https://github.com/google/guava/guava: Guava is a suite of core and expanded libraries that include utility classes, google's collections, io classes, and much much more. 
/*
 * Copyright (C) 2011 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.net;

import static com.google.common.base.CharMatcher.ascii;
import static com.google.common.base.CharMatcher.javaIsoControl;
import static com.google.common.base.Charsets.UTF_8;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;

import com.google.common.annotations.Beta;
import com.google.common.annotations.GwtCompatible;
import com.google.common.base.Ascii;
import com.google.common.base.CharMatcher;
import com.google.common.base.Function;
import com.google.common.base.Joiner;
import com.google.common.base.Joiner.MapJoiner;
import com.google.common.base.MoreObjects;
import com.google.common.base.Objects;
import com.google.common.base.Optional;
import com.google.common.collect.ImmutableListMultimap;
import com.google.common.collect.ImmutableMultiset;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Maps;
import com.google.common.collect.Multimap;
import com.google.common.collect.Multimaps;
import com.google.errorprone.annotations.Immutable;
import com.google.errorprone.annotations.concurrent.LazyInit;
import java.nio.charset.Charset;
import java.nio.charset.IllegalCharsetNameException;
import java.nio.charset.UnsupportedCharsetException;
import java.util.Collection;
import java.util.Map;
import java.util.Map.Entry;
import org.checkerframework.checker.nullness.qual.Nullable;


Represents an Internet Media Type
(also known as a MIME Type or Content Type). This class also supports the concept of media ranges
defined by HTTP/1.1. As such, the * character is treated as a wildcard and is used to represent any acceptable type or subtype value. A media type may not have wildcard type with a declared subtype. The * character has no special meaning as part of a parameter. All values for type, subtype, parameter attributes or parameter values must be valid according to RFCs 2045 and 2046.

All portions of the media type that are case-insensitive (type, subtype, parameter attributes) are normalized to lowercase. The value of the charset parameter is normalized to lowercase, but all others are left as-is. 
Note that this specifically does not represent the value of the MIME 
Content-Type header and as such has no support for header-specific considerations such as line folding and comments. 
For media types that take a charset the predefined constants default to UTF-8 and have a "_UTF_8" suffix. To get a version without a character set, use withoutParameters. 
Author:Gregory Kick
Since:12.0
/**
 * Represents an <a href="http://en.wikipedia.org/wiki/Internet_media_type">Internet Media Type</a>
 * (also known as a MIME Type or Content Type). This class also supports the concept of media ranges
 * <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.1">defined by HTTP/1.1</a>.
 * As such, the {@code *} character is treated as a wildcard and is used to represent any acceptable
 * type or subtype value. A media type may not have wildcard type with a declared subtype. The
 * {@code *} character has no special meaning as part of a parameter. All values for type, subtype,
 * parameter attributes or parameter values must be valid according to RFCs <a
 * href="http://www.ietf.org/rfc/rfc2045.txt">2045</a> and <a
 * href="http://www.ietf.org/rfc/rfc2046.txt">2046</a>.
 *
 * <p>All portions of the media type that are case-insensitive (type, subtype, parameter attributes)
 * are normalized to lowercase. The value of the {@code charset} parameter is normalized to
 * lowercase, but all others are left as-is.
 *
 * <p>Note that this specifically does <strong>not</strong> represent the value of the MIME {@code
 * Content-Type} header and as such has no support for header-specific considerations such as line
 * folding and comments.
 *
 * <p>For media types that take a charset the predefined constants default to UTF-8 and have a
 * "_UTF_8" suffix. To get a version without a character set, use {@link #withoutParameters}.
 *
 * @since 12.0
 * @author Gregory Kick
 */
@Beta
@GwtCompatible
@Immutable
public final class MediaType {
  private static final String CHARSET_ATTRIBUTE = "charset";
  private static final ImmutableListMultimap<String, String> UTF_8_CONSTANT_PARAMETERS =
      ImmutableListMultimap.of(CHARSET_ATTRIBUTE, Ascii.toLowerCase(UTF_8.name()));

  
Matcher for type, subtype and attributes. 
/** Matcher for type, subtype and attributes. */
  private static final CharMatcher TOKEN_MATCHER =
      ascii()
          .and(javaIsoControl().negate())
          .and(CharMatcher.isNot(' '))
          .and(CharMatcher.noneOf("()<>@,;:\\\"/[]?="));

  private static final CharMatcher QUOTED_TEXT_MATCHER = ascii().and(CharMatcher.noneOf("\"\\\r"));
  /*
   * This matches the same characters as linear-white-space from RFC 822, but we make no effort to
   * enforce any particular rules with regards to line folding as stated in the class docs.
   */
  private static final CharMatcher LINEAR_WHITE_SPACE = CharMatcher.anyOf(" \t\r\n");

  // TODO(gak): make these public?
  private static final String APPLICATION_TYPE = "application";
  private static final String AUDIO_TYPE = "audio";
  private static final String IMAGE_TYPE = "image";
  private static final String TEXT_TYPE = "text";
  private static final String VIDEO_TYPE = "video";

  private static final String WILDCARD = "*";

  private static final Map<MediaType, MediaType> KNOWN_TYPES = Maps.newHashMap();

  private static MediaType createConstant(String type, String subtype) {
    MediaType mediaType =
        addKnownType(new MediaType(type, subtype, ImmutableListMultimap.<String, String>of()));
    mediaType.parsedCharset = Optional.absent();
    return mediaType;
  }

  private static MediaType createConstantUtf8(String type, String subtype) {
    MediaType mediaType = addKnownType(new MediaType(type, subtype, UTF_8_CONSTANT_PARAMETERS));
    mediaType.parsedCharset = Optional.of(UTF_8);
    return mediaType;
  }

  private static MediaType addKnownType(MediaType mediaType) {
    KNOWN_TYPES.put(mediaType, mediaType);
    return mediaType;
  }

