*/
  public String retainFrom(CharSequence sequence) {
    return negate().removeFrom(sequence);
  }

  /**
   * Returns a string copy of the input character sequence, with each matching BMP character
   * replaced by a given replacement character. For example:
   *
   * {@snippet :
   * CharMatcher.is('a').replaceFrom("radar", 'o')
   * }
   *
   * ... returns {@code "rodor"}.
   *

    HTTP requests, you can use this interface to replace the real `OkHttpClient`
    with your own mocks or fakes.

    The interface will also let you use OkHttp's API with another HTTP client's
    implementation. This is useful in sandboxed environments like Google App
    Engine.

 *  **OkHttp now does cookies.** We've replaced `java.net.CookieHandler` with

 *
 * Neither of the built-in URL models offer direct access to path segments or query parameters.
 * Manually using `StringBuilder` to assemble these components is cumbersome: do '+' characters get
 * silently replaced with spaces? If a query parameter contains a '&', does that get escaped?
 * By offering methods to read and write individual query parameters directly, application
 * developers are saved from the hassles of encoding and decoding.

        }
        return buf.toString().trim();
    }

    /**
     * Replaces duplicate hosts in the URL using the duplicate host helper.
     *
     * @param url the URL to process
     * @return the URL with duplicate hosts replaced
     */
    protected String replaceDuplicateHost(final String url) {
        try {
            // remove duplicate host

            return replaceWithUnderscores(value);
        }
        return value;
    }

    /**
     * Replaces special characters in a string with underscores for group names.
     *
     * @param value the string to process
     * @return the string with special characters replaced by underscores
     */
    protected String replaceWithUnderscores(final String value) {

 * public static double sqrt(double value) {
 *   if (value < 0) {
 *     throw new IllegalArgumentException("input is negative: " + value);
 *   }
 *   // calculate square root
 * }
 * }
 *
 * <p>to be replaced with the more compact
 *
 * {@snippet :
 * public static double sqrt(double value) {
 *   checkArgument(value >= 0, "input is negative: %s", value);
 *   // calculate square root
 * }
 * }
 *

        final boolean isHttpUrl = url.startsWith("http:") || url.startsWith("https:");

        if (isSmbUrl) {
            url = url.replace("smb:", "file:");
            url = url.replace("smb1:", "file:");
        }

        if (isHttpUrl && isSmbOrFtpUrl) {
            //  smb/ftp->http
            // encode

+&&ce.event.trigger("ajaxStart"),v.type=v.type.toUpperCase(),v.hasContent=!Ft.test(v.type),f=v.url.replace(Rt,""),v.hasContent?v.data&&v.processData&&0===(v.contentType||"").indexOf("application/x-www-form-urlencoded")&&(v.data=v.data.replace(Mt,"+")):(o=v.url.slice(f.length),v.data&&(v.processData||"string"==typeof v.data)&&(f+=(At.test(f)?"&":"?")+v.data,delete v.data),!1===v.cache&&(f=f.replace(It,"$1"),o=(At.test(f)?"&":"?")+"_="+jt.guid+++o),v.url=f+o),v.ifModified&&(ce.lastModified[f]&&T.s...

+&&ce.event.trigger("ajaxStart"),v.type=v.type.toUpperCase(),v.hasContent=!Ft.test(v.type),f=v.url.replace(Rt,""),v.hasContent?v.data&&v.processData&&0===(v.contentType||"").indexOf("application/x-www-form-urlencoded")&&(v.data=v.data.replace(Mt,"+")):(o=v.url.slice(f.length),v.data&&(v.processData||"string"==typeof v.data)&&(f+=(At.test(f)?"&":"?")+v.data,delete v.data),!1===v.cache&&(f=f.replace(It,"$1"),o=(At.test(f)?"&":"?")+"_="+jt.guid+++o),v.url=f+o),v.ifModified&&(ce.lastModified[f]&&T.s...

    }

    /**
     * Creates and returns a new instance of {@link ArrayDeque}.
     *
     * @param <E> the element type of {@link ArrayDeque}
     * @param c the collection of elements to be placed in the deque
     * @return a new instance of {@link ArrayDeque}
     * @see ArrayDeque#ArrayDeque(Collection)
     */
    public static <E> ArrayDeque<E> newArrayDeque(final Collection<? extends E> c) {