destIndex = sizeNeeded;
    }
    return new String(dest, 0, destIndex);
  }

  /**
   * Helper method to grow the character buffer as needed, this only happens once in a while so it's
   * ok if it's in a method call. If the index passed in is 0 then no copying will be done.
   */
  private static char[] growBuffer(char[] dest, int index, int size) {

        session.release();

        // Then - Trees should be cleared (we can't directly verify as it's internal,
        // but the cleanup code with synchronized block ensures it happens atomically)
        // The important part is that no exception occurs and the operation is atomic
    }

    /**
     * Test concurrent acquire and release operations.
     */
    @Test

                 * the map to change between that call and this one. But if that happens, the
                 * behavior is undefined because of the concurrent mutation.)
                 *
                 * (Our prototype checker happens to be "smart" enough to understand this for the
                 * *get* call in getValue but not for the *put* call here.)
                 *

        String actualPath = rel.getPath();
        assertNotNull(actualPath, "Path should not be null");
        // Based on the test output, the actual path is "/bar" when parsing relative spec "foo/bar"
        // This happens because the URL class parses "foo" as the host and "/bar" as the path
        assertEquals("/bar", actualPath, "Path should be /bar after URL parsing");

      if (e.getCause() instanceof IllegalArgumentException) {
        /*
         * IllegalArgumentException is the one unchecked exception that we know is likely to happen
         * (thanks to the checkArgument calls in getAnnotatedMethodsNotCached). If it happens, we'd
         * prefer to propagate an IllegalArgumentException to the caller. However, we don't want to

   * WritableByteChannel)}:
   *
   * <ol>
   *   <li>Use sendfile(2) or equivalent. Requires that both the input channel and the output
   *       channel have their own file descriptors. Generally this only happens when both channels
   *       are files or sockets. This performs zero copies - the bytes never enter userspace.
   *   <li>Use mmap(2) or equivalent. Requires that either the input channel or the output channel

  // operation in the constructor.
  //
  // 1. In the listener that performs the callback. In this case it is fine since inputFuture is
  //    assigned prior to calling addListener, and addListener happens-before any invocation of the
  //    listener. Notably, this means that 'volatile' is unnecessary to make 'inputFuture' visible
  //    to the listener.
  //

### Events with Failures

When an operation fails, a failure method is called. This is `connectFailed()` for failures while building a connection to the server, and `callFailed()` when the HTTP call fails permanently. When a failure happens it is possible that a `start` event won’t have a corresponding `end` event.

![Events Diagram](../assets/images/******@****.***)

### Events with Retries and Follow-Ups

    @RetainedLocalRef Future<?> localTimer = timer;
    // Try to cancel the timer as an optimization.
    // timer may be null if this call to run was by the timer task since there is no happens-before
    // edge between the assignment to timer and an execution of the timer task.
    if (localTimer != null) {
      localTimer.cancel(false);
    }

    delegateRef = null;
    timer = null;
  }

[Prometheus](https://prometheus.io) is a cloud-native monitoring platform. Prometheus offers a multi-dimensional data model with time series data identified by metric name and key/value pairs. The data collection happens via a pull model over HTTP/HTTPS. Users looking to monitor their MinIO instances can point Prometheus configuration to scrape data from following endpoints.