final boolean cas(long cmp, long val) {
      return UNSAFE.compareAndSwapLong(this, VALUE_OFFSET, cmp, val);
    }

    // Unsafe mechanics
    private static final Unsafe UNSAFE;
    private static final long VALUE_OFFSET;

    static {
      try {
        UNSAFE = getUnsafe();
        Class<?> ak = Cell.class;
        VALUE_OFFSET = UNSAFE.objectFieldOffset(ak.getDeclaredField("value"));

    static {
      Unsafe unsafe = null;
      try {
        unsafe = Unsafe.getUnsafe();
      } catch (SecurityException tryReflectionInstead) {
        try {
          unsafe =
              doPrivileged(
                  (PrivilegedExceptionAction<Unsafe>)
                      () -> {
                        Class<Unsafe> k = Unsafe.class;

    private static final Unsafe theUnsafe;

    // The offset to the first element in a byte array.
    private static final int BYTE_ARRAY_BASE_OFFSET;

    /**
     * Returns an Unsafe. Suitable for use in a 3rd party package. Replace with a simple call to
     * Unsafe.getUnsafe when integrating into a JDK.
     *
     * @return an Unsafe instance if successful
     */

    static {
      Unsafe unsafe = null;
      try {
        unsafe = Unsafe.getUnsafe();
      } catch (SecurityException tryReflectionInstead) {
        try {
          unsafe =
              doPrivileged(
                  (PrivilegedExceptionAction<Unsafe>)
                      () -> {
                        Class<Unsafe> k = Unsafe.class;

   * which will prevent us from selecting the {@code UnsafeAtomicHelper} strategy.
   */
  private static final ClassLoader NO_UNSAFE =
      getClassLoader(ImmutableSet.of("java.lang.invoke.VarHandle", "sun.misc.Unsafe"));

  /**
   * This classloader disallows {@link java.lang.invoke.VarHandle}, {@link sun.misc.Unsafe} and

  public void testBuilderRetainsState() {
    // Setting a safe range and unsafe replacement works as expected.
    Escapers.Builder builder = Escapers.builder();
    builder.setSafeRange('a', 'z');
    builder.setUnsafeReplacement("X");
    assertThat(builder.build().escape("The Quick Brown Fox!")).isEqualTo("XheXXuickXXrownXXoxX");
    // Explicit replacements take priority over unsafe characters.
    builder.addEscape(' ', "_");

   *
   * <p>If a code point has no mapped replacement then it is checked against the safe range. If it
   * lies outside that, then {@link #escapeUnsafe} is called, otherwise no escaping is performed.
   *
   * @param replacementMap a map of characters to their escaped representations
   * @param safeMin the lowest character value in the safe range
   * @param safeMax the highest character value in the safe range

   *
   * <p><b>{@code Stream} equivalent:</b> {@code stream.filter(predicate).findFirst()}.
   */
  public final Optional<@NonNull E> firstMatch(Predicate<? super E> predicate) {
    // Unsafe, but we can't do much about it now.
    return Iterables.<@NonNull E>tryFind((Iterable<@NonNull E>) getDelegate(), predicate);
  }

  /**

   *
   * <p><b>{@code Stream} equivalent:</b> {@code stream.filter(predicate).findFirst()}.
   */
  public final Optional<@NonNull E> firstMatch(Predicate<? super E> predicate) {
    // Unsafe, but we can't do much about it now.
    return Iterables.<@NonNull E>tryFind((Iterable<@NonNull E>) getDelegate(), predicate);
  }

  /**

func parseDirEnt(buf []byte) (consumed int, name []byte, typ os.FileMode, err error) {
	// golang.org/issue/15653
	dirent := (*syscall.Dirent)(unsafe.Pointer(&buf[0]))
	if v := unsafe.Offsetof(dirent.Reclen) + unsafe.Sizeof(dirent.Reclen); uintptr(len(buf)) < v {
		return consumed, nil, typ, fmt.Errorf("buf size of %d smaller than dirent header size %d", len(buf), v)
	}
	if len(buf) < int(dirent.Reclen) {