--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/java.base/share/classes/java/util/PrimitiveIterator.java Sun Aug 17 15:54:13 2014 +0100
@@ -0,0 +1,302 @@
+/*
+ * Copyright (c) 2013, 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
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package java.util;
+
+import java.util.function.Consumer;
+import java.util.function.DoubleConsumer;
+import java.util.function.IntConsumer;
+import java.util.function.LongConsumer;
+
+/**
+ * A base type for primitive specializations of {@code Iterator}. Specialized
+ * subtypes are provided for {@link OfInt int}, {@link OfLong long}, and
+ * {@link OfDouble double} values.
+ *
+ * <p>The specialized subtype default implementations of {@link Iterator#next}
+ * and {@link Iterator#forEachRemaining(java.util.function.Consumer)} box
+ * primitive values to instances of their corresponding wrapper class. Such
+ * boxing may offset any advantages gained when using the primitive
+ * specializations. To avoid boxing, the corresponding primitive-based methods
+ * should be used. For example, {@link PrimitiveIterator.OfInt#nextInt()} and
+ * {@link PrimitiveIterator.OfInt#forEachRemaining(java.util.function.IntConsumer)}
+ * should be used in preference to {@link PrimitiveIterator.OfInt#next()} and
+ * {@link PrimitiveIterator.OfInt#forEachRemaining(java.util.function.Consumer)}.
+ *
+ * <p>Iteration of primitive values using boxing-based methods
+ * {@link Iterator#next next()} and
+ * {@link Iterator#forEachRemaining(java.util.function.Consumer) forEachRemaining()},
+ * does not affect the order in which the values, transformed to boxed values,
+ * are encountered.
+ *
+ * @implNote
+ * If the boolean system property {@code org.openjdk.java.util.stream.tripwire}
+ * is set to {@code true} then diagnostic warnings are reported if boxing of
+ * primitive values occur when operating on primitive subtype specializations.
+ *
+ * @param <T> the type of elements returned by this PrimitiveIterator. The
+ * type must be a wrapper type for a primitive type, such as
+ * {@code Integer} for the primitive {@code int} type.
+ * @param <T_CONS> the type of primitive consumer. The type must be a
+ * primitive specialization of {@link java.util.function.Consumer} for
+ * {@code T}, such as {@link java.util.function.IntConsumer} for
+ * {@code Integer}.
+ *
+ * @since 1.8
+ */
+public interface PrimitiveIterator<T, T_CONS> extends Iterator<T> {
+
+ /**
+ * Performs the given action for each remaining element, in the order
+ * elements occur when iterating, until all elements have been processed
+ * or the action throws an exception. Errors or runtime exceptions
+ * thrown by the action are relayed to the caller.
+ *
+ * @param action The action to be performed for each element
+ * @throws NullPointerException if the specified action is null
+ */
+ @SuppressWarnings("overloads")
+ void forEachRemaining(T_CONS action);
+
+ /**
+ * An Iterator specialized for {@code int} values.
+ * @since 1.8
+ */
+ public static interface OfInt extends PrimitiveIterator<Integer, IntConsumer> {
+
+ /**
+ * Returns the next {@code int} element in the iteration.
+ *
+ * @return the next {@code int} element in the iteration
+ * @throws NoSuchElementException if the iteration has no more elements
+ */
+ int nextInt();
+
+ /**
+ * Performs the given action for each remaining element until all elements
+ * have been processed or the action throws an exception. Actions are
+ * performed in the order of iteration, if that order is specified.
+ * Exceptions thrown by the action are relayed to the caller.
+ *
+ * @implSpec
+ * <p>The default implementation behaves as if:
+ * <pre>{@code
+ * while (hasNext())
+ * action.accept(nextInt());
+ * }</pre>
+ *
+ * @param action The action to be performed for each element
+ * @throws NullPointerException if the specified action is null
+ */
+ default void forEachRemaining(IntConsumer action) {
+ Objects.requireNonNull(action);
+ while (hasNext())
+ action.accept(nextInt());
+ }
+
+ /**
+ * {@inheritDoc}
+ * @implSpec
+ * The default implementation boxes the result of calling
+ * {@link #nextInt()}, and returns that boxed result.
+ */
+ @Override
+ default Integer next() {
+ if (Tripwire.ENABLED)
+ Tripwire.trip(getClass(), "{0} calling PrimitiveIterator.OfInt.nextInt()");
+ return nextInt();
+ }
+
+ /**
+ * {@inheritDoc}
+ * @implSpec
+ * If the action is an instance of {@code IntConsumer} then it is cast
+ * to {@code IntConsumer} and passed to {@link #forEachRemaining};
+ * otherwise the action is adapted to an instance of
+ * {@code IntConsumer}, by boxing the argument of {@code IntConsumer},
+ * and then passed to {@link #forEachRemaining}.
+ */
+ @Override
+ default void forEachRemaining(Consumer<? super Integer> action) {
+ if (action instanceof IntConsumer) {
+ forEachRemaining((IntConsumer) action);
+ }
+ else {
+ // The method reference action::accept is never null
+ Objects.requireNonNull(action);
+ if (Tripwire.ENABLED)
+ Tripwire.trip(getClass(), "{0} calling PrimitiveIterator.OfInt.forEachRemainingInt(action::accept)");
+ forEachRemaining((IntConsumer) action::accept);
+ }
+ }
+
+ }
+
+ /**
+ * An Iterator specialized for {@code long} values.
