loading.gif...

  /**
   * Returns the value associated with {@code key} in this cache, first loading that value if
   * necessary. No observable state associated with this cache is modified until loading completes.
   *
   * <p>If another call to {@link #get} or {@link #getUnchecked} is currently loading the value for
   * {@code key}, simply waits for that thread to finish and returns its loaded value. Note that

    /**
     * Records the successful load of a new entry. This should be called when a cache request causes
     * an entry to be loaded, and the loading completes successfully. In contrast to {@link
     * #recordMisses}, this method should only be called by the loading thread.
     *
     * @param loadTime the number of nanoseconds the cache spent computing or retrieving the new
     *     value
     */

 *       <ul>
 *         <li>After successfully loading an entry {@code missCount} and {@code loadSuccessCount}
 *             are incremented, and the total loading time, in nanoseconds, is added to {@code
 *             totalLoadTime}.
 *         <li>When an exception is thrown while loading an entry, {@code missCount} and {@code
 *             loadExceptionCount} are incremented, and the total loading time, in nanoseconds, is

 *       <ul>
 *         <li>After successfully loading an entry {@code missCount} and {@code loadSuccessCount}
 *             are incremented, and the total loading time, in nanoseconds, is added to {@code
 *             totalLoadTime}.
 *         <li>When an exception is thrown while loading an entry, {@code missCount} and {@code
 *             loadExceptionCount} are incremented, and the total loading time, in nanoseconds, is

   * it would prevent our class loader from getting garbage collected.
   */
  static class DecoupledLoader implements FinalizerLoader {
    private static final String LOADING_ERROR =
        "Could not load Finalizer in its own class loader. Loading Finalizer in the current class "
            + "loader instead. As a result, you will not be able to garbage collect this class "

   * it would prevent our class loader from getting garbage collected.
   */
  static class DecoupledLoader implements FinalizerLoader {
    private static final String LOADING_ERROR =
        "Could not load Finalizer in its own class loader. Loading Finalizer in the current class "
            + "loader instead. As a result, you will not be able to garbage collect this class "

  /**
   * Returns the value associated with {@code key} in this cache, first loading that value if
   * necessary. No observable state associated with this cache is modified until loading completes.
   *
   * <p>If another call to {@link #get} or {@link #getUnchecked} is currently loading the value for
   * {@code key}, simply waits for that thread to finish and returns its loaded value. Note that

 * of project dependencies. This optimizes module loading during runtime, as we will only load external
 * modules that are not loaded transitively by other project modules.
 *
 * We perform this filtering, since if we simply include all external dependencies, regardless of whether
 * they are already loaded transitively, there is a measurable performance impact during module-loading.
 */

    @CheckForNull
    V get();

    /**
     * Waits for a value that may still be loading. Unlike get(), this method can block (in the case
     * of FutureValueReference).
     *
     * @throws ExecutionException if the loading thread throws an exception
     * @throws ExecutionError if the loading thread throws an error
     */
    V waitForValue() throws ExecutionException;