  /*
   * The following constants are grouped by their type and ordered alphabetically by the constant
   * name within that type. The constant name should be a sensible identifier that is closest to the
   * "common name" of the media. This is often, but not necessarily the same as the subtype.
   *
   * Be sure to declare all constants with the type and subtype in all lowercase. For types that
   * take a charset (e.g. all text/* types), default to UTF-8 and suffix the constant name with
   * "_UTF_8".
   */

  public static final MediaType ANY_TYPE = createConstant(WILDCARD, WILDCARD);
  public static final MediaType ANY_TEXT_TYPE = createConstant(TEXT_TYPE, WILDCARD);
  public static final MediaType ANY_IMAGE_TYPE = createConstant(IMAGE_TYPE, WILDCARD);
  public static final MediaType ANY_AUDIO_TYPE = createConstant(AUDIO_TYPE, WILDCARD);
  public static final MediaType ANY_VIDEO_TYPE = createConstant(VIDEO_TYPE, WILDCARD);
  public static final MediaType ANY_APPLICATION_TYPE = createConstant(APPLICATION_TYPE, WILDCARD);

  /* text types */
  public static final MediaType CACHE_MANIFEST_UTF_8 =
      createConstantUtf8(TEXT_TYPE, "cache-manifest");
  public static final MediaType CSS_UTF_8 = createConstantUtf8(TEXT_TYPE, "css");
  public static final MediaType CSV_UTF_8 = createConstantUtf8(TEXT_TYPE, "csv");
  public static final MediaType HTML_UTF_8 = createConstantUtf8(TEXT_TYPE, "html");
  public static final MediaType I_CALENDAR_UTF_8 = createConstantUtf8(TEXT_TYPE, "calendar");
  public static final MediaType PLAIN_TEXT_UTF_8 = createConstantUtf8(TEXT_TYPE, "plain");
  
RFC 4329 declares application/javascript to be the correct media type for JavaScript, but this may be necessary in certain situations for compatibility. 
/**
   * <a href="http://www.rfc-editor.org/rfc/rfc4329.txt">RFC 4329</a> declares {@link
   * #JAVASCRIPT_UTF_8 application/javascript} to be the correct media type for JavaScript, but this
   * may be necessary in certain situations for compatibility.
   */
  public static final MediaType TEXT_JAVASCRIPT_UTF_8 = createConstantUtf8(TEXT_TYPE, "javascript");
  
Since:15.0
/**
   * <a href="http://www.iana.org/assignments/media-types/text/tab-separated-values">Tab separated
   * values</a>.
   *
   * @since 15.0
   */
  public static final MediaType TSV_UTF_8 = createConstantUtf8(TEXT_TYPE, "tab-separated-values");

  public static final MediaType VCARD_UTF_8 = createConstantUtf8(TEXT_TYPE, "vcard");
  public static final MediaType WML_UTF_8 = createConstantUtf8(TEXT_TYPE, "vnd.wap.wml");
  
As described in RFC 3023, this constant (text/xml) is used for XML documents that are "readable by casual users." APPLICATION_XML_UTF_8 is provided for documents that are intended for applications. 
/**
   * As described in <a href="http://www.ietf.org/rfc/rfc3023.txt">RFC 3023</a>, this constant
   * ({@code text/xml}) is used for XML documents that are "readable by casual users." {@link
   * #APPLICATION_XML_UTF_8} is provided for documents that are intended for applications.
   */
  public static final MediaType XML_UTF_8 = createConstantUtf8(TEXT_TYPE, "xml");
  
As described in the VTT spec, this is
used for Web Video Text Tracks (WebVTT) files, used with the HTML5 track element.

Since:20.0
/**
   * As described in <a href="https://w3c.github.io/webvtt/#iana-text-vtt">the VTT spec</a>, this is
   * used for Web Video Text Tracks (WebVTT) files, used with the HTML5 track element.
   *
   * @since 20.0
   */
  public static final MediaType VTT_UTF_8 = createConstantUtf8(TEXT_TYPE, "vtt");

  /* image types */
  public static final MediaType BMP = createConstant(IMAGE_TYPE, "bmp");
  
The media type for the Canon
Image File Format (crw files), a widely-used "raw image" format for cameras. It is found in /etc/mime.types, e.g. in Debian 3.48-1.

Since:15.0
/**
   * The media type for the <a href="http://en.wikipedia.org/wiki/Camera_Image_File_Format">Canon
   * Image File Format</a> ({@code crw} files), a widely-used "raw image" format for cameras. It is
   * found in {@code /etc/mime.types}, e.g. in <a href=
   * "http://anonscm.debian.org/gitweb/?p=collab-maint/mime-support.git;a=blob;f=mime.types;hb=HEAD"
   * >Debian 3.48-1</a>.
   *
   * @since 15.0
   */
  public static final MediaType CRW = createConstant(IMAGE_TYPE, "x-canon-crw");

  public static final MediaType GIF = createConstant(IMAGE_TYPE, "gif");
  public static final MediaType ICO = createConstant(IMAGE_TYPE, "vnd.microsoft.icon");
  public static final MediaType JPEG = createConstant(IMAGE_TYPE, "jpeg");
  public static final MediaType PNG = createConstant(IMAGE_TYPE, "png");
  
The media type for the Photoshop File Format (psd files) as defined by IANA, and found in /etc/mime.types, e.g.  of the
Apache HTTPD project; for the specification, see 
Adobe Photoshop Document Format and Wikipedia; this is the
regular output/input of Photoshop (which can also export to various image formats; note that
files with extension "PSB" are in a distinct but related format).

This is a more recent replacement for the older, experimental type x-photoshop: RFC-2046.6.

Since:15.0
/**
   * The media type for the Photoshop File Format ({@code psd} files) as defined by <a
   * href="http://www.iana.org/assignments/media-types/image/vnd.adobe.photoshop">IANA</a>, and
   * found in {@code /etc/mime.types}, e.g. <a
   * href="http://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x/conf/mime.types"></a> of the
   * Apache <a href="http://httpd.apache.org/">HTTPD project</a>; for the specification, see <a
   * href="http://www.adobe.com/devnet-apps/photoshop/fileformatashtml/PhotoshopFileFormats.htm">
   * Adobe Photoshop Document Format</a> and <a
   * href="http://en.wikipedia.org/wiki/Adobe_Photoshop#File_format">Wikipedia</a>; this is the
   * regular output/input of Photoshop (which can also export to various image formats; note that
   * files with extension "PSB" are in a distinct but related format).
   *
   * <p>This is a more recent replacement for the older, experimental type {@code x-photoshop}: <a
   * href="http://tools.ietf.org/html/rfc2046#section-6">RFC-2046.6</a>.
   *
   * @since 15.0
   */
  public static final MediaType PSD = createConstant(IMAGE_TYPE, "vnd.adobe.photoshop");

  public static final MediaType SVG_UTF_8 = createConstantUtf8(IMAGE_TYPE, "svg+xml");
  public static final MediaType TIFF = createConstant(IMAGE_TYPE, "tiff");
  public static final MediaType WEBP = createConstant(IMAGE_TYPE, "webp");

  /* audio types */
  public static final MediaType MP4_AUDIO = createConstant(AUDIO_TYPE, "mp4");
  public static final MediaType MPEG_AUDIO = createConstant(AUDIO_TYPE, "mpeg");
  public static final MediaType OGG_AUDIO = createConstant(AUDIO_TYPE, "ogg");
  public static final MediaType WEBM_AUDIO = createConstant(AUDIO_TYPE, "webm");

  
Media type for L16 audio, as defined by RFC
2586.

