# How To - Recipes { #how-to-recipes }

Here you will see different recipes or "how to" guides for **several topics**.

Most of these ideas would be more or less **independent**, and in most cases you should only need to study them if they apply directly to **your project**.

If something seems interesting and useful to your project, go ahead and check it, but otherwise, you might probably just skip them.

/// tip

  public void leave() {
    ReentrantLock lock = this.lock;
    try {
      // No need to signal if we will still be holding the lock when we return
      if (lock.getHoldCount() == 1) {
        signalNextWaiter();
      }
    } finally {
      lock.unlock(); // Will throw IllegalMonitorStateException if not held
    }
  }

  /** Returns whether this monitor is using a fair ordering policy. */

  // https://publicobject.com (Comodo) and https://squareup.com (Entrust). But they aren't
  // sufficient to connect to most HTTPS sites including https://godaddy.com and https://visa.com.
  // Typically developers will need to get a PEM file from their organization's TLS administrator.
  final X509Certificate comodoRsaCertificationAuthority = Certificates.decodeCertificatePem(""
      + "-----BEGIN CERTIFICATE-----\n"

    this.delegate = new ArrayDeque<>(maxSize);
    this.maxSize = maxSize;
  }

  /**
   * Creates and returns a new evicting queue that will hold up to {@code maxSize} elements.
   *
   * <p>When {@code maxSize} is zero, elements will be evicted immediately after being added to the
   * queue.
   */
  public static <E> EvictingQueue<E> create(int maxSize) {
    return new EvictingQueue<>(maxSize);
  }

 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *

// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//

// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//

   * Note that if {@code occurrences == 1}, this is functionally equivalent to the call {@code
   * remove(element)}.
   *
   * @param element the element to conditionally remove occurrences of
   * @param occurrences the number of occurrences of the element to remove. May be zero, in which
   *     case no change will be made.

   * is empty.
   *
   * <p><b>Warning:</b> Typical uses of the resulting iterator may produce an infinite loop. You
   * should use an explicit {@code break} or be certain that you will eventually remove all the
   * elements.
   *
   * <p>To cycle over the iterable {@code n} times, use the following: {@code
   * Iterables.concat(Collections.nCopies(n, iterable))}
   *

These loosely follow the model set in [Google Cloud Policies](https://cloud.google.com/load-balancing/docs/ssl-policies-concepts). We [track changes](../security/tls_configuration_history.md) to this policy.

By default, OkHttp will attempt a `MODERN_TLS` connection.  However by configuring the client connectionSpecs you can allow a fall back to `COMPATIBLE_TLS` connection if the modern configuration fails.

```java