/**
     * Returns the element type if the parameter type of the method is a parameterized {@link Collection}.
     *
     * @param index
     *            The index of the parameter
     * @return The element type if the parameter type is a parameterized {@link Collection}, otherwise {@literal null}
     */
    Class<?> getElementClassOfCollection(int index);

    /**

      warmUp(cache, 0, 100);

      Collection<Object> values = cache.asMap().values();
      values.clear();
      checkEmpty(values);
      checkEmpty(cache);
    }
  }

  public void testValues_empty_remove() {
    for (LoadingCache<Object, Object> cache : caches()) {
      Collection<Object> values = cache.asMap().values();
      assertFalse(values.remove(null));

import com.google.common.annotations.GwtCompatible;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * To be implemented by test generators of things that can contain elements. Such things include
 * both {@link Collection} and {@link Map}; since there isn't an established collective noun that
 * encompasses both of these, 'container' is used.

    }

    /**
     * Get all channels
     *
     * @return collection of all channels
     */
    public Collection<ChannelInfo> getChannels() {
        return channels.values();
    }

    /**
     * Get healthy channels only
     *
     * @return collection of healthy channels
     */
    public Collection<ChannelInfo> getHealthyChannels() {
        return channels.values()

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.AbstractCollectionTester;
import java.util.Queue;
import org.junit.Ignore;

/**
 * Base class for queue collection tests.
 *
 * @author Jared Levy
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.AbstractCollectionTester;
import java.util.Queue;
import org.junit.Ignore;

/**
 * Base class for queue collection tests.
 *
 * @author Jared Levy
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

import java.io.ObjectInputStream;
import java.io.Serializable;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.function.Function;
import java.util.function.ToIntFunction;
import java.util.stream.Collector;
import org.jspecify.annotations.Nullable;

/**

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.util;

import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.codelibs.fess.unit.UnitFessTestCase;

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.core.collection;

import java.util.HashMap;
import java.util.Hashtable;
import java.util.IdentityHashMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.TreeMap;
import java.util.WeakHashMap;

  @CollectionSize.Require(absent = {ZERO, ONE})
  public void testLastIndexOf_duplicate() {
    E[] array = createSamplesArray();
    array[getNumElements() / 2] = e0();
    collection = getSubjectGenerator().create(array);
    assertEquals(
        "lastIndexOf(duplicate) should return index of last occurrence",
        getNumElements() / 2,
        getList().lastIndexOf(e0()));
  }