Since:24.1
/**
   * Media type for L16 audio, as defined by <a href="https://tools.ietf.org/html/rfc2586">RFC
   * 2586</a>.
   *
   * @since 24.1
   */
  public static final MediaType L16_AUDIO = createConstant(AUDIO_TYPE, "l16");

  
Media type for L24 audio, as defined by RFC
3190.

Since:20.0
/**
   * Media type for L24 audio, as defined by <a href="https://tools.ietf.org/html/rfc3190">RFC
   * 3190</a>.
   *
   * @since 20.0
   */
  public static final MediaType L24_AUDIO = createConstant(AUDIO_TYPE, "l24");

  
Media type for Basic Audio, as defined by RFC 2046.

Since:20.0
/**
   * Media type for Basic Audio, as defined by <a
   * href="http://tools.ietf.org/html/rfc2046#section-4.3">RFC 2046</a>.
   *
   * @since 20.0
   */
  public static final MediaType BASIC_AUDIO = createConstant(AUDIO_TYPE, "basic");

  
Media type for Advanced Audio Coding. For more information, see Advanced Audio Coding.

Since:20.0
/**
   * Media type for Advanced Audio Coding. For more information, see <a
   * href="https://en.wikipedia.org/wiki/Advanced_Audio_Coding">Advanced Audio Coding</a>.
   *
   * @since 20.0
   */
  public static final MediaType AAC_AUDIO = createConstant(AUDIO_TYPE, "aac");

  
Media type for Vorbis Audio, as defined by RFC
5215.

Since:20.0
/**
   * Media type for Vorbis Audio, as defined by <a href="http://tools.ietf.org/html/rfc5215">RFC
   * 5215</a>.
   *
   * @since 20.0
   */
  public static final MediaType VORBIS_AUDIO = createConstant(AUDIO_TYPE, "vorbis");

  
Media type for Windows Media Audio. For more information, see file
name extensions for Windows Media metafiles.

Since:20.0
/**
   * Media type for Windows Media Audio. For more information, see <a
   * href="https://msdn.microsoft.com/en-us/library/windows/desktop/dd562994(v=vs.85).aspx">file
   * name extensions for Windows Media metafiles</a>.
   *
   * @since 20.0
   */
  public static final MediaType WMA_AUDIO = createConstant(AUDIO_TYPE, "x-ms-wma");

  
Media type for Windows Media metafiles. For more information, see file
name extensions for Windows Media metafiles.

Since:20.0
/**
   * Media type for Windows Media metafiles. For more information, see <a
   * href="https://msdn.microsoft.com/en-us/library/windows/desktop/dd562994(v=vs.85).aspx">file
   * name extensions for Windows Media metafiles</a>.
   *
   * @since 20.0
   */
  public static final MediaType WAX_AUDIO = createConstant(AUDIO_TYPE, "x-ms-wax");

  
Media type for Real Audio. For more information, see this link.

Since:20.0
/**
   * Media type for Real Audio. For more information, see <a
   * href="http://service.real.com/help/faq/rp8/configrp8win.html">this link</a>.
   *
   * @since 20.0
   */
  public static final MediaType VND_REAL_AUDIO = createConstant(AUDIO_TYPE, "vnd.rn-realaudio");

  
Media type for WAVE format, as defined by RFC
2361.

Since:20.0
/**
   * Media type for WAVE format, as defined by <a href="https://tools.ietf.org/html/rfc2361">RFC
   * 2361</a>.
   *
   * @since 20.0
   */
  public static final MediaType VND_WAVE_AUDIO = createConstant(AUDIO_TYPE, "vnd.wave");

  /* video types */
  public static final MediaType MP4_VIDEO = createConstant(VIDEO_TYPE, "mp4");
  public static final MediaType MPEG_VIDEO = createConstant(VIDEO_TYPE, "mpeg");
  public static final MediaType OGG_VIDEO = createConstant(VIDEO_TYPE, "ogg");
  public static final MediaType QUICKTIME = createConstant(VIDEO_TYPE, "quicktime");
  public static final MediaType WEBM_VIDEO = createConstant(VIDEO_TYPE, "webm");
  public static final MediaType WMV = createConstant(VIDEO_TYPE, "x-ms-wmv");

  
Media type for Flash video. For more information, see this link.

Since:20.0
/**
   * Media type for Flash video. For more information, see <a href=
   * "http://help.adobe.com/en_US/ActionScript/3.0_ProgrammingAS3/WS5b3ccc516d4fbf351e63e3d118a9b90204-7d48.html"
   * >this link</a>.
   *
   * @since 20.0
   */
  public static final MediaType FLV_VIDEO = createConstant(VIDEO_TYPE, "x-flv");

  
Media type for the 3GP multimedia container format. For more information, see 3GPP TS
26.244.

Since:20.0
/**
   * Media type for the 3GP multimedia container format. For more information, see <a
   * href="ftp://www.3gpp.org/tsg_sa/TSG_SA/TSGS_23/Docs/PDF/SP-040065.pdf#page=10">3GPP TS
   * 26.244</a>.
   *
   * @since 20.0
   */
  public static final MediaType THREE_GPP_VIDEO = createConstant(VIDEO_TYPE, "3gpp");

  
Media type for the 3G2 multimedia container format. For more information, see 3GPP2
C.S0050-B.

