001/* 002 * Copyright (C) 2011 The Guava Authors 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package com.google.common.net; 018 019import static com.google.common.base.CharMatcher.ASCII; 020import static com.google.common.base.CharMatcher.JAVA_ISO_CONTROL; 021import static com.google.common.base.Charsets.UTF_8; 022import static com.google.common.base.Preconditions.checkArgument; 023import static com.google.common.base.Preconditions.checkNotNull; 024import static com.google.common.base.Preconditions.checkState; 025 026import com.google.common.annotations.Beta; 027import com.google.common.annotations.GwtCompatible; 028import com.google.common.base.Ascii; 029import com.google.common.base.CharMatcher; 030import com.google.common.base.Function; 031import com.google.common.base.Joiner; 032import com.google.common.base.Joiner.MapJoiner; 033import com.google.common.base.Objects; 034import com.google.common.base.Optional; 035import com.google.common.collect.ImmutableListMultimap; 036import com.google.common.collect.ImmutableMultiset; 037import com.google.common.collect.ImmutableSet; 038import com.google.common.collect.Iterables; 039import com.google.common.collect.Maps; 040import com.google.common.collect.Multimap; 041import com.google.common.collect.Multimaps; 042 043import java.nio.charset.Charset; 044import java.nio.charset.IllegalCharsetNameException; 045import java.nio.charset.UnsupportedCharsetException; 046import java.util.Collection; 047import java.util.Map; 048import java.util.Map.Entry; 049 050import javax.annotation.Nullable; 051import javax.annotation.concurrent.Immutable; 052 053/** 054 * Represents an <a href="http://en.wikipedia.org/wiki/Internet_media_type">Internet Media Type</a> 055 * (also known as a MIME Type or Content Type). This class also supports the concept of media ranges 056 * <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.1">defined by HTTP/1.1</a>. 057 * As such, the {@code *} character is treated as a wildcard and is used to represent any acceptable 058 * type or subtype value. A media type may not have wildcard type with a declared subtype. The 059 * {@code *} character has no special meaning as part of a parameter. All values for type, subtype, 060 * parameter attributes or parameter values must be valid according to RFCs 061 * <a href="http://www.ietf.org/rfc/rfc2045.txt">2045</a> and 062 * <a href="http://www.ietf.org/rfc/rfc2046.txt">2046</a>. 063 * 064 * <p>All portions of the media type that are case-insensitive (type, subtype, parameter attributes) 065 * are normalized to lowercase. The value of the {@code charset} parameter is normalized to 066 * lowercase, but all others are left as-is. 067 * 068 * <p>Note that this specifically does <strong>not</strong> represent the value of the MIME 069 * {@code Content-Type} header and as such has no support for header-specific considerations such as 070 * line folding and comments. 071 * 072 * <p>For media types that take a charset the predefined constants default to UTF-8 and have a 073 * "_UTF_8" suffix. To get a version without a character set, use {@link #withoutParameters}. 074 * 075 * @since 12.0 076 * 077 * @author Gregory Kick 078 */ 079@Beta 080@GwtCompatible 081@Immutable 082public final class MediaType { 083 private static final String CHARSET_ATTRIBUTE = "charset"; 084 private static final ImmutableListMultimap<String, String> UTF_8_CONSTANT_PARAMETERS = 085 ImmutableListMultimap.of(CHARSET_ATTRIBUTE, Ascii.toLowerCase(UTF_8.name())); 086 087 /** Matcher for type, subtype and attributes. */ 088 private static final CharMatcher TOKEN_MATCHER = ASCII.and(JAVA_ISO_CONTROL.negate()) 089 .and(CharMatcher.isNot(' ')) 090 .and(CharMatcher.noneOf("()<>@,;:\\\"/[]?=")); 091 private static final CharMatcher QUOTED_TEXT_MATCHER = ASCII 092 .and(CharMatcher.noneOf("\"\\\r")); 093 /* 094 * This matches the same characters as linear-white-space from RFC 822, but we make no effort to 095 * enforce any particular rules with regards to line folding as stated in the class docs. 096 */ 097 private static final CharMatcher LINEAR_WHITE_SPACE = CharMatcher.anyOf(" \t\r\n"); 098 099 // TODO(gak): make these public? 