*/
    protected final List<ThumbnailGenerator> generatorList = new ArrayList<>();

    /**
     * Queue for thumbnail generation tasks containing URL, content, and path tuples.
     */
    protected BlockingQueue<Tuple3<String, String, String>> thumbnailTaskQueue;

    /**
     * Flag indicating whether thumbnail generation is currently in progress.
     */
    protected volatile boolean generating;

        Tuple3<String, String, String> task = thumbnailGenerator.createTask(null, docMap);
        assertNull(task);
    }

    public void test_createTask_withEmptyPath() {
        // Test task creation with empty path
        Map<String, Object> docMap = new HashMap<>();
        docMap.put("mimetype", "application/pdf");

            private static final long serialVersionUID = 1L;

            @Override
            public Tuple3<String, String, String>[] getVirtualHosts() {
                return new Tuple3[] { new Tuple3<>("Host", "example.com", "site1"), new Tuple3<>("X-Forwarded-Host", "test.com", "site2"),
                        new Tuple3<>("Custom-Header", "custom.value", "site3") };
            }
        });

 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/CollectionUtilitiesExplained#tables">{@code Tables}</a>.
 *
 * @author Jared Levy
 * @author Louis Wasserman
 * @since 7.0
 */
@GwtCompatible
public final class Tables {
  private Tables() {}

  /**
   * Returns a {@link Collector} that accumulates elements into a {@code Table} created using the

import java.nio.file.Files;
import java.nio.file.Path;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.LinkedBlockingQueue;

import org.codelibs.core.misc.Tuple3;
import org.codelibs.fess.Constants;
import org.codelibs.fess.exception.FessSystemException;
import org.codelibs.fess.helper.SystemHelper;
import org.codelibs.fess.mylasta.direction.FessConfig;

  }

  private static Type[] toArray(Collection<Type> types) {
    return types.toArray(new Type[0]);
  }

  private static Iterable<Type> filterUpperBounds(Iterable<Type> bounds) {
    return Iterables.filter(bounds, Predicates.not(Predicates.<Type>equalTo(Object.class)));
  }

  private static void disallowPrimitiveType(Type[] types, String usedAs) {
    for (Type type : types) {
      if (type instanceof Class) {

  }

  private static Type[] toArray(Collection<Type> types) {
    return types.toArray(new Type[0]);
  }

  private static Iterable<Type> filterUpperBounds(Iterable<Type> bounds) {
    return Iterables.filter(bounds, Predicates.not(Predicates.<Type>equalTo(Object.class)));
  }

  private static void disallowPrimitiveType(Type[] types, String usedAs) {
    for (Type type : types) {
      if (type instanceof Class) {

        final Tuple3<String, String, String> task = new Tuple3<>(getName(), thumbnailId, path);
        if (logger.isDebugEnabled()) {
            logger.debug("Create thumbnail task: {}", task);
        }
        return task;
    }

    /**
     * Generates a thumbnail image and saves it to the specified output file.
     *

    }

    @Override
    public Tuple3<String, String, String> createTask(final String path, final Map<String, Object> docMap) {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final String thumbnailId = DocumentUtil.getValue(docMap, fessConfig.getIndexFieldId(), String.class);
        final Tuple3<String, String, String> task = new Tuple3<>(getName(), thumbnailId, path);

 * errors for using {@code get(Comparator.class)} as a {@code Comparator<Foo>}, for example.
 * Immutable empty instances are returned for collection types; {@code ""} for string; {@code 0} for
 * number types; reasonable default instance for other stateless types. For mutable types, a fresh
 * instance is created each time {@code get()} is called.
 *
 * @author Kevin Bourrillion
 * @author Ben Yu
 * @since 12.0
 */