@GwtCompatible
public abstract class ForwardingMapEntry<K extends @Nullable Object, V extends @Nullable Object>
    extends ForwardingObject implements Map.Entry<K, V> {
  // TODO(lowasser): identify places where thread safety is actually lost

  /** Constructor for use by subclasses. */
  protected ForwardingMapEntry() {}

  @Override
  protected abstract Entry<K, V> delegate();

  @Override
  @ParametricNullness
  public K getKey() {

 * possible sequences of these operations, up to a given number of steps. So, if the caller
 * specifies to use <i>n</i> steps, a total of <i>3^n</i> tests are actually performed.
 *
 * <p>For instance, if <i>steps</i> is 5, one example sequence that will be tested is:
 *
 * <ol>
 *   <li>remove();
 *   <li>hasNext()
 *   <li>hasNext();
 *   <li>remove();
 *   <li>next();

        registration.updateHeartbeat();

        // After update, should not be expired with long timeout
        assertFalse(registration.isExpired(60000));

        // Verify heartbeat was actually updated
        assertTrue(registration.getLastHeartbeat() > initialTime);
    }

    @Test
    void testExpiration() throws InterruptedException {

        super(config);
        this.outputBuffer = outputBuffer;
        this.outputBufferOffset = outputBufferOffset;
    }

    /**
     * Gets the number of bytes actually read
     *
     * @return the dataLength
     */
    public int getDataLength() {
        return this.dataLength;
    }

    /**
     * Gets the number of bytes remaining to be read
     *

     * accessor types to resolve the value for each successive expression part.
     * Finally, return the result of the last expression part's resolution.</p>
     *
     * <p><b>NOTE:</b> The object-graph navigation actually takes place via the
     * {@link ReflectionValueExtractor} class.</p>
     */
    @Override
    public Object getValue(String expression) {
        if (expression == null || expression.trim().isEmpty()) {

import org.gradle.tooling.events.task.TaskSuccessResult
import java.io.Serializable
import java.util.concurrent.atomic.AtomicBoolean

/**
 * Register a build service that monitors a list of tasks and reports CACHE_MISS if they're actually executed.
 */
if (buildCacheEnabled()) {
    registerBuildScanInfoCollectingService(CacheMissMonitorBuildService::class.java, ::isCacheMissMonitoredTask) { gradleRootProject, cacheMissInBuildLogic, cacheMissInMainBuild ->

It is also built to work as a future reference so you can come back and see exactly what you need.

## Run the code { #run-the-code }

All the code blocks can be copied and used directly (they are actually tested Python files).

To run any of the examples, copy the code to a file `main.py`, and start `fastapi dev` with:

<div class="termy">

```console

   * RateLimiter being unused, we increase storedPermits by 1. Say we leave the RateLimiter unused
   * for 10 seconds (i.e., we expected a request at time X, but we are at time X + 10 seconds before
   * a request actually arrives; this is also related to the point made in the last paragraph), thus
   * storedPermits becomes 10.0 (assuming maxStoredPermits >= 10.0). At that point, a request of

And of course, it supports the same:

* data validation
* data serialization
* data documentation, etc.

This works the same way as with Pydantic models. And it is actually achieved in the same way underneath, using Pydantic.

/// info

Keep in mind that dataclasses can't do everything Pydantic models can do.

So, you might still need to use Pydantic models.

```Python
from unicorn import UnicornMiddleware

app = SomeASGIApp()

new_app = UnicornMiddleware(app, some_config="rainbow")
```

But FastAPI (actually Starlette) provides a simpler way to do it that makes sure that the internal middlewares handle server errors and custom exception handlers work properly.

For that, you use `app.add_middleware()` (as in the example for CORS).