100 private static final String APPLICATION_TYPE = "application"; 101 private static final String AUDIO_TYPE = "audio"; 102 private static final String IMAGE_TYPE = "image"; 103 private static final String TEXT_TYPE = "text"; 104 private static final String VIDEO_TYPE = "video"; 105 106 private static final String WILDCARD = "*"; 107 108 private static final Map<MediaType, MediaType> KNOWN_TYPES = Maps.newHashMap(); 109 110 private static MediaType createConstant(String type, String subtype) { 111 return addKnownType(new MediaType(type, subtype, ImmutableListMultimap.<String, String>of())); 112 } 113 114 private static MediaType createConstantUtf8(String type, String subtype) { 115 return addKnownType(new MediaType(type, subtype, UTF_8_CONSTANT_PARAMETERS)); 116 } 117 118 private static MediaType addKnownType(MediaType mediaType) { 119 KNOWN_TYPES.put(mediaType, mediaType); 120 return mediaType; 121 } 122 123 /* 124 * The following constants are grouped by their type and ordered alphabetically by the constant 125 * name within that type. The constant name should be a sensible identifier that is closest to the 126 * "common name" of the media. This is often, but not necessarily the same as the subtype. 127 * 128 * Be sure to declare all constants with the type and subtype in all lowercase. For types that 129 * take a charset (e.g. all text/* types), default to UTF-8 and suffix the constant name with 130 * "_UTF_8". 131 */ 132 133 public static final MediaType ANY_TYPE = createConstant(WILDCARD, WILDCARD); 134 public static final MediaType ANY_TEXT_TYPE = createConstant(TEXT_TYPE, WILDCARD); 135 public static final MediaType ANY_IMAGE_TYPE = createConstant(IMAGE_TYPE, WILDCARD); 136 public static final MediaType ANY_AUDIO_TYPE = createConstant(AUDIO_TYPE, WILDCARD); 137 public static final MediaType ANY_VIDEO_TYPE = createConstant(VIDEO_TYPE, WILDCARD); 138 public static final MediaType ANY_APPLICATION_TYPE = createConstant(APPLICATION_TYPE, WILDCARD); 139 140 /* text types */ 141 public static final MediaType CACHE_MANIFEST_UTF_8 = 142 createConstantUtf8(TEXT_TYPE, "cache-manifest"); 143 public static final MediaType CSS_UTF_8 = createConstantUtf8(TEXT_TYPE, "css"); 144 public static final MediaType CSV_UTF_8 = createConstantUtf8(TEXT_TYPE, "csv"); 145 public static final MediaType HTML_UTF_8 = createConstantUtf8(TEXT_TYPE, "html"); 146 public static final MediaType I_CALENDAR_UTF_8 = createConstantUtf8(TEXT_TYPE, "calendar"); 147 public static final MediaType PLAIN_TEXT_UTF_8 = createConstantUtf8(TEXT_TYPE, "plain"); 148 /** 149 * <a href="http://www.rfc-editor.org/rfc/rfc4329.txt">RFC 4329</a> declares 150 * {@link #JAVASCRIPT_UTF_8 application/javascript} to be the correct media type for JavaScript, 151 * but this may be necessary in certain situations for compatibility. 152 */ 153 public static final MediaType TEXT_JAVASCRIPT_UTF_8 = createConstantUtf8(TEXT_TYPE, "javascript"); 154 /** 155 * <a href="http://www.iana.org/assignments/media-types/text/tab-separated-values"> 156 * Tab separated values</a>. 157 * 158 * @since 15.0 159 */ 160 public static final MediaType TSV_UTF_8 = createConstantUtf8(TEXT_TYPE, "tab-separated-values"); 161 public static final MediaType VCARD_UTF_8 = createConstantUtf8(TEXT_TYPE, "vcard"); 162 public static final MediaType WML_UTF_8 = createConstantUtf8(TEXT_TYPE, "vnd.wap.wml"); 163 /** 164 * As described in <a href="http://www.ietf.org/rfc/rfc3023.txt">RFC 3023</a>, this constant 165 * ({@code text/xml}) is used for XML documents that are "readable by casual users." 166 * {@link #APPLICATION_XML_UTF_8} is provided for documents that are intended for applications. 