Here’s a [sample event listener](https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/PrintEventsNonConcurrent.java) that prints each event with a timestamp.

```java
class PrintingEventListener extends EventListener {
  private long callStartNanos;

  private void printEvent(String name) {
    long nowNanos = System.nanoTime();
    if (name.equals("callStart")) {

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class CollectionRetainAllTester<E> extends AbstractCollectionTester<E> {

  /** A collection of elements to retain, along with a description for use in failure messages. */
  private final class Target {
    private final Collection<E> toRetain;
    private final String description;

 */

package com.google.common.collect;

import com.google.common.annotations.GwtCompatible;

/**
 * Unused stub class, unreferenced under Java and manually emulated under GWT.
 *
 * @author Chris Povirk
 */
@GwtCompatible
abstract class ForwardingImmutableList<E> {
  private ForwardingImmutableList() {}

 * limitations under the License.
 */

package gradlebuild.binarycompatibility.sources

sealed interface SinceTagStatus {
    data class Present(val version: String): SinceTagStatus
    data object NotNeeded: SinceTagStatus
    data class Inconsistent(val versions: List<String?>): SinceTagStatus
    data object Missing: SinceTagStatus

### Crear una clase `Enum` { #create-an-enum-class }

Importa `Enum` y crea una subclase que herede de `str` y de `Enum`.

Al heredar de `str`, la documentación de la API podrá saber que los valores deben ser de tipo `string` y podrá representarlos correctamente.

Luego crea atributos de clase con valores fijos, que serán los valores válidos disponibles:

 * }
 * public void testFooLeak() {
 *   GcFinalization.awaitClear(fooWeakRef());
 * }
 * }
 *
 * <p>This class cannot currently be used to test soft references, since this class does not try to
 * create the memory pressure required to cause soft references to be cleared.
 *
 * <p>This class only provides testing utilities. It is not designed for direct use in production or
 * for benchmarking.
 *

package common

enum class FlakyTestStrategy {
    INCLUDE,
    EXCLUDE,
    ONLY,
    ;

    override fun toString() = name.lowercase()

from typing_extensions import Literal, deprecated

from ._compat import (
    Undefined,
)

_Unset: Any = Undefined


class ParamTypes(Enum):
    query = "query"
    header = "header"
    path = "path"
    cookie = "cookie"


class Param(FieldInfo):  # type: ignore[misc]
    in_: ParamTypes

    def __init__(
        self,
        default: Any = Undefined,
        *,

/**
 * Test class for Lmhosts
 */
class LmhostsTest {

    private Lmhosts lmhosts;
    private CIFSContext mockContext;
    private Configuration mockConfig;

    @TempDir
    Path tempDir;

    @BeforeEach
    void setUp() {
        lmhosts = new Lmhosts();
        mockContext = mock(CIFSContext.class);
        mockConfig = mock(Configuration.class);

<div class="termy">

```console
$ pip install "fastapi[all]"
---> 100%
```

</div>

### Create the `Settings` object { #create-the-settings-object }

Import `BaseSettings` from Pydantic and create a sub-class, very much like with a Pydantic model.

The same way as with Pydantic models, you declare class attributes with type annotations, and possibly default values.