* @param cause the cause (which is saved for later retrieval by the {@link #getCause()} method).
     *              (A {@code null} value is permitted, and indicates that the cause is nonexistent or unknown.)
     */
    public CrawlerSystemException(final String message, final Throwable cause) {
        super(message, cause);
    }

    /**

        // Test matching performance
        assertTrue(urlFilter.match("https://site500.com/page"));
        assertFalse(urlFilter.match("https://site500.com/file.exclude500"));
        assertFalse(urlFilter.match("https://unknown.com/page"));
    }

    /** Proxy authentication scheme */
    protected AuthScheme proxyAuthScheme = new BasicScheme();

    /** Proxy credentials */
    protected Credentials proxyCredentials;

    /** Default MIME type for unknown content */
    protected String defaultMimeType = APPLICATION_OCTET_STREAM;

    /** Cookie store for managing cookies */
    protected CookieStore cookieStore = new BasicCookieStore();