@CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(ALLOWS_NULL_KEYS)
  public void testEqualsMultimapWithNullKey() {
    Multimap<K, V> original = multimap();
    initMultimapWithNullKey();
    Multimap<K, V> withNull = multimap();
    new EqualsTester()
        .addEqualityGroup(original)
        .addEqualityGroup(
            withNull, getSubjectGenerator().create((Object[]) createArrayWithNullKey()))
        .testEquals();
  }

No quieres que la dependencia original se ejecute (ni ninguna de las sub-dependencias que pueda tener).

En cambio, quieres proporcionar una dependencia diferente que se usará solo durante las pruebas (posiblemente solo algunas pruebas específicas), y que proporcionará un valor que pueda ser usado donde se usó el valor de la dependencia original.

### Casos de uso: servicio externo { #use-cases-external-service }

There are some scenarios where you might want to override a dependency during testing.

You don't want the original dependency to run (nor any of the sub-dependencies it might have).

Instead, you want to provide a different dependency that will be used only during tests (possibly only some specific tests), and will provide a value that can be used where the value of the original dependency was used.

### Use cases: external service { #use-cases-external-service }

    }

    @Test
    public void testHandleGuidRoundTrip() {
        HandleGuid original = new HandleGuid();
        byte[] bytes = original.toBytes();
        HandleGuid reconstructed = new HandleGuid(bytes);

        assertEquals(original, reconstructed);
        assertEquals(original.toString(), reconstructed.toString());
        assertEquals(original.hashCode(), reconstructed.hashCode());
    }

    @Test

    }

    @Override
    public Set<K> keySet() {
        // return original keys
        return parent.keySet();
    }

    @Override
    public Collection<V> values() {
        return parent.values();
    }

    @Override
    public Set<Entry<K, V>> entrySet() {
        // return original keys
        return parent.entrySet();
    }

    @Override

        data[0] = 99;
        assertFalse(original.equals(copy), "After mutation, original should not equal previous clone");

        // Ensure arrays are independent: mutate clone's buffer via getter
        copy.get()[1] = 77;
        assertNotEquals(original.toString(), copy.toString(), "Mutating clone should not affect original");
    }

Você não quer que a dependência original execute (e nenhuma das subdependências que você possa ter).

Em vez disso, você deseja fornecer uma dependência diferente que será usada somente durante os testes (possivelmente apenas para alguns testes específicos) e fornecerá um valor que pode ser usado onde o valor da dependência original foi usado.

### Casos de uso: serviço externo { #use-cases-external-service }

        newOutput = newOutputs;
    }

    /**
     * Gets the original input word.
     *
     * @return The original input word.
     */
    public String getInput() {
        return input;
    }

    /**
     * Gets the original output stem.
     *
     * @return The original output stem.
     */
    public String getOutput() {
        return output;
    }

 * It also tracks updated values for the item.
 */
public class SynonymItem extends DictionaryItem {
    /** The original input words. */
    private final String[] inputs;

    /** The original output synonyms. */
    private final String[] outputs;

    /** The new input words, if updated. */
    private String[] newInputs;

                // The first definition wins.
                Lifecycle original = phaseToLifecycleMap.put(phase, lifecycle);
                if (original != null && logger.isWarnEnabled()) {
                    logger.warn(
                            "Duplicated lifecycle phase {}. Defined in {} but also in {}",
                            phase,
                            original.getId(),
                            lifecycle.getId());