uq.setParentUrl(url);
                    uq.setSessionId(crawlerContext.sessionId);
                    uq.setUrl(d.getUrl());
                    uq.setWeight(d.getWeight());
                    return uq;
                })
                .collect(Collectors.toList());
        urlQueueService.offerAll(crawlerContext.sessionId, childList);
    }

    /**

                }
                throw new ExtractException("Failed to extract the content using available extractors.");
            }

            @Override
            public int getWeight() {
                return extractors[0].getWeight();
            }
        };
    }

    /**
     * Retrieves all extractors for the specified key.
     * @param key The key associated with the extractors.

    }

    /**
     * Gets the weight/priority of this request.
     * @return the weight
     */
    public float getWeight() {
        return weight;
    }

    /**
     * Sets the weight/priority of this request.
     * @param weight the weight
     */
    public void setWeight(float weight) {
        this.weight = weight;
    }

    /**
     * Returns the hash code for this RequestData.

     */
    @Override
    public void setLastModified(final Long lastModified) {
        this.lastModified = lastModified;
    }

    @Override
    public float getWeight() {
        return weight;
    }

    @Override
    public void setWeight(float weight) {
        this.weight = weight;
    }

    /**
     * Returns a string representation of this object.
     * @return A string representation.

                    uq.setParentUrl(url);
                    uq.setSessionId(crawlerContext.getSessionId());
                    uq.setUrl(d.getUrl());
                    uq.setWeight(d.getWeight());
                    return uq;
                })
                .collect(Collectors.toList());

        if (!childList.isEmpty()) {

            return null;
        }

        @Override
        public void setSessionId(String sessionId) {
        }

        @Override
        public void setWeight(float weight) {
        }

        @Override
        public float getWeight() {
            return 0.0f;
        }

        @Override
        public void setCreateTime(Long createTime) {
        }

        @Override

                        // head method
                        responseData =
                                client.execute(RequestDataBuilder.newRequestData().head().url(url).weight(urlQueue.getWeight()).build());
                        if (responseData == null) {
                            return true;
                        }

      return new DummyValueReference<>();
    }

    @Override
    public V get() {
      return value;
    }

    @Override
    public int getWeight() {
      return 1;
    }

    @Override
    public @Nullable ReferenceEntry<K, V> getEntry() {
      return null;
    }

    @Override
    public ValueReference<K, V> copyFor(

        BufferedImage img = ImageIO.read(file);
        logger.debug("width: {}, height: {}", img.getWidth(), img.getHeight());
        assertEquals("Image Width", width, img.getWidth());
        assertEquals("Image Height", height, img.getHeight());
    }

                .modifier(FieldValueFactorFunction.Modifier.LOG2P)
                .setWeight(1.0F)));
        flist.add(new FunctionScoreQueryBuilder.FilterFunctionBuilder(ScoreFunctionBuilders.fieldValueFactorFunction(FieldNames.QUERY_FREQ)
                .missing(0.1f)
                .modifier(FieldValueFactorFunction.Modifier.LOG2P)
                .setWeight(1.0F)));
        flist.add(new FunctionScoreQueryBuilder.FilterFunctionBuilder(