// Test SearchEngineClient field injection
        ThumbnailGenerator generator = new ThumbnailGenerator();
        assertNull(generator.searchEngineClient);

        // After proper initialization, it should be injected
        SearchEngineClient mockClient = new SearchEngineClient() {
            // Mock implementation
        };
        generator.searchEngineClient = mockClient;

        StopwordsItem item2 = new StopwordsItem(1, "test");

        item1.setNewInput("updated");
        item2.setNewInput("different");

        // Should still be equal based on original input
        assertTrue(item1.equals(item2));
    }

    public void test_toString() {
        // Test toString method
        StopwordsItem item = new StopwordsItem(123, "word");

import java.util.Collections;
import java.util.List;
import java.util.Map.Entry;
import java.util.NavigableMap;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests operations on a NavigableMap. Can't be invoked directly; please
 * see {@code NavigableMapTestSuiteBuilder}.
 *
 * @author Jesse Wilson
 * @author Louis Wasserman
 */
@GwtIncompatible

 * invoke methods, they invoke methods on the {@code ForwardingList}.
 *
 * <p>The {@code standard} methods and any collection views they return are not guaranteed to be
 * thread-safe, even when all of the methods that they depend on are thread-safe.
 *
 * @author Mike Bostock
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible

 * invoke methods, they invoke methods on the {@code ForwardingSortedMultiset}.
 *
 * <p>The {@code standard} methods and any collection views they return are not guaranteed to be
 * thread-safe, even when all of the methods that they depend on are thread-safe.
 *
 * @author Louis Wasserman
 * @since 15.0
 */
@GwtCompatible

import java.util.Collections;
import java.util.List;
import java.util.Map.Entry;
import java.util.NavigableMap;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests operations on a NavigableMap. Can't be invoked directly; please
 * see {@code NavigableMapTestSuiteBuilder}.
 *
 * @author Jesse Wilson
 * @author Louis Wasserman
 */
@GwtIncompatible

   * will typically have been set to an appropriate loader for the current thread.
   *
   * <p>In the unusual case where the context class loader is null, the class loader that loaded
   * this class ({@code Resources}) will be used instead.
   *
   * @throws IllegalArgumentException if the resource is not found
   */
  @CanIgnoreReturnValue // being used to check if a resource exists

 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *

 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *

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

import jakarta.annotation.Resource;

/**
 * Implementation of the {@link UrlQueueService} interface.
 * This class provides methods for managing a queue of URLs to be crawled,
 * including adding, deleting, and retrieving URLs from the queue.
 * It uses a {@link MemoryDataHelper} to store the URL queue data in memory.
 *
 * <p>
 * The class is responsible for:
 * </p>
 * <ul>