167 */ 168 public static final MediaType XML_UTF_8 = createConstantUtf8(TEXT_TYPE, "xml"); 169 170 /* image types */ 171 public static final MediaType BMP = createConstant(IMAGE_TYPE, "bmp"); 172 /** 173 * The media type for the <a href="http://en.wikipedia.org/wiki/Camera_Image_File_Format">Canon 174 * Image File Format</a> ({@code crw} files), a widely-used "raw image" format for cameras. It is 175 * found in {@code /etc/mime.types}, e.g. in <href= 176 * "http://anonscm.debian.org/gitweb/?p=collab-maint/mime-support.git;a=blob;f=mime.types;hb=HEAD" 177 * >Debian 3.48-1</a>. 178 * 179 * @since 15.0 180 */ 181 public static final MediaType CRW = createConstant(IMAGE_TYPE, "x-canon-crw"); 182 public static final MediaType GIF = createConstant(IMAGE_TYPE, "gif"); 183 public static final MediaType ICO = createConstant(IMAGE_TYPE, "vnd.microsoft.icon"); 184 public static final MediaType JPEG = createConstant(IMAGE_TYPE, "jpeg"); 185 public static final MediaType PNG = createConstant(IMAGE_TYPE, "png"); 186 /** 187 * The media type for the Photoshop File Format ({@code psd} files) as defined by <a href= 188 * "http://www.iana.org/assignments/media-types/image/vnd.adobe.photoshop">IANA</a>, and found in 189 * {@code /etc/mime.types}, e.g. <a href= 190 * "http://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x/conf/mime.types"></a> of the Apache 191 * <a href="http://httpd.apache.org/">HTTPD project</a>; for the specification, see 192 * <href="http://www.adobe.com/devnet-apps/photoshop/fileformatashtml/PhotoshopFileFormats.htm"> 193 * Adobe Photoshop Document Format</a> and <a href= 194 * "http://en.wikipedia.org/wiki/Adobe_Photoshop#File_format">Wikipedia</a>; this is the regular 195 * output/input of Photoshop (which can also export to various image formats; note that files with 196 * extension "PSB" are in a distinct but related format). 197 * <p>This is a more recent replacement for the older, experimental type 198 * {@code x-photoshop}: <a href="http://tools.ietf.org/html/rfc2046#section-6">RFC-2046.6</a>. 199 * 200 * @since 15.0 201 */ 202 public static final MediaType PSD = createConstant(IMAGE_TYPE, "vnd.adobe.photoshop"); 203 public static final MediaType SVG_UTF_8 = createConstantUtf8(IMAGE_TYPE, "svg+xml"); 204 public static final MediaType TIFF = createConstant(IMAGE_TYPE, "tiff"); 205 public static final MediaType WEBP = createConstant(IMAGE_TYPE, "webp"); 206 207 /* audio types */ 208 public static final MediaType MP4_AUDIO = createConstant(AUDIO_TYPE, "mp4"); 209 public static final MediaType MPEG_AUDIO = createConstant(AUDIO_TYPE, "mpeg"); 210 public static final MediaType OGG_AUDIO = createConstant(AUDIO_TYPE, "ogg"); 211 public static final MediaType WEBM_AUDIO = createConstant(AUDIO_TYPE, "webm"); 212 213 /* video types */ 214 public static final MediaType MP4_VIDEO = createConstant(VIDEO_TYPE, "mp4"); 215 public static final MediaType MPEG_VIDEO = createConstant(VIDEO_TYPE, "mpeg"); 216 public static final MediaType OGG_VIDEO = createConstant(VIDEO_TYPE, "ogg"); 217 public static final MediaType QUICKTIME = createConstant(VIDEO_TYPE, "quicktime"); 218 public static final MediaType WEBM_VIDEO = createConstant(VIDEO_TYPE, "webm"); 219 public static final MediaType WMV = createConstant(VIDEO_TYPE, "x-ms-wmv"); 220 221 /* application types */ 222 /** 223 * As described in <a href="http://www.ietf.org/rfc/rfc3023.txt">RFC 3023</a>, this constant 224 * ({@code application/xml}) is used for XML documents that are "unreadable by casual users." 225 * {@link #XML_UTF_8} is provided for documents that may be read by users. 226 */ 227 public static final MediaType APPLICATION_XML_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "xml"); 228 public static final MediaType ATOM_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "atom+xml"); 229 public static final MediaType BZIP2 = createConstant(APPLICATION_TYPE, "x-bzip2"); 230 /** 231 * Media type for <a href="http://en.wikipedia.org/wiki/Embedded_OpenType">Embedded OpenType</a> 232 * fonts. This is 233 * <a href="http://www.iana.org/assignments/media-types/application/vnd.ms-fontobject">registered 234 * </a> with the IANA. 235 * 236 * @since 17.0 237 */ 238 public static final MediaType EOT = createConstant(APPLICATION_TYPE, "vnd.ms-fontobject"); 239 /** 240 * As described in the <a href="http://idpf.org/epub">International Digital Publishing Forum</a> 241 * EPUB is the distribution and interchange format standard for digital publications and 242 * documents. This media type is defined in the 243 * <a href="http://www.idpf.org/epub/30/spec/epub30-ocf.html">EPUB Open Container Format</a> 244 * specification. 