Since:20.0
/**
   * Media type for the 3G2 multimedia container format. For more information, see <a
   * href="http://www.3gpp2.org/Public_html/specs/C.S0050-B_v1.0_070521.pdf#page=16">3GPP2
   * C.S0050-B</a>.
   *
   * @since 20.0
   */
  public static final MediaType THREE_GPP2_VIDEO = createConstant(VIDEO_TYPE, "3gpp2");

  /* application types */
  
As described in RFC 3023, this constant (application/xml) is used for XML documents that are "unreadable by casual users." XML_UTF_8 is provided for documents that may be read by users. 
/**
   * As described in <a href="http://www.ietf.org/rfc/rfc3023.txt">RFC 3023</a>, this constant
   * ({@code application/xml}) is used for XML documents that are "unreadable by casual users."
   * {@link #XML_UTF_8} is provided for documents that may be read by users.
   */
  public static final MediaType APPLICATION_XML_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "xml");

  public static final MediaType ATOM_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "atom+xml");
  public static final MediaType BZIP2 = createConstant(APPLICATION_TYPE, "x-bzip2");

  
Media type for dart files.

Since:19.0
/**
   * Media type for <a href="https://www.dartlang.org/articles/embedding-in-html/">dart files</a>.
   *
   * @since 19.0
   */
  public static final MediaType DART_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "dart");

  
Media type for Apple Passbook.

Since:19.0
/**
   * Media type for <a href="https://goo.gl/2QoMvg">Apple Passbook</a>.
   *
   * @since 19.0
   */
  public static final MediaType APPLE_PASSBOOK =
      createConstant(APPLICATION_TYPE, "vnd.apple.pkpass");

  
Media type for Embedded OpenType
fonts. This is registered
 with the IANA.

Since:17.0
/**
   * Media type for <a href="http://en.wikipedia.org/wiki/Embedded_OpenType">Embedded OpenType</a>
   * fonts. This is <a
   * href="http://www.iana.org/assignments/media-types/application/vnd.ms-fontobject">registered
   * </a> with the IANA.
   *
   * @since 17.0
   */
  public static final MediaType EOT = createConstant(APPLICATION_TYPE, "vnd.ms-fontobject");
  
As described in the International Digital Publishing Forum
EPUB is the distribution and interchange format standard for digital publications and
documents. This media type is defined in the EPUB Open Container Format
specification.

Since:15.0
/**
   * As described in the <a href="http://idpf.org/epub">International Digital Publishing Forum</a>
   * EPUB is the distribution and interchange format standard for digital publications and
   * documents. This media type is defined in the <a
   * href="http://www.idpf.org/epub/30/spec/epub30-ocf.html">EPUB Open Container Format</a>
   * specification.
   *
   * @since 15.0
   */
  public static final MediaType EPUB = createConstant(APPLICATION_TYPE, "epub+zip");

  public static final MediaType FORM_DATA =
      createConstant(APPLICATION_TYPE, "x-www-form-urlencoded");
  
As described in PKCS #12: Personal
Information Exchange Syntax Standard, PKCS #12 defines an archive file format for storing
many cryptography objects as a single file.

Since:15.0
/**
   * As described in <a href="https://www.rsa.com/rsalabs/node.asp?id=2138">PKCS #12: Personal
   * Information Exchange Syntax Standard</a>, PKCS #12 defines an archive file format for storing
   * many cryptography objects as a single file.
   *
   * @since 15.0
   */
  public static final MediaType KEY_ARCHIVE = createConstant(APPLICATION_TYPE, "pkcs12");
  
This is a non-standard media type, but is commonly used in serving hosted binary files as it is

known not to trigger content sniffing in current browsers. It should not be used in
other situations as it is not specified by any RFC and does not appear in the /IANA MIME Media Types list. Consider OCTET_STREAM for binary data that is not being served to a browser. 
Since:14.0
/**
   * This is a non-standard media type, but is commonly used in serving hosted binary files as it is
   * <a href="http://code.google.com/p/browsersec/wiki/Part2#Survey_of_content_sniffing_behaviors">
   * known not to trigger content sniffing in current browsers</a>. It <i>should not</i> be used in
   * other situations as it is not specified by any RFC and does not appear in the <a
   * href="http://www.iana.org/assignments/media-types">/IANA MIME Media Types</a> list. Consider
   * {@link #OCTET_STREAM} for binary data that is not being served to a browser.
   *
   * @since 14.0
   */
  public static final MediaType APPLICATION_BINARY = createConstant(APPLICATION_TYPE, "binary");

  public static final MediaType GZIP = createConstant(APPLICATION_TYPE, "x-gzip");
  
RFC 4329 declares this to be the correct media type for JavaScript, but text/javascript may be necessary in certain situations for compatibility. 
/**
   * <a href="http://www.rfc-editor.org/rfc/rfc4329.txt">RFC 4329</a> declares this to be the
   * correct media type for JavaScript, but {@link #TEXT_JAVASCRIPT_UTF_8 text/javascript} may be
   * necessary in certain situations for compatibility.
   */
  public static final MediaType JAVASCRIPT_UTF_8 =
      createConstantUtf8(APPLICATION_TYPE, "javascript");

  public static final MediaType JSON_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "json");
  
Media type for the Manifest for a web
application.

Since:19.0
/**
   * Media type for the <a href="http://www.w3.org/TR/appmanifest/">Manifest for a web
   * application</a>.
   *
   * @since 19.0
   */
  public static final MediaType MANIFEST_JSON_UTF_8 =
      createConstantUtf8(APPLICATION_TYPE, "manifest+json");

  public static final MediaType KML = createConstant(APPLICATION_TYPE, "vnd.google-earth.kml+xml");
  public static final MediaType KMZ = createConstant(APPLICATION_TYPE, "vnd.google-earth.kmz");
  public static final MediaType MBOX = createConstant(APPLICATION_TYPE, "mbox");

  
Since:18.0
/**
   * Media type for <a href="http://goo.gl/1pGBFm">Apple over-the-air mobile configuration
   * profiles</a>.
   *
   * @since 18.0
   */
  public static final MediaType APPLE_MOBILE_CONFIG =
      createConstant(APPLICATION_TYPE, "x-apple-aspen-config");

  public static final MediaType MICROSOFT_EXCEL = createConstant(APPLICATION_TYPE, "vnd.ms-excel");
  public static final MediaType MICROSOFT_POWERPOINT =
      createConstant(APPLICATION_TYPE, "vnd.ms-powerpoint");
  public static final MediaType MICROSOFT_WORD = createConstant(APPLICATION_TYPE, "msword");

  
Media type for NaCl applications. For more information see the
Developer Guide for Native Client Application Structure.

