src/java.base/share/classes/java/util/stream/Stream.java

*** 1,7 ****
  /*
!  * Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
--- 1,7 ----
  /*
!  * Copyright (c) 2012, 2016, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
*** 1183,1209 ****
       *          a new element
       * @return a new sequential {@code Stream}
       */
      public static<T> Stream<T> iterate(final T seed, final UnaryOperator<T> f) {
          Objects.requireNonNull(f);
!         final Iterator<T> iterator = new Iterator<T>() {
!             @SuppressWarnings("unchecked")
!             T t = (T) Streams.NONE;
  
              @Override
!             public boolean hasNext() {
                  return true;
              }
  
              @Override
!             public T next() {
!                 return t = (t == Streams.NONE) ? seed : f.apply(t);
              }
          };
!         return StreamSupport.stream(Spliterators.spliteratorUnknownSize(
!                 iterator,
!                 Spliterator.ORDERED | Spliterator.IMMUTABLE), false);
      }
  
      /**
       * Returns an infinite sequential unordered stream where each element is
       * generated by the provided {@code Supplier}.  This is suitable for
--- 1183,1289 ----
       *          a new element
       * @return a new sequential {@code Stream}
       */
      public static<T> Stream<T> iterate(final T seed, final UnaryOperator<T> f) {
          Objects.requireNonNull(f);
!         Spliterator<T> spliterator = new Spliterators.AbstractSpliterator<>(Long.MAX_VALUE, 
!                Spliterator.ORDERED | Spliterator.IMMUTABLE) {
!             T prev;
!             boolean started;
  
              @Override
!             public boolean tryAdvance(Consumer<? super T> action) {
!                 Objects.requireNonNull(action);
!                 T t;
!                 if (started)
!                     t = f.apply(prev);
!                 else {
!                     t = seed;
!                     started = true;
!                 }
!                 action.accept(prev = t);
!                 return true;
!             }
!         };
!         return StreamSupport.stream(spliterator, false);
!     }
! 
!     /**
!      * Returns a sequential ordered {@code Stream} produced by iterative
!      * application of a function to an initial element, conditioned on 
!      * satisfying the supplied predicate.  The stream terminates as soon as
!      * the predicate function returns false.
!      *
!      * <p>
!      * {@code Stream.iterate} should produce the same sequence of elements as
!      * produced by the corresponding for-loop:
!      * <pre>{@code
!      *     for (T index=seed; predicate.test(index); index = f.apply(index)) { 
!      *         ... 
!      *     }
!      * }</pre>
!      *
!      * <p>
!      * The resulting sequence may be empty if the predicate does not hold on 
!      * the seed value.  Otherwise the first element will be the supplied seed
!      * value, the next element (if present) will be the result of applying the
!      * function f to the seed value, and so on iteratively until the predicate
!      * indicates that the stream should terminate.
!      *
!      * @param <T> the type of stream elements
!      * @param seed the initial element
!      * @param predicate a predicate to apply to elements to determine when the 
!      *          stream must terminate.
!      * @param f a function to be applied to the previous element to produce
!      *          a new element
!      * @return a new sequential {@code Stream}
!      * @since 9
!      */
!     public static<T> Stream<T> iterate(T seed, Predicate<? super T> predicate, UnaryOperator<T> f) {
!         Objects.requireNonNull(f);
!         Objects.requireNonNull(predicate);
!         Spliterator<T> spliterator = new Spliterators.AbstractSpliterator<>(Long.MAX_VALUE, 
!                Spliterator.ORDERED | Spliterator.IMMUTABLE) {
!             T prev;
!             boolean started, finished;
! 
!             @Override
!             public boolean tryAdvance(Consumer<? super T> action) {
!                 Objects.requireNonNull(action);
!                 if (finished)
!                     return false;
!                 T t;
!                 if (started)
!                     t = f.apply(prev);
!                 else {
!                     t = seed;
!                     started = true;
!                 }
!                 if (!predicate.test(t)) {
!                     prev = null;
!                     finished = true;
!                     return false;
!                 }
!                 action.accept(prev = t);
                  return true;
              }
  
              @Override
!             public void forEachRemaining(Consumer<? super T> action) {
!                 Objects.requireNonNull(action);
!                 if (finished)
!                     return;
!                 finished = true;
!                 T t = started ? f.apply(prev) : seed;
!                 prev = null;
!                 while (predicate.test(t)) {
!                     action.accept(t);
!                     t = f.apply(t);
!                 }
              }
          };
!         return StreamSupport.stream(spliterator, false);
      }
  
      /**
       * Returns an infinite sequential unordered stream where each element is
       * generated by the provided {@code Supplier}.  This is suitable for