245 * 246 * @since 15.0 247 */ 248 public static final MediaType EPUB = createConstant(APPLICATION_TYPE, "epub+zip"); 249 public static final MediaType FORM_DATA = createConstant(APPLICATION_TYPE, 250 "x-www-form-urlencoded"); 251 /** 252 * As described in <a href="https://www.rsa.com/rsalabs/node.asp?id=2138">PKCS #12: Personal 253 * Information Exchange Syntax Standard</a>, PKCS #12 defines an archive file format for storing 254 * many cryptography objects as a single file. 255 * 256 * @since 15.0 257 */ 258 public static final MediaType KEY_ARCHIVE = createConstant(APPLICATION_TYPE, "pkcs12"); 259 /** 260 * This is a non-standard media type, but is commonly used in serving hosted binary files as it is 261 * <a href="http://code.google.com/p/browsersec/wiki/Part2#Survey_of_content_sniffing_behaviors"> 262 * known not to trigger content sniffing in current browsers</a>. It <i>should not</i> be used in 263 * other situations as it is not specified by any RFC and does not appear in the <a href= 264 * "http://www.iana.org/assignments/media-types">/IANA MIME Media Types</a> list. Consider 265 * {@link #OCTET_STREAM} for binary data that is not being served to a browser. 266 * 267 * 268 * @since 14.0 269 */ 270 public static final MediaType APPLICATION_BINARY = createConstant(APPLICATION_TYPE, "binary"); 271 public static final MediaType GZIP = createConstant(APPLICATION_TYPE, "x-gzip"); 272 /** 273 * <a href="http://www.rfc-editor.org/rfc/rfc4329.txt">RFC 4329</a> declares this to be the 274 * correct media type for JavaScript, but {@link #TEXT_JAVASCRIPT_UTF_8 text/javascript} may be 275 * necessary in certain situations for compatibility. 276 */ 277 public static final MediaType JAVASCRIPT_UTF_8 = 278 createConstantUtf8(APPLICATION_TYPE, "javascript"); 279 public static final MediaType JSON_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "json"); 280 public static final MediaType KML = createConstant(APPLICATION_TYPE, "vnd.google-earth.kml+xml"); 281 public static final MediaType KMZ = createConstant(APPLICATION_TYPE, "vnd.google-earth.kmz"); 282 public static final MediaType MBOX = createConstant(APPLICATION_TYPE, "mbox"); 283 public static final MediaType MICROSOFT_EXCEL = createConstant(APPLICATION_TYPE, "vnd.ms-excel"); 284 public static final MediaType MICROSOFT_POWERPOINT = 285 createConstant(APPLICATION_TYPE, "vnd.ms-powerpoint"); 286 public static final MediaType MICROSOFT_WORD = createConstant(APPLICATION_TYPE, "msword"); 287 public static final MediaType OCTET_STREAM = createConstant(APPLICATION_TYPE, "octet-stream"); 288 public static final MediaType OGG_CONTAINER = createConstant(APPLICATION_TYPE, "ogg"); 289 public static final MediaType OOXML_DOCUMENT = createConstant(APPLICATION_TYPE, 290 "vnd.openxmlformats-officedocument.wordprocessingml.document"); 291 public static final MediaType OOXML_PRESENTATION = createConstant(APPLICATION_TYPE, 292 "vnd.openxmlformats-officedocument.presentationml.presentation"); 293 public static final MediaType OOXML_SHEET = 294 createConstant(APPLICATION_TYPE, "vnd.openxmlformats-officedocument.spreadsheetml.sheet"); 295 public static final MediaType OPENDOCUMENT_GRAPHICS = 296 createConstant(APPLICATION_TYPE, "vnd.oasis.opendocument.graphics"); 297 public static final MediaType OPENDOCUMENT_PRESENTATION = 298 createConstant(APPLICATION_TYPE, "vnd.oasis.opendocument.presentation"); 299 public static final MediaType OPENDOCUMENT_SPREADSHEET = 300 createConstant(APPLICATION_TYPE, "vnd.oasis.opendocument.spreadsheet"); 301 public static final MediaType OPENDOCUMENT_TEXT = 302 createConstant(APPLICATION_TYPE, "vnd.oasis.opendocument.text"); 303 public static final MediaType PDF = createConstant(APPLICATION_TYPE, "pdf"); 304 public static final MediaType POSTSCRIPT = createConstant(APPLICATION_TYPE, "postscript"); 305 /** 306 * <a href="http://tools.ietf.org/html/draft-rfernando-protocol-buffers-00">Protocol buffers</a> 307 * 308 * @since 15.0 309 */ 310 public static final MediaType PROTOBUF = createConstant(APPLICATION_TYPE, "protobuf"); 311 public static final MediaType RDF_XML_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "rdf+xml"); 312 public static final MediaType RTF_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "rtf"); 313 /** 314 * Media type for SFNT fonts (which includes 315 * <a href="http://en.wikipedia.org/wiki/TrueType/">TrueType</a> and 316 * <a href="http://en.wikipedia.org/wiki/OpenType/">OpenType</a> fonts). This is 317 * <a href="http://www.iana.org/assignments/media-types/application/font-sfnt">registered</a> 318 * with the IANA. 319 * 320 * @since 17.0 321 */ 322 public static final MediaType SFNT = createConstant(APPLICATION_TYPE, "font-sfnt"); 323 public static final MediaType SHOCKWAVE_FLASH = createConstant(APPLICATION_TYPE, 324 "x-shockwave-flash"); 325 public static final MediaType SKETCHUP = createConstant(APPLICATION_TYPE, "vnd.sketchup.skp"); 326 public static final MediaType TAR = createConstant(APPLICATION_TYPE, "x-tar"); 327 /** 328 * Media type for the 329 * <a href="http://en.wikipedia.org/wiki/Web_Open_Font_Format">Web Open Font Format</a> (WOFF) 330 * <a href="http://www.w3.org/TR/WOFF/">defined</a> by the W3C. This is 331 * <a href="http://www.iana.org/assignments/media-types/application/font-woff">registered</a> 332 * with the IANA. 333 * 334 * @since 17.0 335 */ 336 public static final MediaType WOFF = createConstant(APPLICATION_TYPE, "font-woff"); 337 public static final MediaType XHTML_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "xhtml+xml"); 338 /** 339 * Media type for Extensible Resource Descriptors. This is not yet registered with the IANA, but 340 * it is specified by OASIS in the 341 * <a href="http://docs.oasis-open.org/xri/xrd/v1.0/cd02/xrd-1.0-cd02.html"> XRD definition</a> 342 * and implemented in projects such as 343 * <a href="http://code.google.com/p/webfinger/">WebFinger</a>. 344 */ 345 public static final MediaType XRD_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "xrd+xml"); 346 public static final MediaType ZIP = createConstant(APPLICATION_TYPE, "zip"); 347 348 private final String type; 349 private final String subtype; 350 private final ImmutableListMultimap<String, String> parameters; 351 352 private MediaType(String type, String subtype, 353 ImmutableListMultimap<String, String> parameters) { 354 this.type = type; 355 this.subtype = subtype; 356 this.parameters = parameters; 357 } 358 359 /** Returns the top-level media type. For example, {@code "text"} in {@code "text/plain"}. */ 360 public String type() { 361 return type; 362 } 363 364 /** Returns the media subtype. For example, {@code "plain"} in {@code "text/plain"}. */ 365 public String subtype() { 366 return subtype; 367 } 368 369 /** Returns a multimap containing the parameters of this media type. */ 370 public ImmutableListMultimap<String, String> parameters() { 371 return parameters; 372 } 373 374 private Map<String, ImmutableMultiset<String>> parametersAsMap() { 375 return Maps.transformValues(parameters.asMap(), 376 new Function<Collection<String>, ImmutableMultiset<String>>() { 377 @Override public ImmutableMultiset<String> apply(Collection<String> input) { 378 return ImmutableMultiset.copyOf(input); 379 } 380 }); 381 } 382 383 /** 384 * Returns an optional charset for the value of the charset parameter if it is specified. 