### Multi-Module Structure

```
fess-crawler-parent/
├── fess-crawler/              # Core crawler framework
│   ├── client/               # Protocol clients (HTTP, FTP, SMB, etc.)
│   ├── extractor/           # Content extractors
│   ├── transformer/         # Data transformers
│   └── service/             # Core services
├── fess-crawler-lasta/       # LastaFlute DI integration
└── fess-crawler-opensearch/  # OpenSearch backend

import org.codelibs.fess.crawler.entity.AccessResultImpl;
import org.codelibs.fess.crawler.entity.UrlQueue;
import org.codelibs.fess.crawler.entity.UrlQueueImpl;
import org.codelibs.fess.crawler.extractor.ExtractorFactory;
import org.codelibs.fess.crawler.extractor.impl.TikaExtractor;
import org.codelibs.fess.crawler.filter.impl.UrlFilterImpl;
import org.codelibs.fess.crawler.helper.ContentLengthHelper;
import org.codelibs.fess.crawler.helper.EncodingHelper;

            if (MAX_QUERY_TERM_LENGTH < k.length()) {
                return new String[0];
            }
        }
        return keywords.toArray(new String[keywords.size()]);
    }

    /**
     * Extracts keywords from the given query string based on the specified fields.
     *
     * @param q the query string to parse and extract keywords from
     * @param fields the fields to consider when extracting keywords

// must be extracted from the header.
var userMetadataKeyPrefixes = []string{
	"x-amz-meta-",
	"x-minio-meta-",
}

// extractMetadataFromReq extracts metadata from HTTP header and HTTP queryString.
func extractMetadataFromReq(ctx context.Context, r *http.Request) (metadata map[string]string, err error) {

                }
            } catch (final IOException e) {
                logger.warn("Failed to delete {}", path, e);
            }
        }

        /**
         * Extracts the document ID from a file path.
         *
         * @param file the file path
         * @return the extracted document ID
         */
        protected String getDocId(final Path file) {

*   Delegate application failure leaves interpreter in valid state.
*   Add check for correct memory alignment to
    `MemoryAllocation::MemoryAllocation()`.
*   Extracts `NNAPIDelegateKernel` from nnapi_delegate.cc
*   Added support for `FusedBatchNormV3` in converter.
*   A ragged to dense op for directly calculating tensors.
*   Fix accidental quadratic graph construction cost in graph-mode