```

### Key Design Patterns

**Factory**: `CrawlerClientFactory`, `ExtractorFactory` - protocol/format-specific component selection
**Strategy**: `CrawlerClient`, `Extractor`, `Transformer` - pluggable implementations
**Builder**: `RequestDataBuilder`, `ExtractorBuilder` - fluent construction
**Template Method**: `AbstractCrawlerClient`, `AbstractExtractor` - common logic with overrides

 */
package org.codelibs.fess.storage;

import java.io.InputStream;
import java.io.OutputStream;
import java.util.List;
import java.util.Map;

/**
 * Interface for cloud storage operations.
 * Implementations provide access to S3-compatible storage, GCS, or other cloud storage systems.
 */
public interface StorageClient extends AutoCloseable {

    /**
     * Uploads an object to storage.
     *

    }

    /**
     * Test that validateInputStream works with various InputStream implementations.
     */
    public void test_validateInputStream_worksWithVariousStreamTypes() {
        // ByteArrayInputStream
        extractor.testValidateInputStream(new ByteArrayInputStream(new byte[10]));

        // Custom InputStream implementation
        final InputStream customStream = new InputStream() {
            @Override

│   └── exentity/              # Extended entities (domain models)
├── helper/                    # Cross-cutting utilities
├── crawler/                   # Crawling engine
├── sso/                       # SSO implementations
└── ds/                        # Data store connectors

src/main/resources/
├── fess_config.properties     # Main config
├── app.xml                    # DI configuration

import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

/**
 * Factory class responsible for managing and providing access to data store instances.
 * This factory maintains a registry of data store implementations and provides methods
 * to register, retrieve, and discover available data stores.
 *
 * <p>Data stores are registered by name and class name, allowing flexible lookup.

                  }
                })
            .named(
                "ForwardingNavigableMap[SafeTreeMap] with no comparator and standard "
                    + "implementations")
            .withFeatures(
                CollectionSize.ANY,
                CollectionFeature.KNOWN_ORDER,
                MapFeature.ALLOWS_NULL_VALUES,

import org.codelibs.fess.crawler.exception.ExtractException;
import org.dbflute.utflute.core.PlainTestCase;

/**
 * Test class to verify proper resource management in Extractor implementations.
 * This test ensures that resources are properly closed even when exceptions occur.
 */
public class ExtractorResourceManagementTest extends PlainTestCase {

    throw new UnsupportedOperationException();
  }

  /**
   * Returns {@code true} if this immutable multimap's implementation contains references to
   * user-created objects that aren't accessible via this multimap's methods. This is generally used
   * to determine whether {@code copyOf} implementations should make an explicit copy to avoid
   * memory leaks.
   */
  boolean isPartialView() {
    return map.isPartialView();

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentSkipListMap;
import junit.framework.Test;
import junit.framework.TestSuite;

/**
 * Generates a test suite covering the {@link Map} implementations in the {@link java.util} package.
 * Can be subclassed to specify tests that should be suppressed.
 *
 * @author Kevin Bourrillion
 */
@GwtIncompatible
public class TestsForMapsInJavaUtil {

import org.codelibs.fess.util.ComponentUtil;
import org.codelibs.fess.util.DocumentUtil;

/**
 * Abstract base class for thumbnail generators.
 * Provides common functionality for thumbnail generation implementations.
 */
public abstract class BaseThumbnailGenerator implements ThumbnailGenerator {
    private static final Logger logger = LogManager.getLogger(BaseThumbnailGenerator.class);