385 * 386 * @throws IllegalStateException if multiple charset values have been set for this media type 387 * @throws IllegalCharsetNameException if a charset value is present, but illegal 388 * @throws UnsupportedCharsetException if a charset value is present, but no support is available 389 * in this instance of the Java virtual machine 390 */ 391 public Optional<Charset> charset() { 392 ImmutableSet<String> charsetValues = ImmutableSet.copyOf(parameters.get(CHARSET_ATTRIBUTE)); 393 switch (charsetValues.size()) { 394 case 0: 395 return Optional.absent(); 396 case 1: 397 return Optional.of(Charset.forName(Iterables.getOnlyElement(charsetValues))); 398 default: 399 throw new IllegalStateException("Multiple charset values defined: " + charsetValues); 400 } 401 } 402 403 /** 404 * Returns a new instance with the same type and subtype as this instance, but without any 405 * parameters. 406 */ 407 public MediaType withoutParameters() { 408 return parameters.isEmpty() ? this : create(type, subtype); 409 } 410 411 /** 412 * <em>Replaces</em> all parameters with the given parameters. 413 * 414 * @throws IllegalArgumentException if any parameter or value is invalid 415 */ 416 public MediaType withParameters(Multimap<String, String> parameters) { 417 return create(type, subtype, parameters); 418 } 419 420 /** 421 * <em>Replaces</em> all parameters with the given attribute with a single parameter with the 422 * given value. If multiple parameters with the same attributes are necessary use 423 * {@link #withParameters}. Prefer {@link #withCharset} for setting the {@code charset} parameter 424 * when using a {@link Charset} object. 425 * 426 * @throws IllegalArgumentException if either {@code attribute} or {@code value} is invalid 427 */ 428 public MediaType withParameter(String attribute, String value) { 429 checkNotNull(attribute); 430 checkNotNull(value); 431 String normalizedAttribute = normalizeToken(attribute); 432 ImmutableListMultimap.Builder<String, String> builder = ImmutableListMultimap.builder(); 433 for (Entry<String, String> entry : parameters.entries()) { 434 String key = entry.getKey(); 435 if (!normalizedAttribute.equals(key)) { 436 builder.put(key, entry.getValue()); 437 } 438 } 439 builder.put(normalizedAttribute, normalizeParameterValue(normalizedAttribute, value)); 440 MediaType mediaType = new MediaType(type, subtype, builder.build()); 441 // Return one of the constants if the media type is a known type. 442 return Objects.firstNonNull(KNOWN_TYPES.get(mediaType), mediaType); 443 } 444 445 /** 446 * Returns a new instance with the same type and subtype as this instance, with the 447 * {@code charset} parameter set to the {@link Charset#name name} of the given charset. Only one 448 * {@code charset} parameter will be present on the new instance regardless of the number set on 449 * this one. 450 * 451 * <p>If a charset must be specified that is not supported on this JVM (and thus is not 452 * representable as a {@link Charset} instance, use {@link #withParameter}. 453 */ 454 public MediaType withCharset(Charset charset) { 455 checkNotNull(charset); 456 return withParameter(CHARSET_ATTRIBUTE, charset.name()); 457 } 458 459 /** Returns true if either the type or subtype is the wildcard. */ 460 public boolean hasWildcard() { 461 return WILDCARD.equals(type) || WILDCARD.equals(subtype); 462 } 463 464 /** 465 * Returns {@code true} if this instance falls within the range (as defined by 466 * <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html">the HTTP Accept header</a>) 467 * given by the argument according to three criteria: 468 * 469 * <ol> 470 * <li>The type of the argument is the wildcard or equal to the type of this instance. 471 * <li>The subtype of the argument is the wildcard or equal to the subtype of this instance. 472 * <li>All of the parameters present in the argument are present in this instance. 473 * </ol> 474 * 475 * <p>For example: <pre> {@code 476 * PLAIN_TEXT_UTF_8.is(PLAIN_TEXT_UTF_8) // true 477 * PLAIN_TEXT_UTF_8.is(HTML_UTF_8) // false 478 * PLAIN_TEXT_UTF_8.is(ANY_TYPE) // true 479 * PLAIN_TEXT_UTF_8.is(ANY_TEXT_TYPE) // true 480 * PLAIN_TEXT_UTF_8.is(ANY_IMAGE_TYPE) // false 481 * PLAIN_TEXT_UTF_8.is(ANY_TEXT_TYPE.withCharset(UTF_8)) // true 482 * PLAIN_TEXT_UTF_8.withoutParameters().is(ANY_TEXT_TYPE.withCharset(UTF_8)) // false 483 * PLAIN_TEXT_UTF_8.is(ANY_TEXT_TYPE.withCharset(UTF_16)) // false}</pre> 484 * 485 * <p>Note that while it is possible to have the same parameter declared multiple times within a 486 * media type this method does not consider the number of occurrences of a parameter. For 487 * example, {@code "text/plain; charset=UTF-8"} satisfies 488 * {@code "text/plain; charset=UTF-8; charset=UTF-8"}. 