assertFalse(thumbnailGenerator.generate(thumbnailId, null));
    }

    public void test_generate_withInvalidOutputPath() throws IOException {
        // Test generation with non-writable output file
        File readOnlyDir = Files.createTempDirectory(tempDir, "readonly").toFile();
        readOnlyDir.setWritable(false);
        File invalidOutputFile = new File(readOnlyDir, "thumbnail.png");

        if (field != null && ModifierUtil.isPublic(field)) {
            readable = true;
            writable = true;
        }
    }

    @Override
    public boolean isReadable() {
        return readable;
    }

    @Override
    public boolean isWritable() {
        return writable;
    }

    @Override
    public <T> T getValue(final Object target) {

import org.dbflute.Entity;
import org.dbflute.bhv.AbstractBehaviorWritable;
import org.dbflute.bhv.readable.EntityRowHandler;
import org.dbflute.bhv.writable.DeleteOption;
import org.dbflute.bhv.writable.InsertOption;
import org.dbflute.bhv.writable.UpdateOption;
import org.dbflute.cbean.ConditionBean;
import org.dbflute.cbean.coption.CursorSelectOption;
import org.dbflute.cbean.result.ListResultBean;

import org.dbflute.Entity;
import org.dbflute.bhv.AbstractBehaviorWritable;
import org.dbflute.bhv.readable.EntityRowHandler;
import org.dbflute.bhv.writable.DeleteOption;
import org.dbflute.bhv.writable.InsertOption;
import org.dbflute.bhv.writable.UpdateOption;
import org.dbflute.cbean.ConditionBean;
import org.dbflute.cbean.coption.CursorSelectOption;
import org.dbflute.cbean.result.ListResultBean;

import org.dbflute.Entity;
import org.dbflute.bhv.AbstractBehaviorWritable;
import org.dbflute.bhv.readable.EntityRowHandler;
import org.dbflute.bhv.writable.DeleteOption;
import org.dbflute.bhv.writable.InsertOption;
import org.dbflute.bhv.writable.UpdateOption;
import org.dbflute.cbean.ConditionBean;
import org.dbflute.cbean.coption.CursorSelectOption;
import org.dbflute.cbean.result.ListResultBean;

  public static <K, V> ImmutableMap<K, V> copyOf(Map<? extends K, ? extends V> map) {
    if ((map instanceof ImmutableMap) && !(map instanceof ImmutableSortedMap)) {
      @SuppressWarnings("unchecked") // safe since map is not writable
      ImmutableMap<K, V> kvMap = (ImmutableMap<K, V>) map;
      return kvMap;
    } else if (map instanceof EnumMap) {
      EnumMap<?, ?> enumMap = (EnumMap<?, ?>) map;

      total += r;
    }
    return total;
  }

  /**
   * Copies all bytes from the readable channel to the writable channel. Does not close or flush
   * either channel.
   *
   * @param from the readable channel to read from
   * @param to the writable channel to write to
   * @return the number of bytes copied
   * @throws IOException if an I/O error occurs
   */
  @J2ktIncompatible

   */
  public static <K, V> ImmutableBiMap<K, V> copyOf(Map<? extends K, ? extends V> map) {
    if (map instanceof ImmutableBiMap) {
      @SuppressWarnings("unchecked") // safe since map is not writable
      ImmutableBiMap<K, V> bimap = (ImmutableBiMap<K, V>) map;
      // TODO(lowasser): if we need to make a copy of a BiMap because the
      // forward map is a view, don't make a copy of the non-view delegate map

    }

    // TODO(lowasser): copy ImmutableSetMultimap by using asList() on the sets
    if (multimap instanceof ImmutableListMultimap) {
      @SuppressWarnings("unchecked") // safe since multimap is not writable
      ImmutableListMultimap<K, V> kvMultimap = (ImmutableListMultimap<K, V>) multimap;
      if (!kvMultimap.isPartialView()) {
        return kvMultimap;
      }
    }

 *
 * @constructor Create a cache which will reside in [directory]. This cache is lazily initialized on
 *     first access and will be created if it does not exist.
 * @param directory a writable directory.
 * @param valueCount the number of values per cache entry. Must be positive.
 * @param maxSize the maximum number of bytes this cache should use to store.
 */
class DiskLruCache(
  fileSystem: FileSystem,