public class MapClearTester<K, V> extends AbstractMapTester<K, V> {
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testClear() {
    getMap().clear();
    assertTrue("After clear(), a map should be empty.", getMap().isEmpty());
    assertEquals(0, getMap().size());
    assertFalse(getMap().entrySet().iterator().hasNext());
  }

  public void testClearClearsInverse() {
    BiMap<V, K> inv = getMap().inverse();
    getMap().clear();
    assertTrue(getMap().isEmpty());
    assertTrue(inv.isEmpty());
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testKeySetClearClearsInverse() {
    BiMap<V, K> inv = getMap().inverse();
    getMap().keySet().clear();
    assertTrue(getMap().isEmpty());
    assertTrue(inv.isEmpty());
  }

    return (row == null) ? null : Maps.safeGet(row, columnKey);
  }

  @Override
  public boolean isEmpty() {
    return size() == 0;
  }

  @Override
  public void clear() {
    Iterators.clear(cellSet().iterator());
  }

  @CanIgnoreReturnValue
  @Override
  @CheckForNull
  public V remove(@CheckForNull Object rowKey, @CheckForNull Object columnKey) {

assignees: ''

---

**Is your feature request related to a problem? Please describe.**
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**Describe the solution you'd like**
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**Describe alternatives you've considered**
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**Additional context**

  public void testClear() {
    collection.clear();
    assertTrue("After clear(), a collection should be empty.", collection.isEmpty());
    assertEquals(0, collection.size());
    assertFalse(collection.iterator().hasNext());
  }

  @CollectionFeature.Require(absent = SUPPORTS_REMOVE)
  @CollectionSize.Require(absent = ZERO)
  public void testClear_unsupported() {
    try {
      collection.clear();
      fail(

  public void testClear() {
    multimap().clear();
    assertCleared();
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testClearThroughEntries() {
    multimap().entries().clear();
    assertCleared();
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testClearThroughAsMap() {
    multimap().asMap().clear();
    assertCleared();
  }

  @MapFeature.Require(SUPPORTS_REMOVE)

  public void testClear() {
    multimap().clear();
    assertCleared();
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testClearThroughEntries() {
    multimap().entries().clear();
    assertCleared();
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testClearThroughAsMap() {
    multimap().asMap().clear();
    assertCleared();
  }

  @MapFeature.Require(SUPPORTS_REMOVE)

			appendToRelations(reflectValue.Index(i), reflect.Indirect(reflect.ValueOf(values[i])), clear)

			// TODO support save slice data, sql with case?
			association.Error = associationDB.Updates(reflectValue.Index(i).Addr().Interface()).Error
		}
	case reflect.Struct:
		// clear old data
		if clear && len(values) == 0 {

	// Prepare Data for Clear
	if err := DB.Model(&user2).Association("Languages").Append(&language); err != nil {
		t.Fatalf("Error happened when append Languages, got %v", err)
	}

	AssertAssociationCount(t, user2, "Languages", 1, "after prepare data")

	// Clear
	if err := DB.Model(&user2).Association("Languages").Clear(); err != nil {
		t.Errorf("Error happened when clear Languages, got %v", err)
	}

  public void testClearClearsInverse() {
    BiMap<V, K> inv = getMap().inverse();
    getMap().clear();
    assertTrue(getMap().isEmpty());
    assertTrue(inv.isEmpty());
  }

  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testKeySetClearClearsInverse() {
    BiMap<V, K> inv = getMap().inverse();
    getMap().keySet().clear();
    assertTrue(getMap().isEmpty());
    assertTrue(inv.isEmpty());
  }