489 */ 490 public boolean is(MediaType mediaTypeRange) { 491 return (mediaTypeRange.type.equals(WILDCARD) || mediaTypeRange.type.equals(this.type)) 492 && (mediaTypeRange.subtype.equals(WILDCARD) || mediaTypeRange.subtype.equals(this.subtype)) 493 && this.parameters.entries().containsAll(mediaTypeRange.parameters.entries()); 494 } 495 496 /** 497 * Creates a new media type with the given type and subtype. 498 * 499 * @throws IllegalArgumentException if type or subtype is invalid or if a wildcard is used for the 500 * type, but not the subtype. 501 */ 502 public static MediaType create(String type, String subtype) { 503 return create(type, subtype, ImmutableListMultimap.<String, String>of()); 504 } 505 506 /** 507 * Creates a media type with the "application" type and the given subtype. 508 * 509 * @throws IllegalArgumentException if subtype is invalid 510 */ 511 static MediaType createApplicationType(String subtype) { 512 return create(APPLICATION_TYPE, subtype); 513 } 514 515 /** 516 * Creates a media type with the "audio" type and the given subtype. 517 * 518 * @throws IllegalArgumentException if subtype is invalid 519 */ 520 static MediaType createAudioType(String subtype) { 521 return create(AUDIO_TYPE, subtype); 522 } 523 524 /** 525 * Creates a media type with the "image" type and the given subtype. 526 * 527 * @throws IllegalArgumentException if subtype is invalid 528 */ 529 static MediaType createImageType(String subtype) { 530 return create(IMAGE_TYPE, subtype); 531 } 532 533 /** 534 * Creates a media type with the "text" type and the given subtype. 535 * 536 * @throws IllegalArgumentException if subtype is invalid 537 */ 538 static MediaType createTextType(String subtype) { 539 return create(TEXT_TYPE, subtype); 540 } 541 542 /** 543 * Creates a media type with the "video" type and the given subtype. 544 * 545 * @throws IllegalArgumentException if subtype is invalid 546 */ 547 static MediaType createVideoType(String subtype) { 548 return create(VIDEO_TYPE, subtype); 549 } 550 551 private static MediaType create(String type, String subtype, 552 Multimap<String, String> parameters) { 553 checkNotNull(type); 554 checkNotNull(subtype); 555 checkNotNull(parameters); 556 String normalizedType = normalizeToken(type); 557 String normalizedSubtype = normalizeToken(subtype); 558 checkArgument(!WILDCARD.equals(normalizedType) || WILDCARD.equals(normalizedSubtype), 559 "A wildcard type cannot be used with a non-wildcard subtype"); 560 ImmutableListMultimap.Builder<String, String> builder = ImmutableListMultimap.builder(); 561 for (Entry<String, String> entry : parameters.entries()) { 562 String attribute = normalizeToken(entry.getKey()); 563 builder.put(attribute, normalizeParameterValue(attribute, entry.getValue())); 564 } 565 MediaType mediaType = new MediaType(normalizedType, normalizedSubtype, builder.build()); 566 // Return one of the constants if the media type is a known type. 567 return Objects.firstNonNull(KNOWN_TYPES.get(mediaType), mediaType); 568 } 569 570 private static String normalizeToken(String token) { 571 checkArgument(TOKEN_MATCHER.matchesAllOf(token)); 572 return Ascii.toLowerCase(token); 573 } 574 575 private static String normalizeParameterValue(String attribute, String value) { 576 return CHARSET_ATTRIBUTE.equals(attribute) ? Ascii.toLowerCase(value) : value; 577 } 578 579 /** 580 * Parses a media type from its string representation. 