checkNotNull(appendable, "appendable");
        checkNotNull(parts, "parts");
        while (parts.hasNext()) {
          Object part = parts.next();
          if (part != null) {
            appendable.append(Joiner.this.toString(part));
            break;
          }
        }
        while (parts.hasNext()) {
          Object part = parts.next();

        }
      };

  private static void checkResult(Joiner joiner, Iterable<Integer> parts, String expected) {
    assertEquals(expected, joiner.join(parts));
    assertEquals(expected, joiner.join(parts.iterator()));

    StringBuilder sb1FromIterable = new StringBuilder().append('x');
    joiner.appendTo(sb1FromIterable, parts);
    assertEquals("x" + expected, sb1FromIterable.toString());

    try {
      return satisfied = guard.isSatisfied();
    } finally {
      if (!satisfied) {
        lock.unlock();
      }
    }
  }

  /**
   * Waits for the guard to be satisfied. Waits indefinitely, but may be interrupted. May be called
   * only by a thread currently occupying this monitor.
   *
   * @throws InterruptedException if interrupted while waiting
   */

      threadUnexpectedException(t);
    }
  }

  //     /**
  //      * Spin-waits up to LONG_DELAY_MS until flag becomes true.
  //      */
  //     public void await(AtomicBoolean flag) {
  //         await(flag, LONG_DELAY_MS);
  //     }

  //     /**
  //      * Spin-waits up to the specified timeout until flag becomes true.
  //      */

      @ParametricNullness E fromElement,
      BoundType fromBoundType,
      @ParametricNullness E toElement,
      BoundType toBoundType) {
    // These are checked elsewhere, but NullPointerTester wants them checked eagerly.
    checkNotNull(fromBoundType);
    checkNotNull(toBoundType);
    return tailMultiset(fromElement, fromBoundType).headMultiset(toElement, toBoundType);
  }

    own the intellectual property, then you'll need to sign an [individual
    CLA][]. Please include your GitHub username.
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    then you'll need to sign a [corporate CLA][].

You generally only need to submit a CLA once, so if you've already submitted

          element = entry.getElement();
          remaining = entry.getCount();
        }
        remaining--;
        /*
         * requireNonNull is safe because `remaining` starts at 0, forcing us to initialize
         * `element` above. After that, we never clear it.
         */
        return requireNonNull(element);
      }
    };
  }

     * to confirm that it is running. If the main thread's stop() call happens
     * before it has the chance, the test will fail. To avoid this, the main
     * thread calls this method, which waits until the service has performed
     * its own "running" check.
     */
    void awaitRunChecks() throws InterruptedException {
      assertTrue(
          "Service thread hasn't finished its checks. "

    return stringWriter.toString();
  }

  /**
   * Returns the stack trace of {@code throwable}, possibly providing slower iteration over the full
   * trace but faster iteration over parts of the trace. Here, "slower" and "faster" are defined in
   * comparison to the normal way to access the stack trace, {@link Throwable#getStackTrace()

    return stringWriter.toString();
  }

  /**
   * Returns the stack trace of {@code throwable}, possibly providing slower iteration over the full
   * trace but faster iteration over parts of the trace. Here, "slower" and "faster" are defined in
   * comparison to the normal way to access the stack trace, {@link Throwable#getStackTrace()