Since:20.0
/**
   * Media type for NaCl applications. For more information see <a
   * href="https://developer.chrome.com/native-client/devguide/coding/application-structure">the
   * Developer Guide for Native Client Application Structure</a>.
   *
   * @since 20.0
   */
  public static final MediaType NACL_APPLICATION = createConstant(APPLICATION_TYPE, "x-nacl");

  
Media type for NaCl portable applications. For more information see the
Developer Guide for Native Client Application Structure.

Since:20.0
/**
   * Media type for NaCl portable applications. For more information see <a
   * href="https://developer.chrome.com/native-client/devguide/coding/application-structure">the
   * Developer Guide for Native Client Application Structure</a>.
   *
   * @since 20.0
   */
  public static final MediaType NACL_PORTABLE_APPLICATION =
      createConstant(APPLICATION_TYPE, "x-pnacl");

  public static final MediaType OCTET_STREAM = createConstant(APPLICATION_TYPE, "octet-stream");

  public static final MediaType OGG_CONTAINER = createConstant(APPLICATION_TYPE, "ogg");
  public static final MediaType OOXML_DOCUMENT =
      createConstant(
          APPLICATION_TYPE, "vnd.openxmlformats-officedocument.wordprocessingml.document");
  public static final MediaType OOXML_PRESENTATION =
      createConstant(
          APPLICATION_TYPE, "vnd.openxmlformats-officedocument.presentationml.presentation");
  public static final MediaType OOXML_SHEET =
      createConstant(APPLICATION_TYPE, "vnd.openxmlformats-officedocument.spreadsheetml.sheet");
  public static final MediaType OPENDOCUMENT_GRAPHICS =
      createConstant(APPLICATION_TYPE, "vnd.oasis.opendocument.graphics");
  public static final MediaType OPENDOCUMENT_PRESENTATION =
      createConstant(APPLICATION_TYPE, "vnd.oasis.opendocument.presentation");
  public static final MediaType OPENDOCUMENT_SPREADSHEET =
      createConstant(APPLICATION_TYPE, "vnd.oasis.opendocument.spreadsheet");
  public static final MediaType OPENDOCUMENT_TEXT =
      createConstant(APPLICATION_TYPE, "vnd.oasis.opendocument.text");
  public static final MediaType PDF = createConstant(APPLICATION_TYPE, "pdf");
  public static final MediaType POSTSCRIPT = createConstant(APPLICATION_TYPE, "postscript");
  
Since:15.0
/**
   * <a href="http://tools.ietf.org/html/draft-rfernando-protocol-buffers-00">Protocol buffers</a>
   *
   * @since 15.0
   */
  public static final MediaType PROTOBUF = createConstant(APPLICATION_TYPE, "protobuf");

  public static final MediaType RDF_XML_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "rdf+xml");
  public static final MediaType RTF_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "rtf");
  
Media type for SFNT fonts (which includes TrueType and OpenType fonts). This is registered with
the IANA.

Since:17.0
/**
   * Media type for SFNT fonts (which includes <a
   * href="http://en.wikipedia.org/wiki/TrueType/">TrueType</a> and <a
   * href="http://en.wikipedia.org/wiki/OpenType/">OpenType</a> fonts). This is <a
   * href="http://www.iana.org/assignments/media-types/application/font-sfnt">registered</a> with
   * the IANA.
   *
   * @since 17.0
   */
  public static final MediaType SFNT = createConstant(APPLICATION_TYPE, "font-sfnt");

  public static final MediaType SHOCKWAVE_FLASH =
      createConstant(APPLICATION_TYPE, "x-shockwave-flash");
  public static final MediaType SKETCHUP = createConstant(APPLICATION_TYPE, "vnd.sketchup.skp");
  
As described in RFC 3902, this constant (application/soap+xml) is used to identify SOAP 1.2 message envelopes that have been serialized with XML 1.0. 
For SOAP 1.1 messages, see XML_UTF_8 per W3C Note on Simple Object Access Protocol
(SOAP) 1.1

Since:20.0
/**
   * As described in <a href="http://www.ietf.org/rfc/rfc3902.txt">RFC 3902</a>, this constant
   * ({@code application/soap+xml}) is used to identify SOAP 1.2 message envelopes that have been
   * serialized with XML 1.0.
   *
   * <p>For SOAP 1.1 messages, see {@code XML_UTF_8} per <a
   * href="http://www.w3.org/TR/2000/NOTE-SOAP-20000508/">W3C Note on Simple Object Access Protocol
   * (SOAP) 1.1</a>
   *
   * @since 20.0
   */
  public static final MediaType SOAP_XML_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "soap+xml");

  public static final MediaType TAR = createConstant(APPLICATION_TYPE, "x-tar");
  
Media type for the Web Open Font
Format (WOFF) defined by the W3C. This is registered with
the IANA.

Since:17.0
/**
   * Media type for the <a href="http://en.wikipedia.org/wiki/Web_Open_Font_Format">Web Open Font
   * Format</a> (WOFF) <a href="http://www.w3.org/TR/WOFF/">defined</a> by the W3C. This is <a
   * href="http://www.iana.org/assignments/media-types/application/font-woff">registered</a> with
   * the IANA.
   *
   * @since 17.0
   */
  public static final MediaType WOFF = createConstant(APPLICATION_TYPE, "font-woff");
  
Media type for the Web Open Font
Format (WOFF) version 2 defined by the W3C.

Since:20.0
/**
   * Media type for the <a href="http://en.wikipedia.org/wiki/Web_Open_Font_Format">Web Open Font
   * Format</a> (WOFF) version 2 <a href="https://www.w3.org/TR/WOFF2/">defined</a> by the W3C.
   *
   * @since 20.0
   */
  public static final MediaType WOFF2 = createConstant(APPLICATION_TYPE, "font-woff2");

  public static final MediaType XHTML_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "xhtml+xml");
  
Media type for Extensible Resource Descriptors. This is not yet registered with the IANA, but
it is specified by OASIS in the XRD definition and
implemented in projects such as WebFinger.

