*   <li>In at least one case, a use of {@code sun.misc.FpUtils}, the test will not even
 *       <i>compile</i> against Android. Now, this might be an artifact of our build system, one
 *       that we could probably work around. Or we could manually strip the test from open-source
 *       Guava while continuing to run it internally, as we do with many other tests. This would

  }

  @Benchmark
  public int collapseFrom(int reps) {
    int result = 0;
    CharMatcher matcher = this.matcher;
    String teststring = this.teststring;
    for (int i = 0; i < reps; i++) {
      result += System.identityHashCode(matcher.collapseFrom(teststring, ' '));
    }
    return result;
  }

  private static String allMatchingChars(BitSet bitSet) {
    final char[] result = new char[bitSet.cardinality()];

    out.write(data);
    assertTrue(Arrays.equals(data, source.read()));

    out.close();
  }

  private static boolean isAndroid() {
    return System.getProperty("java.runtime.name", "").contains("Android");
  }

  private static boolean isWindows() {
    return OS_NAME.value().startsWith("Windows");
  }

   * A ticker that reads the current time using {@link System#nanoTime}.
   *
   * @since 10.0
   */
  public static Ticker systemTicker() {
    return SYSTEM_TICKER;
  }

  private static final Ticker SYSTEM_TICKER =
      new Ticker() {
        @Override
        @SuppressWarnings("GoodTime") // reading system time without TimeSource
        public long read() {
          return System.nanoTime();
        }
      };

     * than relying on the one from the system property.
     *
     * - Under Java 8, createTempDir() fails because it falls back to the bogus username from the
     * system property.
     */

    String save = System.getProperty("user.name");
    System.setProperty("user.name", "-this-is-definitely-not-the-username-we-are-running-as//?");
    try {

    long initialSize = cache.size();
    assertTrue(initialSize == 1 || initialSize == 2);

    // wait up to 5s
    byte[] filler = new byte[1024];
    for (int i = 0; i < 500; i++) {
      System.gc();

      CacheTesting.drainReferenceQueues(cache);
      if (cache.size() == 1) {
        break;
      }
      try {
        Thread.sleep(10);
      } catch (InterruptedException e) {

    else super.runTest();
  }

  protected void runTestProfiled() throws Throwable {
    long t0 = System.nanoTime();
    try {
      super.runTest();
    } finally {
      long elapsedMillis = (System.nanoTime() - t0) / (1000L * 1000L);
      if (elapsedMillis >= profileThreshold)
        System.out.printf("%n%s: %d%n", toString(), elapsedMillis);
    }
  }

  //     /**

 * are inherently approximate, routinely affected by periodic clock corrections. Because this class
 * (by default) uses {@link System#nanoTime}, it is unaffected by these changes.
 *
 * <p>Use this class instead of direct calls to {@link System#nanoTime} for two reasons:
 *
 * <ul>
 *   <li>The raw {@code long} values returned by {@code nanoTime} are meaningless and unsafe to use

    // Hack to load AbstractFuture et. al. in a new classloader so that it re-reads the cancellation
    // cause system property.  This allows us to run with both settings of the property in one jvm
    // without resorting to even crazier hacks to reset static final boolean fields.
    System.setProperty("guava.concurrent.generate_cancellation_cause", "true");
    final String concurrentPackage = SettableFuture.class.getPackage().getName();

    }
  }

  private static Character[] concat(Character[] left, Character[] right) {
    Character[] result = new Character[left.length + right.length];
    System.arraycopy(left, 0, result, 0, left.length);
    System.arraycopy(right, 0, result, left.length, right.length);
    return result;
  }

  public abstract static class TestCharListGenerator implements TestListGenerator<Character> {
    @Override