public void test_saveImage() throws Exception {
        HtmlTagBasedGenerator generator = new HtmlTagBasedGenerator();
        ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
        File outputFile = File.createTempFile("generator_", ".png");

        String imagePath = "thumbnail/600x400.png";

    private final OneSizeTestContainerGenerator<BiMap<K, V>, Entry<K, V>> generator;

    public MapGenerator(
        OneSizeTestContainerGenerator<BiMap<K, V>, Entry<K, V>> oneSizeTestContainerGenerator) {
      this.generator = oneSizeTestContainerGenerator;
    }

    @Override
    public SampleElements<Entry<K, V>> samples() {
      return generator.samples();
    }

    @Override

import com.google.common.annotations.GwtCompatible;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * To be implemented by test generators that can produce test subjects without requiring any
 * parameters.
 *
 * @param <T> the type created by this generator.
 * @author George van den Driessche
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestSubjectGenerator<T extends @Nullable Object> {

import com.google.common.annotations.GwtCompatible;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import org.checkerframework.checker.nullness.qual.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.
 *

import com.google.common.annotations.GwtCompatible;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import org.checkerframework.checker.nullness.qual.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.
 *

    private final OneSizeTestContainerGenerator<BiMap<K, V>, Entry<K, V>> generator;

    public MapGenerator(
        OneSizeTestContainerGenerator<BiMap<K, V>, Entry<K, V>> oneSizeTestContainerGenerator) {
      this.generator = oneSizeTestContainerGenerator;
    }

    @Override
    public SampleElements<Entry<K, V>> samples() {
      return generator.samples();
    }

    @Override

        } else {
          // Cannot use empty generator. Proceed with other generators.
        }
      } else {
        // never generated empty instance for this type before.
        Object emptyInstance = invokeGeneratorMethod(emptyGenerate);
        emptyInstanceGenerated.put(type.getType(), freshness.get());
        return emptyInstance;
      }
    }
    Method generate = GENERATORS.get(rawType);
    if (generate != null) {

import com.google.common.annotations.GwtCompatible;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * To be implemented by test generators that can produce test subjects without requiring any
 * parameters.
 *
 * @param <T> the type created by this generator.
 * @author George van den Driessche
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestSubjectGenerator<T extends @Nullable Object> {

          OneSizeTestContainerGenerator<Map<K, V>, Entry<K, V>> mapGenerator) {
    TestContainerGenerator<Map<K, V>, Entry<K, V>> generator = mapGenerator.getInnerGenerator();
    if (generator instanceof TestSortedMapGenerator
        && ((TestSortedMapGenerator<K, V>) generator).create().keySet() instanceof SortedSet) {
      return new MapSortedKeySetGenerator<>(mapGenerator);
    } else {

import com.google.common.collect.testing.UnhashableObject;
import java.util.Collection;
import java.util.EnumMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

/**
 * Generators of different types of map and related collections, such as keys, entries and values.
 *
 * @author Hayward Chan
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public class MapGenerators {