/**
   * Media type for Extensible Resource Descriptors. This is not yet registered with the IANA, but
   * it is specified by OASIS in the <a
   * href="http://docs.oasis-open.org/xri/xrd/v1.0/cd02/xrd-1.0-cd02.html">XRD definition</a> and
   * implemented in projects such as <a href="http://code.google.com/p/webfinger/">WebFinger</a>.
   */
  public static final MediaType XRD_UTF_8 = createConstantUtf8(APPLICATION_TYPE, "xrd+xml");

  public static final MediaType ZIP = createConstant(APPLICATION_TYPE, "zip");

  private final String type;
  private final String subtype;
  private final ImmutableListMultimap<String, String> parameters;

  @LazyInit private String toString;

  @LazyInit private int hashCode;

  @LazyInit private Optional<Charset> parsedCharset;

  private MediaType(String type, String subtype, ImmutableListMultimap<String, String> parameters) {
    this.type = type;
    this.subtype = subtype;
    this.parameters = parameters;
  }

  
Returns the top-level media type. For example, "text" in "text/plain". 
/** Returns the top-level media type. For example, {@code "text"} in {@code "text/plain"}. */
  public String type() {
    return type;
  }

  
Returns the media subtype. For example, "plain" in "text/plain". 
/** Returns the media subtype. For example, {@code "plain"} in {@code "text/plain"}. */
  public String subtype() {
    return subtype;
  }

  
Returns a multimap containing the parameters of this media type. 
/** Returns a multimap containing the parameters of this media type. */
  public ImmutableListMultimap<String, String> parameters() {
    return parameters;
  }

  private Map<String, ImmutableMultiset<String>> parametersAsMap() {
    return Maps.transformValues(
        parameters.asMap(),
        new Function<Collection<String>, ImmutableMultiset<String>>() {
          @Override
          public ImmutableMultiset<String> apply(Collection<String> input) {
            return ImmutableMultiset.copyOf(input);
          }
        });
  }

  
Returns an optional charset for the value of the charset parameter if it is specified.

Throws:
  • IllegalStateException – if multiple charset values have been set for this media type
  • IllegalCharsetNameException – if a charset value is present, but illegal
  • UnsupportedCharsetException – if a charset value is present, but no support is available
    in this instance of the Java virtual machine
/**
   * Returns an optional charset for the value of the charset parameter if it is specified.
   *
   * @throws IllegalStateException if multiple charset values have been set for this media type
   * @throws IllegalCharsetNameException if a charset value is present, but illegal
   * @throws UnsupportedCharsetException if a charset value is present, but no support is available
   *     in this instance of the Java virtual machine
   */
  public Optional<Charset> charset() {
    // racy single-check idiom, this is safe because Optional is immutable.
    Optional<Charset> local = parsedCharset;
    if (local == null) {
      String value = null;
      local = Optional.absent();
      for (String currentValue : parameters.get(CHARSET_ATTRIBUTE)) {
        if (value == null) {
          value = currentValue;
          local = Optional.of(Charset.forName(value));
        } else if (!value.equals(currentValue)) {
          throw new IllegalStateException(
              "Multiple charset values defined: " + value + ", " + currentValue);
        }
      }
      parsedCharset = local;
    }
    return local;
  }

  
Returns a new instance with the same type and subtype as this instance, but without any
parameters.

/**
   * Returns a new instance with the same type and subtype as this instance, but without any
   * parameters.
   */
  public MediaType withoutParameters() {
    return parameters.isEmpty() ? this : create(type, subtype);
  }

  
Replaces all parameters with the given parameters.

Throws:
  • IllegalArgumentException – if any parameter or value is invalid
/**
   * <em>Replaces</em> all parameters with the given parameters.
   *
   * @throws IllegalArgumentException if any parameter or value is invalid
   */
  public MediaType withParameters(Multimap<String, String> parameters) {
    return create(type, subtype, parameters);
  }

  
Replaces all parameters with the given attribute with parameters using the given
values. If there are no values, any existing parameters with the given attribute are
removed.

Throws:
  • IllegalArgumentException – if either attribute or values is invalid
Since:24.0
/**
   * <em>Replaces</em> all parameters with the given attribute with parameters using the given
   * values. If there are no values, any existing parameters with the given attribute are
   * removed.
   *
   * @throws IllegalArgumentException if either {@code attribute} or {@code values} is invalid
   * @since 24.0
   */
  public MediaType withParameters(String attribute, Iterable<String> values) {
    checkNotNull(attribute);
    checkNotNull(values);
    String normalizedAttribute = normalizeToken(attribute);
    ImmutableListMultimap.Builder<String, String> builder = ImmutableListMultimap.builder();
    for (Entry<String, String> entry : parameters.entries()) {
      String key = entry.getKey();
      if (!normalizedAttribute.equals(key)) {
        builder.put(key, entry.getValue());
      }
    }
    for (String value : values) {
      builder.put(normalizedAttribute, normalizeParameterValue(normalizedAttribute, value));
    }
    MediaType mediaType = new MediaType(type, subtype, builder.build());
    // if the attribute isn't charset, we can just inherit the current parsedCharset
    if (!normalizedAttribute.equals(CHARSET_ATTRIBUTE)) {
      mediaType.parsedCharset = this.parsedCharset;
    }
    // Return one of the constants if the media type is a known type.
    return MoreObjects.firstNonNull(KNOWN_TYPES.get(mediaType), mediaType);
  }

  
Replaces all parameters with the given attribute with a single parameter with the given value. If multiple parameters with the same attributes are necessary use withParameters(String, Iterable<String>). Prefer withCharset for setting the charset parameter when using a Charset object. 
Throws:
/**
   * <em>Replaces</em> all parameters with the given attribute with a single parameter with the
   * given value. If multiple parameters with the same attributes are necessary use {@link
   * #withParameters(String, Iterable)}. Prefer {@link #withCharset} for setting the {@code charset}
   * parameter when using a {@link Charset} object.
   *
   * @throws IllegalArgumentException if either {@code attribute} or {@code value} is invalid
   */
  public MediaType withParameter(String attribute, String value) {
    return withParameters(attribute, ImmutableSet.of(value));
  }

  
Returns a new instance with the same type and subtype as this instance, with the 
charset parameter set to the name of the given charset. Only one 
charset parameter will be present on the new instance regardless of the number set on this one. 
If a charset must be specified that is not supported on this JVM (and thus is not representable as a Charset instance, use withParameter. 
/**
   * Returns a new instance with the same type and subtype as this instance, with the {@code
   * charset} parameter set to the {@link Charset#name name} of the given charset. Only one {@code
   * charset} parameter will be present on the new instance regardless of the number set on this
   * one.
   *
   * <p>If a charset must be specified that is not supported on this JVM (and thus is not
   * representable as a {@link Charset} instance, use {@link #withParameter}.
   */
  public MediaType withCharset(Charset charset) {
    checkNotNull(charset);
    MediaType withCharset = withParameter(CHARSET_ATTRIBUTE, charset.name());
    // precache the charset so we don't need to parse it
    withCharset.parsedCharset = Optional.of(charset);
    return withCharset;
  }

