* large that doing the lookup is noticeably slower than redoing the work would be.
         *
         * Ideally we'd have a real eviction policy, but until we see a problem in practice, I hope
         * that this will suffice. I have not even benchmarked with different size limits.
         */
        if (validClasses.size() > 1000) {
          validClasses.clear();
        }

              @Override
              protected void finalize() {
                finalizerRan.countDown();
              }
            });

    await(finalizerRan);
    awaitClear(ref);

    // Hope to catch some stragglers queued up behind our finalizable object
    System.runFinalization();
  }

  private static RuntimeException formatRuntimeException(String format, Object... args) {

    t.start();
    return t;
  }

  /**
   * Waits for the specified time (in milliseconds) for the thread to terminate (using {@link
   * Thread#join(long)}), else interrupts the thread (in the hope that it may terminate later) and
   * fails.
   */
  void awaitTermination(Thread t, long timeoutMillis) {
    try {
      t.join(timeoutMillis);
    } catch (InterruptedException ie) {

 * <p><b>Note:</b> This class is similar to {@link CharEscaper} but with one very important
 * difference. A CharEscaper can only process Java <a
 * href="http://en.wikipedia.org/wiki/UTF-16">UTF16</a> characters in isolation and may not cope
 * when it encounters surrogate pairs. This class facilitates the correct escaping of all Unicode
 * characters.
 *
 * <p>As there are important reasons, including potential security issues, to handle Unicode

 * <p><b>Note:</b> This class is similar to {@link CharEscaper} but with one very important
 * difference. A CharEscaper can only process Java <a
 * href="http://en.wikipedia.org/wiki/UTF-16">UTF16</a> characters in isolation and may not cope
 * when it encounters surrogate pairs. This class facilitates the correct escaping of all Unicode
 * characters.
 *
 * <p>As there are important reasons, including potential security issues, to handle Unicode

     *
     * Expected outputs are generated by the code itself, but they've been
     * checked against the inputs under Bash in order to confirm that the two
     * forms are equivalent (though not necessarily minimal, though we hope this
     * to be the case). Thus, this test is more of a regression test.
     *
     * Rough instructions to regenerate the test outputs and verify correctness:
     * - Temporarily change this test:

              @Override
              protected void finalize() {
                finalizerRan.countDown();
              }
            });

    await(finalizerRan);
    awaitClear(ref);

    // Hope to catch some stragglers queued up behind our finalizable object
    System.runFinalization();
  }

  private static RuntimeException formatRuntimeException(String format, Object... args) {

         * large that doing the lookup is noticeably slower than redoing the work would be.
         *
         * Ideally we'd have a real eviction policy, but until we see a problem in practice, I hope
         * that this will suffice. I have not even benchmarked with different size limits.
         */
        if (validClasses.size() > 1000) {
          validClasses.clear();
        }

  @ListFeature.Require(absent = {SUPPORTS_SET, SUPPORTS_ADD_WITH_INDEX})
  public void testListIterator_unmodifiable() {
    runListIteratorTest(UNMODIFIABLE);
  }

  /*
   * For now, we don't cope with testing this when the list supports only some
   * modification operations.
   */
  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @ListFeature.Require({SUPPORTS_SET, SUPPORTS_ADD_WITH_INDEX})

    t.start();
    return t;
  }

  /**
   * Waits for the specified time (in milliseconds) for the thread to terminate (using {@link
   * Thread#join(long)}), else interrupts the thread (in the hope that it may terminate later) and
   * fails.
   */
  void awaitTermination(Thread t, long timeoutMillis) {
    try {
      t.join(timeoutMillis);
    } catch (InterruptedException ie) {