responseData.addMetaData("key1", "value1");
        responseData.addMetaData("key2", 123);

        // Execute - should not throw any exception
        processor.process(responseData);

        // Verify metadata is unchanged
        assertEquals(2, responseData.getMetaDataMap().size());
        assertEquals("value1", responseData.getMetaDataMap().get("key1"));

    checkNotNull(value2);
    checkArgument(!Objects.equals(value1, value2), "Duplicate value provided.");
    distinctValues.replaceValues(type, ImmutableList.of(value1, value2));
    setDefault(type, value1);
    return this;
  }

  /**
   * Tests that {@code cls} properly checks null on all constructor and method parameters that
   * aren't annotated nullable (according to the rules of {@link NullPointerTester}). In details:
   *

    public void test_getFieldValues() throws Exception {
        Map<String, Object> document = new HashMap<>();
        document.put("string_field", "value1");
        document.put("string_array_field", new String[] { "value2", "value3" });
        document.put("list_field", java.util.Arrays.asList("value4", "value5"));
        document.put("int_field", 123);

        String[] stringValues = defaultContentsParser.getFieldValues(document, "string_field");

        return values;
    }

    /**
     * Returns a string representation of this RequestParameter.
     * The format includes the parameter name and its values in array format.
     *
     * @return a string representation of this object in the format "[name, [value1, value2, ...]]"
     */
    @Override
    public String toString() {
        return "[" + name + ", " + Arrays.toString(values) + "]";
    }

          DeferredCloser closer,
          @ParametricNullness V1 value1,
          @ParametricNullness V2 value2,
          @ParametricNullness V3 value3,
          @ParametricNullness V4 value4,
          @ParametricNullness V5 value5)
          throws Exception;
    }

    /**
     * A function that returns a {@link ClosingFuture} when applied to the values of the five

    }

    @Test
    public void testParamMethod() {
        CurlRequest request = new CurlRequest(Method.GET, "https://example.com");

        CurlRequest result = request.param("key1", "value1").param("key2", "value2");

        assertSame(request, result); // Fluent API
    }

    @Test
    public void testParamWithNullValue() {
        CurlRequest request = new CurlRequest(Method.GET, "https://example.com");

        });
  }

  public void testFinishToFuture_preventsFurtherDerivation() {
    ClosingFuture<String> closingFuture = ClosingFuture.from(immediateFuture("value1"));
    FluentFuture<String> unused = closingFuture.finishToFuture();
    assertDerivingThrowsIllegalStateException(closingFuture);
  }

  @Override

  /**
   * Sets two distinct values for {@code type}. These values can be used for both null pointer
   * testing and equals testing.
   *
   * @since 17.0
   */
  protected final <T> void setDistinctValues(Class<T> type, T value1, T value2) {
    tester.setDistinctValues(type, value1, value2);
  }

  /** Specifies that classes that satisfy the given predicate aren't tested for sanity. */

  /**
   * Sets two distinct values for {@code type}. These values can be used for both null pointer
   * testing and equals testing.
   *
   * @since 17.0
   */
  protected final <T> void setDistinctValues(Class<T> type, T value1, T value2) {
    tester.setDistinctValues(type, value1, value2);
  }

  /** Specifies that classes that satisfy the given predicate aren't tested for sanity. */

        assertTrue(result);

        // Verify deletion
        client.admin().indices().prepareRefresh(TEST_INDEX).execute().actionGet();
        long count = client.prepareSearch(TEST_INDEX)
                .setQuery(QueryBuilders.termQuery("field", "value1"))
                .execute()
                .actionGet()
                .getHits()