Track libcore change 2c423c81bfa731df2577a. am: 34bfcf1f

    method public abstract void update(java.util.Observable, java.lang.Object);

  }

  public final class Optional {

    method public static java.util.Optional<T> empty();

    method public java.util.Optional<T> filter(java.util.function.Predicate<? super T>);

    method public java.util.Optional<U> flatMap(java.util.function.Function<? super T, java.util.Optional<U>>);

    method public T get();

    method public void ifPresent(java.util.function.Consumer<? super T>);

    method public boolean isPresent();

    method public java.util.Optional<U> map(java.util.function.Function<? super T, ? extends U>);

    method public static java.util.Optional<T> of(T);

    method public static java.util.Optional<T> ofNullable(T);

    method public T orElse(T);

    method public T orElseGet(java.util.function.Supplier<? extends T>);

    method public T orElseThrow(java.util.function.Supplier<? extends X>) throws java.lang.Throwable;

  }

  public final class OptionalDouble {

    method public static java.util.OptionalDouble empty();

    method public double getAsDouble();

    method public void ifPresent(java.util.function.DoubleConsumer);

    method public boolean isPresent();

    method public static java.util.OptionalDouble of(double);

    method public double orElse(double);

    method public double orElseGet(java.util.function.DoubleSupplier);

    method public double orElseThrow(java.util.function.Supplier<X>) throws java.lang.Throwable;

  }

  public final class OptionalInt {

    method public static java.util.OptionalInt empty();

    method public int getAsInt();

    method public void ifPresent(java.util.function.IntConsumer);

    method public boolean isPresent();

    method public static java.util.OptionalInt of(int);

    method public int orElse(int);

    method public int orElseGet(java.util.function.IntSupplier);

    method public int orElseThrow(java.util.function.Supplier<X>) throws java.lang.Throwable;

  }

  public final class OptionalLong {

    method public static java.util.OptionalLong empty();

    method public long getAsLong();

    method public void ifPresent(java.util.function.LongConsumer);

    method public boolean isPresent();

    method public static java.util.OptionalLong of(long);

    method public long orElse(long);

    method public long orElseGet(java.util.function.LongSupplier);

    method public long orElseThrow(java.util.function.Supplier<X>) throws java.lang.Throwable;

  }

  public class PriorityQueue extends java.util.AbstractQueue implements java.io.Serializable {

    ctor public PriorityQueue();

    ctor public PriorityQueue(int);