581 * 582 * @throws IllegalArgumentException if the input is not parsable 583 */ 584 public static MediaType parse(String input) { 585 checkNotNull(input); 586 Tokenizer tokenizer = new Tokenizer(input); 587 try { 588 String type = tokenizer.consumeToken(TOKEN_MATCHER); 589 tokenizer.consumeCharacter('/'); 590 String subtype = tokenizer.consumeToken(TOKEN_MATCHER); 591 ImmutableListMultimap.Builder<String, String> parameters = ImmutableListMultimap.builder(); 592 while (tokenizer.hasMore()) { 593 tokenizer.consumeCharacter(';'); 594 tokenizer.consumeTokenIfPresent(LINEAR_WHITE_SPACE); 595 String attribute = tokenizer.consumeToken(TOKEN_MATCHER); 596 tokenizer.consumeCharacter('='); 597 final String value; 598 if ('"' == tokenizer.previewChar()) { 599 tokenizer.consumeCharacter('"'); 600 StringBuilder valueBuilder = new StringBuilder(); 601 while ('"' != tokenizer.previewChar()) { 602 if ('\\' == tokenizer.previewChar()) { 603 tokenizer.consumeCharacter('\\'); 604 valueBuilder.append(tokenizer.consumeCharacter(ASCII)); 605 } else { 606 valueBuilder.append(tokenizer.consumeToken(QUOTED_TEXT_MATCHER)); 607 } 608 } 609 value = valueBuilder.toString(); 610 tokenizer.consumeCharacter('"'); 611 } else { 612 value = tokenizer.consumeToken(TOKEN_MATCHER); 613 } 614 parameters.put(attribute, value); 615 } 616 return create(type, subtype, parameters.build()); 617 } catch (IllegalStateException e) { 618 throw new IllegalArgumentException("Could not parse '" + input + "'", e); 619 } 620 } 621 622 private static final class Tokenizer { 623 final String input; 624 int position = 0; 625 626 Tokenizer(String input) { 627 this.input = input; 628 } 629 630 String consumeTokenIfPresent(CharMatcher matcher) { 631 checkState(hasMore()); 632 int startPosition = position; 633 position = matcher.negate().indexIn(input, startPosition); 634 return hasMore() ? input.substring(startPosition, position) : input.substring(startPosition); 635 } 636 637 String consumeToken(CharMatcher matcher) { 638 int startPosition = position; 639 String token = consumeTokenIfPresent(matcher); 640 checkState(position != startPosition); 641 return token; 642 } 643 644 char consumeCharacter(CharMatcher matcher) { 645 checkState(hasMore()); 646 char c = previewChar(); 647 checkState(matcher.matches(c)); 648 position++; 649 return c; 650 } 651 652 char consumeCharacter(char c) { 653 checkState(hasMore()); 654 checkState(previewChar() == c); 655 position++; 656 return c; 657 } 658 659 char previewChar() { 660 checkState(hasMore()); 661 return input.charAt(position); 662 } 663 664 boolean hasMore() { 665 return (position >= 0) && (position < input.length()); 666 } 667 } 668 669 @Override public boolean equals(@Nullable Object obj) { 670 if (obj == this) { 671 return true; 672 } else if (obj instanceof MediaType) { 673 MediaType that = (MediaType) obj; 674 return this.type.equals(that.type) 675 && this.subtype.equals(that.subtype) 676 // compare parameters regardless of order 677 && this.parametersAsMap().equals(that.parametersAsMap()); 678 } else { 679 return false; 680 } 681 } 682 683 @Override public int hashCode() { 684 return Objects.hashCode(type, subtype, parametersAsMap()); 685 } 686 687 private static final MapJoiner PARAMETER_JOINER = Joiner.on("; ").withKeyValueSeparator("="); 688 689 /** 690 * Returns the string representation of this media type in the format described in <a 691 * href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a>. 692 */ 693 @Override public String toString() { 694 StringBuilder builder = new StringBuilder().append(type).append('/').append(subtype); 695 if (!parameters.isEmpty()) { 696 builder.append("; "); 697 Multimap<String, String> quotedParameters = Multimaps.transformValues(parameters, 698 new Function<String, String>() { 699 @Override public String apply(String value) { 700 return TOKEN_MATCHER.matchesAllOf(value) ? value : escapeAndQuote(value); 701 } 702 }); 703 PARAMETER_JOINER.appendTo(builder, quotedParameters.entries()); 704 } 705 return builder.toString(); 706 } 707 708 private static String escapeAndQuote(String value) { 709 StringBuilder escaped = new StringBuilder(value.length() + 16).append('"'); 710 for (char ch : value.toCharArray()) { 711 if (ch == '\r' || ch == '\\' || ch == '"') { 712 escaped.append('\\'); 713 } 714 escaped.append(ch); 715 } 716 return escaped.append('"').toString(); 717 } 718 719}