private static MimeType parseMimeTypeInternal(String mimeType) {
		int index = mimeType.indexOf(';');
		String fullType = (index >= 0 ? mimeType.substring(0, index) : mimeType).trim();
		if (fullType.isEmpty()) {
			throw new InvalidMimeTypeException(mimeType, "'mimeType' must not be empty");
		}

		// java.net.HttpURLConnection returns a *; q=.2 Accept header
		if (MimeType.WILDCARD_TYPE.equals(fullType)) {
			fullType = "*/*";
		}
		int subIndex = fullType.indexOf('/');
		if (subIndex == -1) {
			throw new InvalidMimeTypeException(mimeType, "does not contain '/'");
		}
		if (subIndex == fullType.length() - 1) {
			throw new InvalidMimeTypeException(mimeType, "does not contain subtype after '/'");
		}
		String type = fullType.substring(0, subIndex);
		String subtype = fullType.substring(subIndex + 1);
		if (MimeType.WILDCARD_TYPE.equals(type) && !MimeType.WILDCARD_TYPE.equals(subtype)) {
			throw new InvalidMimeTypeException(mimeType, "wildcard type is legal only in '*/*' (all mime types)");
		}

		Map<String, String> parameters = null;
		do {
			int nextIndex = index + 1;
			boolean quoted = false;
			while (nextIndex < mimeType.length()) {
				char ch = mimeType.charAt(nextIndex);
				if (ch == ';') {
					if (!quoted) {
						break;
					}
				}
				else if (ch == '"') {
					quoted = !quoted;
				}
				nextIndex++;
			}
			String parameter = mimeType.substring(index + 1, nextIndex).trim();
			if (parameter.length() > 0) {
				if (parameters == null) {
					parameters = new LinkedHashMap<>(4);
				}
				int eqIndex = parameter.indexOf('=');
				if (eqIndex >= 0) {
					String attribute = parameter.substring(0, eqIndex).trim();
					String value = parameter.substring(eqIndex + 1).trim();
					parameters.put(attribute, value);
				}
			}
			index = nextIndex;
		}
		while (index < mimeType.length());

		try {
			return new MimeType(type, subtype, parameters);
		}
		catch (UnsupportedCharsetException ex) {
			throw new InvalidMimeTypeException(mimeType, "unsupported charset '" + ex.getCharsetName() + "'");
		}
		catch (IllegalArgumentException ex) {
			throw new InvalidMimeTypeException(mimeType, ex.getMessage());
		}
	}

public MimeType(String type, String subtype, @Nullable Map<String, String> parameters) {
		Assert.hasLength(type, "'type' must not be empty");
		Assert.hasLength(subtype, "'subtype' must not be empty");
		checkToken(type);
		checkToken(subtype);
		this.type = type.toLowerCase(Locale.ENGLISH);
		this.subtype = subtype.toLowerCase(Locale.ENGLISH);
		if (!CollectionUtils.isEmpty(parameters)) {
			Map<String, String> map = new LinkedCaseInsensitiveMap<>(parameters.size(), Locale.ENGLISH);
			parameters.forEach((parameter, value) -> {
				checkParameters(parameter, value);
				map.put(parameter, value);
			});
			this.parameters = Collections.unmodifiableMap(map);
		}
		else {
			this.parameters = Collections.emptyMap();
		}
	}

Charset.forName("0.01")

Accept: text/html;charset=GBK