  
Returns true if either the type or subtype is the wildcard. 
/** Returns true if either the type or subtype is the wildcard. */
  public boolean hasWildcard() {
    return WILDCARD.equals(type) || WILDCARD.equals(subtype);
  }

  
Returns true if this instance falls within the range (as defined by the HTTP Accept header) given
by the argument according to three criteria:

    
  
  1. The type of the argument is the wildcard or equal to the type of this instance.
  
  2. The subtype of the argument is the wildcard or equal to the subtype of this instance.
  
  3. All of the parameters present in the argument are present in this instance.



For example:


PLAIN_TEXT_UTF_8.is(PLAIN_TEXT_UTF_8) // true
PLAIN_TEXT_UTF_8.is(HTML_UTF_8) // false
PLAIN_TEXT_UTF_8.is(ANY_TYPE) // true
PLAIN_TEXT_UTF_8.is(ANY_TEXT_TYPE) // true
PLAIN_TEXT_UTF_8.is(ANY_IMAGE_TYPE) // false
PLAIN_TEXT_UTF_8.is(ANY_TEXT_TYPE.withCharset(UTF_8)) // true
PLAIN_TEXT_UTF_8.withoutParameters().is(ANY_TEXT_TYPE.withCharset(UTF_8)) // false
PLAIN_TEXT_UTF_8.is(ANY_TEXT_TYPE.withCharset(UTF_16)) // false



Note that while it is possible to have the same parameter declared multiple times within a media type this method does not consider the number of occurrences of a parameter. For example, "text/plain; charset=UTF-8" satisfies "text/plain; charset=UTF-8;
charset=UTF-8". 
/**
   * Returns {@code true} if this instance falls within the range (as defined by <a
   * href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html">the HTTP Accept header</a>) given
   * by the argument according to three criteria:
   *
   * <ol>
   *   <li>The type of the argument is the wildcard or equal to the type of this instance.
   *   <li>The subtype of the argument is the wildcard or equal to the subtype of this instance.
   *   <li>All of the parameters present in the argument are present in this instance.
   * </ol>
   *
   * <p>For example:
   *
   * <pre>{@code
   * PLAIN_TEXT_UTF_8.is(PLAIN_TEXT_UTF_8) // true
   * PLAIN_TEXT_UTF_8.is(HTML_UTF_8) // false
   * PLAIN_TEXT_UTF_8.is(ANY_TYPE) // true
   * PLAIN_TEXT_UTF_8.is(ANY_TEXT_TYPE) // true
   * PLAIN_TEXT_UTF_8.is(ANY_IMAGE_TYPE) // false
   * PLAIN_TEXT_UTF_8.is(ANY_TEXT_TYPE.withCharset(UTF_8)) // true
   * PLAIN_TEXT_UTF_8.withoutParameters().is(ANY_TEXT_TYPE.withCharset(UTF_8)) // false
   * PLAIN_TEXT_UTF_8.is(ANY_TEXT_TYPE.withCharset(UTF_16)) // false
   * }</pre>
   *
   * <p>Note that while it is possible to have the same parameter declared multiple times within a
   * media type this method does not consider the number of occurrences of a parameter. For example,
   * {@code "text/plain; charset=UTF-8"} satisfies {@code "text/plain; charset=UTF-8;
   * charset=UTF-8"}.
   */
  public boolean is(MediaType mediaTypeRange) {
    return (mediaTypeRange.type.equals(WILDCARD) || mediaTypeRange.type.equals(this.type))
        && (mediaTypeRange.subtype.equals(WILDCARD) || mediaTypeRange.subtype.equals(this.subtype))
        && this.parameters.entries().containsAll(mediaTypeRange.parameters.entries());
  }

  
Creates a new media type with the given type and subtype.

Throws:
  • IllegalArgumentException – if type or subtype is invalid or if a wildcard is used for the
    type, but not the subtype.
/**
   * Creates a new media type with the given type and subtype.
   *
   * @throws IllegalArgumentException if type or subtype is invalid or if a wildcard is used for the
   *     type, but not the subtype.
   */
  public static MediaType create(String type, String subtype) {
    MediaType mediaType = create(type, subtype, ImmutableListMultimap.<String, String>of());
    mediaType.parsedCharset = Optional.absent();
    return mediaType;
  }

  private static MediaType create(
      String type, String subtype, Multimap<String, String> parameters) {
    checkNotNull(type);
    checkNotNull(subtype);
    checkNotNull(parameters);
    String normalizedType = normalizeToken(type);
    String normalizedSubtype = normalizeToken(subtype);
    checkArgument(
        !WILDCARD.equals(normalizedType) || WILDCARD.equals(normalizedSubtype),
        "A wildcard type cannot be used with a non-wildcard subtype");
    ImmutableListMultimap.Builder<String, String> builder = ImmutableListMultimap.builder();
    for (Entry<String, String> entry : parameters.entries()) {
      String attribute = normalizeToken(entry.getKey());
      builder.put(attribute, normalizeParameterValue(attribute, entry.getValue()));
    }
    MediaType mediaType = new MediaType(normalizedType, normalizedSubtype, builder.build());
    // Return one of the constants if the media type is a known type.
    return MoreObjects.firstNonNull(KNOWN_TYPES.get(mediaType), mediaType);
  }

  
Creates a media type with the "application" type and the given subtype.

Throws:
  • IllegalArgumentException – if subtype is invalid
/**
   * Creates a media type with the "application" type and the given subtype.
   *
   * @throws IllegalArgumentException if subtype is invalid
   */
  static MediaType createApplicationType(String subtype) {
    return create(APPLICATION_TYPE, subtype);
  }

  
Creates a media type with the "audio" type and the given subtype.

Throws:
  • IllegalArgumentException – if subtype is invalid
/**
   * Creates a media type with the "audio" type and the given subtype.
   *
   * @throws IllegalArgumentException if subtype is invalid
   */
  static MediaType createAudioType(String subtype) {
    return create(AUDIO_TYPE, subtype);
  }

  
Creates a media type with the "image" type and the given subtype.