+ * @since 1.8
+ */
+ public static interface OfLong extends PrimitiveIterator<Long, LongConsumer> {
+
+ /**
+ * Returns the next {@code long} element in the iteration.
+ *
+ * @return the next {@code long} element in the iteration
+ * @throws NoSuchElementException if the iteration has no more elements
+ */
+ long nextLong();
+
+ /**
+ * Performs the given action for each remaining element until all elements
+ * have been processed or the action throws an exception. Actions are
+ * performed in the order of iteration, if that order is specified.
+ * Exceptions thrown by the action are relayed to the caller.
+ *
+ * @implSpec
+ * <p>The default implementation behaves as if:
+ * <pre>{@code
+ * while (hasNext())
+ * action.accept(nextLong());
+ * }</pre>
+ *
+ * @param action The action to be performed for each element
+ * @throws NullPointerException if the specified action is null
+ */
+ default void forEachRemaining(LongConsumer action) {
+ Objects.requireNonNull(action);
+ while (hasNext())
+ action.accept(nextLong());
+ }
+
+ /**
+ * {@inheritDoc}
+ * @implSpec
+ * The default implementation boxes the result of calling
+ * {@link #nextLong()}, and returns that boxed result.
+ */
+ @Override
+ default Long next() {
+ if (Tripwire.ENABLED)
+ Tripwire.trip(getClass(), "{0} calling PrimitiveIterator.OfLong.nextLong()");
+ return nextLong();
+ }
+
+ /**
+ * {@inheritDoc}
+ * @implSpec
+ * If the action is an instance of {@code LongConsumer} then it is cast
+ * to {@code LongConsumer} and passed to {@link #forEachRemaining};
+ * otherwise the action is adapted to an instance of
+ * {@code LongConsumer}, by boxing the argument of {@code LongConsumer},
+ * and then passed to {@link #forEachRemaining}.
+ */
+ @Override
+ default void forEachRemaining(Consumer<? super Long> action) {
+ if (action instanceof LongConsumer) {
+ forEachRemaining((LongConsumer) action);
+ }
+ else {
+ // The method reference action::accept is never null
+ Objects.requireNonNull(action);
+ if (Tripwire.ENABLED)
+ Tripwire.trip(getClass(), "{0} calling PrimitiveIterator.OfLong.forEachRemainingLong(action::accept)");
+ forEachRemaining((LongConsumer) action::accept);
+ }
+ }
+ }
+
+ /**
+ * An Iterator specialized for {@code double} values.
+ * @since 1.8
+ */
+ public static interface OfDouble extends PrimitiveIterator<Double, DoubleConsumer> {
+
+ /**
+ * Returns the next {@code double} element in the iteration.
+ *
+ * @return the next {@code double} element in the iteration
+ * @throws NoSuchElementException if the iteration has no more elements
+ */
+ double nextDouble();
+
+ /**
+ * Performs the given action for each remaining element until all elements
+ * have been processed or the action throws an exception. Actions are
+ * performed in the order of iteration, if that order is specified.
+ * Exceptions thrown by the action are relayed to the caller.
+ *
+ * @implSpec
+ * <p>The default implementation behaves as if:
+ * <pre>{@code
+ * while (hasNext())
+ * action.accept(nextDouble());
+ * }</pre>
+ *
+ * @param action The action to be performed for each element
+ * @throws NullPointerException if the specified action is null
+ */
+ default void forEachRemaining(DoubleConsumer action) {
+ Objects.requireNonNull(action);
+ while (hasNext())
+ action.accept(nextDouble());
+ }
+
+ /**
+ * {@inheritDoc}
+ * @implSpec
+ * The default implementation boxes the result of calling
+ * {@link #nextDouble()}, and returns that boxed result.
+ */
+ @Override
+ default Double next() {
+ if (Tripwire.ENABLED)
+ Tripwire.trip(getClass(), "{0} calling PrimitiveIterator.OfDouble.nextLong()");
+ return nextDouble();
+ }
+
+ /**
+ * {@inheritDoc}
+ * @implSpec
+ * If the action is an instance of {@code DoubleConsumer} then it is
+ * cast to {@code DoubleConsumer} and passed to
+ * {@link #forEachRemaining}; otherwise the action is adapted to
+ * an instance of {@code DoubleConsumer}, by boxing the argument of
+ * {@code DoubleConsumer}, and then passed to
+ * {@link #forEachRemaining}.
+ */
+ @Override
+ default void forEachRemaining(Consumer<? super Double> action) {
+ if (action instanceof DoubleConsumer) {
+ forEachRemaining((DoubleConsumer) action);
+ }
+ else {
+ // The method reference action::accept is never null
+ Objects.requireNonNull(action);
+ if (Tripwire.ENABLED)
+ Tripwire.trip(getClass(), "{0} calling PrimitiveIterator.OfDouble.forEachRemainingDouble(action::accept)");
+ forEachRemaining((DoubleConsumer) action::accept);
+ }
+ }
+ }
+}