map.putAll(m);
        assertThat(map.get("THREE"), is("3"));
        assertThat(map.get("FOUR"), is("4"));
        assertThat(map.size(), is(4));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testPerformance() throws Exception {
        for (int j = 0; j < 3; ++j) {
            final int num = 100000;
            final Map<String, String> hmap = new HashMap<String, String>();

import com.google.common.collect.Maps;
import com.google.common.testing.NullPointerTester;
import java.io.IOException;
import java.util.Arrays;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import junit.framework.AssertionFailedError;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Unit test for {@link Joiner}.

import com.google.common.collect.Maps;
import com.google.common.testing.NullPointerTester;
import java.io.IOException;
import java.util.Arrays;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import junit.framework.AssertionFailedError;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Unit test for {@link Joiner}.

    Map<String, Long> in = ImmutableMap.of("1", 1L, "2", 2L, "3", 3L);
    AtomicLongMap<String> map = AtomicLongMap.create();
    assertTrue(map.isEmpty());
    assertEquals(0, map.size());
    assertFalse(map.containsKey("1"));
    assertFalse(map.containsKey("2"));
    assertFalse(map.containsKey("3"));
    assertEquals(0L, map.get("1"));
    assertEquals(0L, map.get("2"));
    assertEquals(0L, map.get("3"));

    map.putAll(in);

    Map<Integer, String> map = CompactLinkedHashMap.create();
    map.put(1, "a");
    map.put(4, "b");
    map.put(3, "d");
    map.put(2, "c");
    map.remove(4);
    testHasMapEntriesInOrder(map, 1, "a", 3, "d", 2, "c");
  }

  public void testInsertionOrderAfterRemoveLastEntry() {
    Map<Integer, String> map = CompactLinkedHashMap.create();
    map.put(1, "a");
    map.put(4, "b");
    map.put(3, "d");

  }

  public void testTransformSingletonMapEquality() {
    Map<String, String> map =
        Maps.transformValues(ImmutableMap.of("a", 1), Functions.toStringFunction());
    Map<String, String> expected = ImmutableMap.of("a", "1");
    assertMapsEqual(expected, map);
    assertEquals(expected.get("a"), map.get("a"));
  }

  public void testTransformIdentityFunctionEquality() {

        assertThat(map.isEmpty(), is(false));
        assertThat(map.get(Foo.class.getTypeParameters()[0]), is(sameClass(Object.class)));
    }

    /**
     * @throws Exception
     */
    public void testGenericMethod() throws Exception {
        final Map<TypeVariable<?>, Type> map = GenericsUtil.getTypeVariableMap(Fuga.class);
        assertThat(map, is(notNullValue()));
        assertThat(map.isEmpty(), is(true));

            return buckets.stream().map(e -> {
                final Map<String, Object> map = new HashMap<>();
                map.put(ID, Base64.getUrlEncoder().encodeToString(e.getKeyAsString().getBytes(StandardCharsets.UTF_8)));
                map.put(KEY, e.getKeyAsString());
                map.put(COUNT, e.getDocCount());
                return map;
            }).collect(Collectors.toList());

        return new ConcurrentHashMap<>(map);
      }
    },
    ImmutableMapImpl {
      @Override
      public <K extends Comparable<K>, V> Map<K, V> create(Map<K, V> map) {
        return ImmutableMap.copyOf(map);
      }
    },
    MapMakerStrongKeysStrongValues {
      @Override
      public <K extends Comparable<K>, V> Map<K, V> create(Map<K, V> map) {

        return new ConcurrentHashMap<>(map);
      }
    },
    ImmutableMapImpl {
      @Override
      public <K extends Comparable<K>, V> Map<K, V> create(Map<K, V> map) {
        return ImmutableMap.copyOf(map);
      }
    },
    MapMakerStrongKeysStrongValues {
      @Override
      public <K extends Comparable<K>, V> Map<K, V> create(Map<K, V> map) {