public static synchronized MimeTypes getDefaultMimeTypes(ClassLoader classLoader) {
        MimeTypes types = DEFAULT_TYPES;
        if (classLoader != null) {
            types = CLASSLOADER_SPECIFIC_DEFAULT_TYPES.get(classLoader);
        }

        if (types == null) {
            try {
                types = MimeTypesFactory
                        .create("tika-mimetypes.xml", "custom-mimetypes.xml", classLoader);
            } catch (MimeTypeException e) {
                throw new RuntimeException("Unable to parse the default media type registry", e);
            } catch (IOException e) {
                throw new RuntimeException("Unable to read the default media type registry", e);
            }

            if (classLoader == null) {
                DEFAULT_TYPES = types;
            } else {
                CLASSLOADER_SPECIFIC_DEFAULT_TYPES.put(classLoader, types);
            }
        }
        return types;
    }
Get the default MimeTypes. This includes all the built-in
media types, and any custom override ones present.

@param classLoader to use, if not the default
@return MimeTypes default type registry
tika-core/src/main/java/org/apache/tika/mime/MimeTypes.java