* building for Android): Ensure that any object you pass implements the interface not just in
     * your current SDK version but also at the oldest version you support. For example, <a
     * href="https://developer.android.com/sdk/api_diff/16/">API Level 16</a> is the first version
     * in which {@code Cursor} is {@code Closeable}. To support older versions, pass a wrapper

   * nullness checker can already "prove" are non-null. That means that the first parameter to
   * checkNotNull *should* be annotated to require it to be non-null.
   *
   * However, for a variety of reasons, Google developers have written a ton of code over the past
   * decade that assumes that they can use checkNotNull for non-precondition checks. I had hoped to

 * work during upgrades. However it is generally inadvisable for <i>libraries</i> (which get
 * included on users' CLASSPATHs, outside the library developers' control) to do so.
 *
 * @author Kevin Bourrillion
 */
@Retention(RetentionPolicy.CLASS)
@Target({
  ElementType.ANNOTATION_TYPE,
  ElementType.CONSTRUCTOR,
  ElementType.FIELD,
  ElementType.METHOD,

 *       annotations in Guava. Or you might prefer to omit Guava from your {@code AnnotatedPackages}
 *       list.
 *   <li><a href="https://developers.google.com/j2objc">J2ObjC</a>
 *   <li>{@code NullPointerTester}, at least in the Android backport (where the type-use annotations
 *       {@code NullPointerTester} would need are not available) and in case of <a

 *       annotations in Guava. Or you might prefer to omit Guava from your {@code AnnotatedPackages}
 *       list.
 *   <li><a href="https://developers.google.com/j2objc">J2ObjC</a>
 *   <li>{@code NullPointerTester}, at least in the Android backport (where the type-use annotations
 *       {@code NullPointerTester} would need are not available) and in case of <a

 * `-android` "flavors.")
 *
 * (We could consider releasing a listenablefuture:1.0.1 someday. But we would want to look into how
 * that affects users, especially users of the Android Gradle Plugin, since the plugin developers
 * put in a special hack for us: https://issuetracker.google.com/issues/131431257)
 */
@DoNotMock("Use the methods in Futures (like immediateFuture) or SettableFuture")
@ElementTypesAreNonnullByDefault

  /**
   * The Google API KEY for OkHttp recipes. If you're using Google APIs for anything other than
   * running these examples, please request your own client ID!
   *
   * https://console.developers.google.com/project
   */
  public static final String GOOGLE_API_KEY = "AIzaSyAx2WZYe0My0i-uGurpvraYJxO7XNbwiGs";
  public static final MediaType MEDIA_TYPE_JSON = MediaType.get("application/json");

 *       annotations in Guava. Or you might prefer to omit Guava from your {@code AnnotatedPackages}
 *       list.
 *   <li><a href="https://developers.google.com/j2objc">J2ObjC</a>
 *   <li>{@code NullPointerTester}, at least in the Android backport (where the type-use annotations
 *       {@code NullPointerTester} would need are not available) and in case of <a

 *       annotations in Guava. Or you might prefer to omit Guava from your {@code AnnotatedPackages}
 *       list.
 *   <li><a href="https://developers.google.com/j2objc">J2ObjC</a>
 *   <li>{@code NullPointerTester}, at least in the Android backport (where the type-use annotations
 *       {@code NullPointerTester} would need are not available) and in case of <a

 *       annotations in Guava. Or you might prefer to omit Guava from your {@code AnnotatedPackages}
 *       list.
 *   <li><a href="https://developers.google.com/j2objc">J2ObjC</a>
 *   <li>{@code NullPointerTester}, at least in the Android backport (where the type-use annotations
 *       {@code NullPointerTester} would need are not available) and in case of <a