn't a hierarchical 2086 * URI 2087 */ 2088 PathSegments getPathSegments() { 2089 if (pathSegments != null) { 2090 return pathSegments; 2091 } 2092 2093 String path = getEncoded(); 2094 if (path == null) { 2095 return pathSegments = PathSegments.EMPTY; 2096 } 2097 2098 PathSegmentsBuilder segmentBuilder = new PathSegmentsBuilder(); 2099 2100 int previous = 0; 2101 int current; 2102 while ((current = path.indexOf('/', previous)) > -1) { 2103 // This check keeps us from adding a segment if the path starts 2104 // '/' and an empty segment for "//". 2105 if (previous < current) { 2106 String decodedSegment 2107 = decode(path.substring(previous, current)); 2108 segmentBuilder.add(decodedSegment); 2109 } 2110 previous = current + 1; 2111 } 2112 2113 // Add in the final path segment. 2114 if (previous < path.length()) { 2115 segmentBuilder.add(decode(path.substring(previous))); 2116 } 2117 2118 return pathSegments = segmentBuilder.build(); 2119 } 2120 2121 static PathPart appendEncodedSegment(PathPart oldPart, 2122 String newSegment) { 2123 // If there is no old path, should we make the new path relative 2124 // or absolute? I pick absolute. 2125 2126 if (oldPart == null) { 2127 // No old path. 2128 return fromEncoded("/" + newSegment); 2129 } 2130 2131 String oldPath = oldPart.getEncoded(); 2132 2133 if (oldPath == null) { 2134 oldPath = ""; 2135 } 2136 2137 int oldPathLength = oldPath.length(); 2138 String newPath; 2139 if (oldPathLength == 0) { 2140 // No old path. 2141 newPath = "/" + newSegment; 2142 } else if (oldPath.charAt(oldPathLength - 1) == '/') { 2143 newPath = oldPath + newSegment; 2144 } else { 2145 newPath = oldPath + "/" + newSegment; 2146 } 2147 2148 return fromEncoded(newPath); 2149 } 2150 2151 static PathPart appendDecodedSegment(PathPart oldPart, String decoded) { 2152 String encoded = encode(decoded); 2153 2154 // TODO: Should we reuse old PathSegments? Probably not. 2155 return appendEncodedSegment(oldPart, encoded); 2156 } 2157 2158 static PathPart readFrom(Parcel parcel) { 2159 int representation = parcel.readInt(); 2160 switch (representation) { 2161 case Representation.BOTH: 2162 return from(parcel.readString(), parcel.readString()); 2163 case Representation.ENCODED: 2164 return fromEncoded(parcel.readString()); 2165 case Representation.DECODED: 2166 return fromDecoded(parcel.readString()); 2167 default: 2168 throw new AssertionError(); 2169 } 2170 } 2171 2172 /** 2173 * Creates a path from the encoded string. 2174 * 2175 * @param encoded part string 2176 */ 2177 static PathPart fromEncoded(String encoded) { 2178 return from(encoded, NOT_CACHED); 2179 } 2180 2181 /** 2182 * Creates a path from the decoded string. 2183 * 2184 * @param decoded part string 2185 */ 2186 static PathPart fromDecoded(String decoded) { 2187 return from(NOT_CACHED, decoded); 2188 } 2189 2190 /** 2191 * Creates a path from the encoded and decoded strings. 2192 * 2193 * @param encoded part string 2194 * @param decoded part string 2195 */ 2196 static PathPart from(String encoded, String decoded) { 2197 if (encoded == null) { 2198 return NULL; 2199 } 2200 2201 if (encoded.length() == 0) { 2202 return EMPTY; 2203 } 2204 2205 return new PathPart(encoded, decoded); 2206 } 2207 2208 /** 2209 * Prepends path values with "/" if they're present, not empty, and 2210 * they don't already start with "/". 2211 */ 2212 static PathPart makeAbsolute(PathPart oldPart) { 2213 @SuppressWarnings("StringEquality") 2214 boolean encodedCached = oldPart.encoded != NOT_CACHED; 2215 2216 // We don't care which version we use, and we don't want to force 2217 // unneccessary encoding/decoding. 2218 String oldPath = encodedCached ? oldPart.encoded : oldPart.decoded; 2219 2220 if (oldPath == null || oldPath.length() == 0 2221 || oldPath.startsWith("/")) { 2222 return oldPart; 2223 } 2224 2225 // Prepend encoded string if present. 2226 String newEncoded = encodedCached 2227 ? "/" + oldPart.encoded : NOT_CACHED; 2228 2229 // Prepend decoded string if present. 2230 @SuppressWarnings("StringEquality") 2231 boolean decodedCached = oldPart.decoded != NOT_CACHED; 2232 String newDecoded = decodedCached 2233 ? "/" + oldPart.decoded 2234 : NOT_CACHED; 2235 2236 return new PathPart(newEncoded, newDecoded); 2237 } 2238 } 2239 2240 /** 2241 * Creates a new Uri by appending an already-encoded path segment to a 2242 * base Uri. 2243 * 2244 * @param baseUri Uri to append path segment to 2245 * @param pathSegment encoded path segment to append 2246 * @return a new Uri based on baseUri with the given segment appended to 2247 * the path 2248 * @throws NullPointerException if baseUri is null 2249 */ 2250 public static Uri withAppendedPath(Uri baseUri, String pathSegment) { 2251 Builder builder = baseUri.buildUpon(); 2252 builder = builder.appendEncodedPath(pathSegment); 2253 return builder.build(); 2254 } 2255} 2256