import java.util.stream.LongStream;

/**
 * A mutable object which accumulates double values and tracks some basic statistics over all the
 * values added so far. The values may be added singly or in groups. This class is not thread safe.
 *
 * @author Pete Gillin
 * @author Kevin Bourrillion
 * @since 20.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class StatsAccumulator {
  /** Creates a new accumulator. */

 * }
 *
 * <p>Instances of {@link ImmutableValueGraph} do not implement {@link MutableValueGraph}
 * (obviously!) and are contractually guaranteed to be unmodifiable and thread-safe.
 *
 * <p>The Guava User Guide has <a
 * href="https://github.com/google/guava/wiki/GraphsExplained#building-graph-instances">more
 * information on (and examples of) building graphs</a>.
 *

        assertEquals(5, bytesRead);
        for (int i = 0; i < 5; i++) {
            assertEquals(data[i], buffer[i]);
        }
    }

    @Test
    @DisplayName("readn should handle partial reads")
    void testReadnPartial() throws IOException {
        byte[] buffer = new byte[10];
        byte[] data = { 1, 2, 3 };
        ByteArrayInputStream bais = new ByteArrayInputStream(data);

Mabel, I'll stay down here!  It'll be no use their putting their
heads down and saying "Come up again, dear!"  I shall only look
up and say "Who am I then?  Tell me that first, and then, if I
like being that person, I'll come up:  if not, I'll stay down
here till I'm somebody else"--but, oh dear!' cried Alice, with a
sudden burst of tears, `I do wish they WOULD put their heads
down!  I am so VERY tired of being all alone here!'

     * Retrieves an XPathAPI instance from the cache or creates a new one.
     * @return An XPathAPI instance.
     */
    protected XPathAPI getXPathAPI() {
        try {
            return xpathAPICache.get(Thread.currentThread().getName());
        } catch (final ExecutionException e) {
            if (logger.isDebugEnabled()) {
                logger.debug("Failed to retrieval a cache.", e);
            }

	dial   ConnDialer
	authFn AuthFn

	handleMsgWg sync.WaitGroup

	// connChange will be signaled whenever State has been updated, or at regular intervals.
	// Holding the lock allows safe reads of State, and guarantees that changes will be detected.
	connChange *sync.Cond
	handlers   *handlers

	remote             *RemoteClient
	clientPingInterval time.Duration
	connPingInterval   time.Duration

}
```

## 9. Performance Considerations

### 9.1 Memory Management
- Lease entries should be evicted based on LRU when max leases reached
- Implement periodic cleanup of expired leases

### 9.2 Thread Safety
- Use concurrent data structures for lease storage
- Minimize lock contention in hot paths
- Async handling of lease breaks

### 9.3 Network Efficiency
- Batch lease requests when possible

                            // Transform operation
                            ResponseData responseData = new ResponseData();
                            responseData.setUrl("http://thread" + threadId + ".com/page" + j);
                            ResultData resultData = transformer.transform(responseData);

* Add docs for correctly [using FastAPI with Peewee ORM](https://fastapi.tiangolo.com/advanced/sql-databases-peewee/). Including how to overwrite parts of Peewee to correctly handle async threads. PR [#789](https://github.com/tiangolo/fastapi/pull/789).

## 0.45.0

* Add support for OpenAPI Callbacks:
    * New docs: [OpenAPI Callbacks](https://fastapi.tiangolo.com/advanced/openapi-callbacks/).

          }

          System.out.println(response.body().string());
        }
      }
    ```

### Asynchronous Get ([.kt][AsynchronousGetKotlin], [.java][AsynchronousGetJava])

Download a file on a worker thread, and get called back when the response is readable. The callback is made after the response headers are ready. Reading the response body may still block. OkHttp doesn't currently offer asynchronous APIs to receive a response body in parts.