}

  public void testClosesOnErrors_copyingFromCharSourceThatThrows() {
    for (TestOption option : EnumSet.of(OPEN_THROWS, READ_THROWS, CLOSE_THROWS)) {
      TestCharSource failSource = new TestCharSource(STRING, option);
      TestCharSink okSink = new TestCharSink();
      assertThrows(IOException.class, () -> failSource.copyTo(okSink));

 *
 * @author Colin Decker
 */
public class TestCharSink extends CharSink implements TestStreamSupplier {

  private final TestByteSink byteSink;

  public TestCharSink(TestOption... options) {
    this.byteSink = new TestByteSink(options);
  }

  public String getString() {
    return new String(byteSink.getBytes(), UTF_8);
  }

  @Override
  public boolean wasStreamOpened() {
    return byteSink.wasStreamOpened();

   * Splitter.on(',').omitEmptyStrings().split(",a,,,b,c,,")} returns an iterable containing only
   * {@code ["a", "b", "c"]}.
   *
   * <p>If either {@code trimResults} option is also specified when creating a splitter, that
   * splitter always trims results first before checking for emptiness. So, for example, {@code

  private final ImmutableSet<TestOption> options;
  private boolean closed;

  public TestOutputStream(OutputStream out, TestOption... options) throws IOException {
    this(out, Arrays.asList(options));
  }

  public TestOutputStream(OutputStream out, Iterable<TestOption> options) throws IOException {
    super(checkNotNull(out));
    this.options = ImmutableSet.copyOf(options);
    throwIf(OPEN_THROWS);
  }

  private final ImmutableSet<TestOption> options;
  private boolean closed;

  public TestInputStream(InputStream in, TestOption... options) throws IOException {
    this(in, Arrays.asList(options));
  }

  public TestInputStream(InputStream in, Iterable<TestOption> options) throws IOException {
    super(checkNotNull(in));
    this.options = ImmutableSet.copyOf(options);
    throwIf(OPEN_THROWS);
  }

  private final ImmutableSet<TestOption> options;
  private boolean closed;

  public TestInputStream(InputStream in, TestOption... options) throws IOException {
    this(in, Arrays.asList(options));
  }

  public TestInputStream(InputStream in, Iterable<TestOption> options) throws IOException {
    super(checkNotNull(in));
    this.options = ImmutableSet.copyOf(options);
    throwIf(OPEN_THROWS);
  }

    assertEquals("foo!bar!baz!", sink.getString());
  }

  public void testClosesOnErrors_copyingFromCharSourceThatThrows() {
    for (TestOption option : EnumSet.of(OPEN_THROWS, READ_THROWS, CLOSE_THROWS)) {
      TestCharSource failSource = new TestCharSource(STRING, option);
      TestCharSink okSink = new TestCharSink();
      assertThrows(IOException.class, () -> failSource.copyTo(okSink));

  }

  public void testClosesOnErrors_copyingToCharSinkThatThrows() {
    for (TestOption option : EnumSet.of(OPEN_THROWS, WRITE_THROWS, CLOSE_THROWS)) {
      TestCharSource okSource = new TestCharSource(STRING);
      assertThrows(IOException.class, () -> okSource.copyTo(new TestCharSink(option)));
      // ensure reader was closed IF it was opened (depends on implementation whether or not it's

 */
@DoNotMock("Use Optional.of(value) or Optional.absent()")
@GwtCompatible(serializable = true)
@ElementTypesAreNonnullByDefault
public abstract class Optional<T> implements Serializable {
  /**
   * Returns an {@code Optional} instance with no contained reference.
   *
   * <p><b>Comparison to {@code java.util.Optional}:</b> this method is equivalent to Java 8's
   * {@code Optional.empty}.
   */
  public static <T> Optional<T> absent() {

   * Splitter.on(',').omitEmptyStrings().split(",a,,,b,c,,")} returns an iterable containing only
   * {@code ["a", "b", "c"]}.
   *
   * <p>If either {@code trimResults} option is also specified when creating a splitter, that
   * splitter always trims results first before checking for emptiness. So, for example, {@code