Throws:
  • IllegalArgumentException – if subtype is invalid
/**
   * Creates a media type with the "image" type and the given subtype.
   *
   * @throws IllegalArgumentException if subtype is invalid
   */
  static MediaType createImageType(String subtype) {
    return create(IMAGE_TYPE, subtype);
  }

  
Creates a media type with the "text" type and the given subtype.

Throws:
  • IllegalArgumentException – if subtype is invalid
/**
   * Creates a media type with the "text" type and the given subtype.
   *
   * @throws IllegalArgumentException if subtype is invalid
   */
  static MediaType createTextType(String subtype) {
    return create(TEXT_TYPE, subtype);
  }

  
Creates a media type with the "video" type and the given subtype.

Throws:
  • IllegalArgumentException – if subtype is invalid
/**
   * Creates a media type with the "video" type and the given subtype.
   *
   * @throws IllegalArgumentException if subtype is invalid
   */
  static MediaType createVideoType(String subtype) {
    return create(VIDEO_TYPE, subtype);
  }

  private static String normalizeToken(String token) {
    checkArgument(TOKEN_MATCHER.matchesAllOf(token));
    return Ascii.toLowerCase(token);
  }

  private static String normalizeParameterValue(String attribute, String value) {
    return CHARSET_ATTRIBUTE.equals(attribute) ? Ascii.toLowerCase(value) : value;
  }

  
Parses a media type from its string representation.

Throws:
  • IllegalArgumentException – if the input is not parsable
/**
   * Parses a media type from its string representation.
   *
   * @throws IllegalArgumentException if the input is not parsable
   */
  public static MediaType parse(String input) {
    checkNotNull(input);
    Tokenizer tokenizer = new Tokenizer(input);
    try {
      String type = tokenizer.consumeToken(TOKEN_MATCHER);
      tokenizer.consumeCharacter('/');
      String subtype = tokenizer.consumeToken(TOKEN_MATCHER);
      ImmutableListMultimap.Builder<String, String> parameters = ImmutableListMultimap.builder();
      while (tokenizer.hasMore()) {
        tokenizer.consumeTokenIfPresent(LINEAR_WHITE_SPACE);
        tokenizer.consumeCharacter(';');
        tokenizer.consumeTokenIfPresent(LINEAR_WHITE_SPACE);
        String attribute = tokenizer.consumeToken(TOKEN_MATCHER);
        tokenizer.consumeCharacter('=');
        final String value;
        if ('"' == tokenizer.previewChar()) {
          tokenizer.consumeCharacter('"');
          StringBuilder valueBuilder = new StringBuilder();
          while ('"' != tokenizer.previewChar()) {
            if ('\\' == tokenizer.previewChar()) {
              tokenizer.consumeCharacter('\\');
              valueBuilder.append(tokenizer.consumeCharacter(ascii()));
            } else {
              valueBuilder.append(tokenizer.consumeToken(QUOTED_TEXT_MATCHER));
            }
          }
          value = valueBuilder.toString();
          tokenizer.consumeCharacter('"');
        } else {
          value = tokenizer.consumeToken(TOKEN_MATCHER);
        }
        parameters.put(attribute, value);
      }
      return create(type, subtype, parameters.build());
    } catch (IllegalStateException e) {
      throw new IllegalArgumentException("Could not parse '" + input + "'", e);
    }
  }

  private static final class Tokenizer {
    final String input;
    int position = 0;

    Tokenizer(String input) {
      this.input = input;
    }

    String consumeTokenIfPresent(CharMatcher matcher) {
      checkState(hasMore());
      int startPosition = position;
      position = matcher.negate().indexIn(input, startPosition);
      return hasMore() ? input.substring(startPosition, position) : input.substring(startPosition);
    }

    String consumeToken(CharMatcher matcher) {
      int startPosition = position;
      String token = consumeTokenIfPresent(matcher);
      checkState(position != startPosition);
      return token;
    }

    char consumeCharacter(CharMatcher matcher) {
      checkState(hasMore());
      char c = previewChar();
      checkState(matcher.matches(c));
      position++;
      return c;
    }

    char consumeCharacter(char c) {
      checkState(hasMore());
      checkState(previewChar() == c);
      position++;
      return c;
    }

    char previewChar() {
      checkState(hasMore());
      return input.charAt(position);
    }

    boolean hasMore() {
      return (position >= 0) && (position < input.length());
    }
  }

  @Override
  public boolean equals(@Nullable Object obj) {
    if (obj == this) {
      return true;
    } else if (obj instanceof MediaType) {
      MediaType that = (MediaType) obj;
      return this.type.equals(that.type)
          && this.subtype.equals(that.subtype)
          // compare parameters regardless of order
          && this.parametersAsMap().equals(that.parametersAsMap());
    } else {
      return false;
    }
  }

  @Override
  public int hashCode() {
    // racy single-check idiom
    int h = hashCode;
    if (h == 0) {
      h = Objects.hashCode(type, subtype, parametersAsMap());
      hashCode = h;
    }
    return h;
  }

  private static final MapJoiner PARAMETER_JOINER = Joiner.on("; ").withKeyValueSeparator("=");

  
Returns the string representation of this media type in the format described in RFC 2045.

/**
   * Returns the string representation of this media type in the format described in <a
   * href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a>.
   */
  @Override
  public String toString() {
    // racy single-check idiom, safe because String is immutable
    String result = toString;
    if (result == null) {
      result = computeToString();
      toString = result;
    }
    return result;
  }

  private String computeToString() {
    StringBuilder builder = new StringBuilder().append(type).append('/').append(subtype);
    if (!parameters.isEmpty()) {
      builder.append("; ");
      Multimap<String, String> quotedParameters =
          Multimaps.transformValues(
              parameters,
              new Function<String, String>() {
                @Override
                public String apply(String value) {
                  return TOKEN_MATCHER.matchesAllOf(value) ? value : escapeAndQuote(value);
                }
              });
      PARAMETER_JOINER.appendTo(builder, quotedParameters.entries());
    }
    return builder.toString();
  }

  private static String escapeAndQuote(String value) {
    StringBuilder escaped = new StringBuilder(value.length() + 16).append('"');
    for (int i = 0; i < value.length(); i++) {
      char ch = value.charAt(i);
      if (ch == '\r' || ch == '\\' || ch == '"') {
        escaped.append('\\');
      }
      escaped.append(ch);
    }
    return escaped.append('"').toString();
  }
}