public class CallablesTest extends TestCase {

  @J2ktIncompatible // TODO(b/324550390): Enable
  public void testReturning() throws Exception {
    assertThat(Callables.returning(null).call()).isNull();

    Object value = new Object();
    Callable<Object> callable = Callables.returning(value);
    assertSame(value, callable.call());
    // Expect the same value on subsequent calls
    assertSame(value, callable.call());
  }

**FastAPI** provides the same `starlette.responses` as `fastapi.responses` just as a convenience for you, the developer. But most of the available responses come directly from Starlette.

///

## Returning a custom `Response` { #returning-a-custom-response }

5. You can use other standard type annotations with dataclasses as the request body.

    In this case, it's a list of `Item` dataclasses.

6. Here we are returning a dictionary that contains `items` which is a list of dataclasses.

    FastAPI is still capable of <abbr title="converting the data to a format that can be transmitted">serializing</abbr> the data to JSON.

    super.setUp();
    timeLimiter = new FakeTimeLimiter();
  }

  public void testCallWithTimeout_propagatesReturnValue() throws Exception {
    String result =
        timeLimiter.callWithTimeout(Callables.returning(RETURN_VALUE), DELAY_MS, MILLISECONDS);

    assertThat(result).isEqualTo(RETURN_VALUE);
  }

  public void testCallWithTimeout_wrapsCheckedException() throws Exception {

    }

    /**
     * ClassWorld Launcher "enhanced" entry point: returning exitCode and accepts Class World.
     */
    public static int main(String[] args, ClassWorld world) throws IOException {
        return new MavenUpCling(world).run(args, null, null, null, false);
    }

    /**
     * ClassWorld Launcher "embedded" entry point: returning exitCode and accepts Class World and streams.
     */
    public static int main(

   * Invokable<?, Person> factory = Invokable.of(getNameMethod).returning(Person.class);
   * }
   */
  public final <R1 extends R> Invokable<T, R1> returning(Class<R1> returnType) {
    return returning(TypeToken.of(returnType));
  }

  /** Explicitly specifies the return type of this {@code Invokable}. */
  public final <R1 extends R> Invokable<T, R1> returning(TypeToken<R1> returnType) {

        });
    return holder.get();
  }

  /**
   * Updates the value currently associated with {@code key} by combining it with {@code x} via the
   * specified accumulator function, returning the new value. The previous value associated with
   * {@code key} (or zero, if there is none) is passed as the first argument to {@code
   * accumulatorFunction}, and {@code x} is passed as the second argument.
   *

	b.mu.Lock()
	defer b.mu.Unlock()

	// Check if exists already.
	if c, ok := b.caches[o.ID]; ok {
		c.lastHandout = time.Now()
		b.caches[o.ID] = c
		b.debugf("returning existing %v", o.ID)
		return c
	}

	if !o.Create {
		return metacache{
			id:     o.ID,
			bucket: o.Bucket,
			status: scanStateNone,
		}
	}

	// Create new and add.

 *
 * <p>This class maintains a map of nodes to {@link GraphConnections}.
 *
 * <p>Collection-returning accessors return unmodifiable views: the view returned will reflect
 * changes to the graph (if the graph is mutable) but may not be modified by the user.
 *
 * <p>The time complexity of all collection-returning accessors is O(1), since views are returned.
 *
 * @author James Sexton
 * @author Joshua O'Madadhain

      assertEquals(RESULT_VALUE, f.get());
    }
    {
      MockExecutor mock = new MockExecutor();
      TestExecutor testExecutor = new TestExecutor(mock);
      Callable<String> task = Callables.returning(RESULT_VALUE);
      Future<String> f = testExecutor.submit(task);
      mock.assertLastMethodCalled("submit");
      assertEquals(RESULT_VALUE, f.get());
    }
  }