* {@code BigInteger.valueOf(2).pow(log2(x, CEILING))}.
   *
   * @throws IllegalArgumentException if {@code x <= 0}
   * @since 20.0
   */
  public static BigInteger ceilingPowerOfTwo(BigInteger x) {
    return BigInteger.ZERO.setBit(log2(x, CEILING));
  }

  /**
   * Returns the largest power of two less than or equal to {@code x}. This is equivalent to {@code

        .setExpectation(-Math.pow(2, 53), DOWN, CEILING, HALF_DOWN, HALF_EVEN)
        .setExpectation(nextDown(-Math.pow(2, 53)), FLOOR, UP, HALF_UP)
        .roundUnnecessaryShouldThrow()
        .test();
  }

  public void testRoundToDouble_negativeTwoToThe54MinusOne() {
    new RoundToDoubleTester(BigDecimal.valueOf((-1L << 54) - 1))
        .setExpectation(-Math.pow(2, 54), DOWN, CEILING, HALF_DOWN, HALF_UP, HALF_EVEN)

    }

    /**
     * Stores crawling information and parameters for the specified session.
     * Creates a new crawling info record if none exists or if create flag is true.
     * Also stores any accumulated information parameters and clears the info map.
     *
     * @param sessionId the session ID for the crawling information
     * @param create if true, creates a new crawling info regardless of existing records

     *          since casting to double is nondecreasing.
     *          Note that the right-hand inequality is no longer strict.
     * Math.sqrt(k * k) <= Math.sqrt(x) <= Math.sqrt((k + 1) * (k + 1))
     *          since Math.sqrt is monotonic.
     * (long) Math.sqrt(k * k) <= (long) Math.sqrt(x) <= (long) Math.sqrt((k + 1) * (k + 1))
     *          since casting to long is monotonic

import org.codelibs.fess.crawler.service.UrlQueueService;

import jakarta.annotation.Resource;

/**
 * The Crawler class is the main class for web crawling. It manages the crawling process,
 * including adding URLs to the queue, filtering URLs, managing crawler threads,
 * and handling the overall crawling lifecycle.
 *
 * <p>It implements the Runnable interface to be executed in a separate thread,

    void testAs_Object_Success() throws PACDecodingException {
        // Test successful casting
        String expected = "test string";
        Object obj = expected;
        String result = ASN1Util.as(String.class, obj);
        assertSame(expected, result);
    }

    @Test
    void testAs_Object_Failure() {
        // Test failed casting
        Object obj = 123; // Integer
        assertThrows(PACDecodingException.class, () -> {

    }

    /**
     * Stores (inserts or updates) a crawling information record.
     * Sets up the store conditions including creation time if not already set,
     * then performs an insert or update operation with immediate refresh.
     *
     * @param crawlingInfo the crawling information entity to store
     * @throws FessSystemException if the crawling information is null
     */

                    return cached.toArray(new SmbFile[0]);
                }
            }
        } catch (Exception e) {
            log.debug("Cached directory listing failed, falling back to direct query", e);
        }
        
        // Fall back to direct server query
        return directory.performDirectEnumeration();
    }
}
```

## 10. Monitoring and Metrics

            } else {
                logger.warn("HC5 client is null, falling back to HC4 client");
                setCrawlerClient(hc4Client);
            }
        } else {
            if (hc4Client != null) {
                setCrawlerClient(hc4Client);
            } else {
                logger.warn("HC4 client is null, falling back to HC5 client");
                setCrawlerClient(hc5Client);
            }

        this.leaseState = leaseState;
    }

    /**
     * Gets the cache scope for directory enumeration caching
     * @return the cache scope
     */
    public DirectoryCacheScope getCacheScope() {
        return cacheScope;
    }

    /**
     * Sets the cache scope for directory enumeration caching
     * @param cacheScope the cache scope to set
     */