From f17b0a41667d8b1a5785245603dbc66c79d63639 Mon Sep 17 00:00:00 2001 From: emptypoint Date: Sat, 6 Aug 2022 23:36:25 +0800 Subject: [PATCH] =?UTF-8?q?1.=E5=88=A0=E9=99=A4=E5=A4=9A=E4=BD=99=E6=96=87?= =?UTF-8?q?=E4=BB=B6;=202.=E8=B0=83=E6=95=B4=E6=B3=A8=E9=87=8A=E4=BD=8D?= =?UTF-8?q?=E7=BD=AE;?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- .../cn/hutool/core/stream/FastStream.java | 7 +- .../stream/support/DropWhileSpliterator.java | 72 -------------- .../stream/support/IterateSpliterator.java | 76 -------------- .../core/stream/support/StreamHelper.java | 99 ------------------- .../stream/support/TakeWhileSpliterator.java | 68 ------------- 5 files changed, 4 insertions(+), 318 deletions(-) delete mode 100644 hutool-core/src/main/java/cn/hutool/core/stream/support/DropWhileSpliterator.java delete mode 100644 hutool-core/src/main/java/cn/hutool/core/stream/support/IterateSpliterator.java delete mode 100644 hutool-core/src/main/java/cn/hutool/core/stream/support/StreamHelper.java delete mode 100644 hutool-core/src/main/java/cn/hutool/core/stream/support/TakeWhileSpliterator.java diff --git a/hutool-core/src/main/java/cn/hutool/core/stream/FastStream.java b/hutool-core/src/main/java/cn/hutool/core/stream/FastStream.java index 13fdd7182..ca83b2488 100644 --- a/hutool-core/src/main/java/cn/hutool/core/stream/FastStream.java +++ b/hutool-core/src/main/java/cn/hutool/core/stream/FastStream.java @@ -6,7 +6,6 @@ import cn.hutool.core.lang.Opt; import cn.hutool.core.lang.mutable.MutableInt; import cn.hutool.core.lang.mutable.MutableObj; import cn.hutool.core.map.MapUtil; -import cn.hutool.core.stream.support.StreamHelper; import cn.hutool.core.text.StrUtil; import cn.hutool.core.util.ArrayUtil; @@ -669,13 +668,15 @@ public class FastStream implements Stream, Iterable { /** * 返回一个包含此流元素的指定的数组 + *

+ * 例如以下代码编译正常，但运行时会抛出 {@link ArrayStoreException} + * 

{@code String[] strings = Stream.builder().add(1).build().toArray(String[]::new); }
+ *

* * @param generator 这里的IntFunction的参数是元素的个数，返回值为数组类型 * @param 给定的数组类型 * @return 包含此流元素的指定的数组 * @throws ArrayStoreException 如果元素转换失败，例如不是该元素类型及其父类，则抛出该异常 - * 例如以下代码编译正常，但运行时会抛出 {@link ArrayStoreException} - * 
{@code String[] strings = Stream.builder().add(1).build().toArray(String[]::new); }
*/ @Override public A[] toArray(IntFunction generator) { diff --git a/hutool-core/src/main/java/cn/hutool/core/stream/support/DropWhileSpliterator.java b/hutool-core/src/main/java/cn/hutool/core/stream/support/DropWhileSpliterator.java deleted file mode 100644 index 0ab4433a9..000000000 --- a/hutool-core/src/main/java/cn/hutool/core/stream/support/DropWhileSpliterator.java +++ /dev/null @@ -1,72 +0,0 @@ -package cn.hutool.core.stream.support; - -import java.util.Comparator; -import java.util.Spliterator; -import java.util.function.Consumer; -import java.util.function.Predicate; - -/** - * dropWhile 的 Spliterator - *

借鉴自StreamEx

- * - * @author emptypoint - * @since 6.0.0 - */ -class DropWhileSpliterator implements Spliterator { - - static DropWhileSpliterator create(Spliterator source, Predicate predicate) { - return new DropWhileSpliterator<>(source, predicate); - } - - private final Spliterator source; - private final Predicate predicate; - private boolean isFound = false; - - private DropWhileSpliterator(Spliterator source, Predicate predicate) { - this.source = source; - this.predicate = predicate; - } - - @Override - public boolean tryAdvance(Consumer action) { - boolean hasNext = true; - // 如果 还没找到 并且 流中还有元素 继续找 - while (!isFound && hasNext) { - hasNext = source.tryAdvance(e -> { - if (!predicate.test(e)) { - // 第一次不匹配 - isFound = true; - action.accept(e); - } - }); - } - - // 对找到的元素进行后续处理 - if (isFound) { - source.forEachRemaining(action); - } - - // 该环节已经处理完成 - return false; - } - - @Override - public Spliterator trySplit() { - return null; - } - - @Override - public long estimateSize() { - return Long.MAX_VALUE; - } - - @Override - public int characteristics() { - return source.characteristics() & ~Spliterator.SIZED; - } - - @Override - public Comparator getComparator() { - return source.getComparator(); - } -} diff --git a/hutool-core/src/main/java/cn/hutool/core/stream/support/IterateSpliterator.java b/hutool-core/src/main/java/cn/hutool/core/stream/support/IterateSpliterator.java deleted file mode 100644 index 71df09b7b..000000000 --- a/hutool-core/src/main/java/cn/hutool/core/stream/support/IterateSpliterator.java +++ /dev/null @@ -1,76 +0,0 @@ -package cn.hutool.core.stream.support; - -import java.util.Objects; -import java.util.Spliterator; -import java.util.Spliterators; -import java.util.function.Consumer; -import java.util.function.Predicate; -import java.util.function.UnaryOperator; - -/** - * 无限有序流 的Spliterator - * - * @author VampireAchao - * @since 6.0.0 - */ -class IterateSpliterator extends Spliterators.AbstractSpliterator { - public static IterateSpliterator create(T seed, Predicate hasNext, UnaryOperator next) { - return new IterateSpliterator<>(seed, hasNext, next); - } - - /** - * Creates a spliterator reporting the given estimated size and - * additionalCharacteristics. - */ - IterateSpliterator(T seed, Predicate hasNext, UnaryOperator next) { - super(Long.MAX_VALUE, Spliterator.ORDERED | Spliterator.IMMUTABLE); - this.seed = seed; - this.hasNext = hasNext; - this.next = next; - } - - private final T seed; - private final Predicate hasNext; - private final UnaryOperator next; - private T prev; - private boolean started; - private boolean finished; - - @Override - public boolean tryAdvance(Consumer action) { - Objects.requireNonNull(action); - if (finished) { - return false; - } - T t; - if (started) { - t = next.apply(prev); - } else { - t = seed; - started = true; - } - if (!hasNext.test(t)) { - prev = null; - finished = true; - return false; - } - prev = t; - action.accept(prev); - return true; - } - - @Override - public void forEachRemaining(Consumer action) { - Objects.requireNonNull(action); - if (finished) { - return; - } - finished = true; - T t = started ? next.apply(prev) : seed; - prev = null; - while (hasNext.test(t)) { - action.accept(t); - t = next.apply(t); - } - } -} diff --git a/hutool-core/src/main/java/cn/hutool/core/stream/support/StreamHelper.java b/hutool-core/src/main/java/cn/hutool/core/stream/support/StreamHelper.java deleted file mode 100644 index 478cbb091..000000000 --- a/hutool-core/src/main/java/cn/hutool/core/stream/support/StreamHelper.java +++ /dev/null @@ -1,99 +0,0 @@ -package cn.hutool.core.stream.support; - -import java.util.Spliterator; -import java.util.function.Predicate; -import java.util.function.UnaryOperator; -import java.util.stream.Stream; -import java.util.stream.StreamSupport; - -import static java.util.Objects.requireNonNull; - -/** - * FastStream 辅助工具类 - * - * @author emptypoint - * @since 6.0.0 - */ -public final class StreamHelper { - private StreamHelper() { - } - - /** - * 返回无限有序流 - * 该流由 初始值 然后判断条件 以及执行 迭代函数 进行迭代获取到元素 - * - * @param 元素类型 - * @param seed 初始值 - * @param hasNext 条件值 - * @param next 用上一个元素作为参数执行并返回一个新的元素 - * @return 无限有序流 - */ - public static Stream iterate(T seed, Predicate hasNext, UnaryOperator next) { - requireNonNull(next); - requireNonNull(hasNext); - return StreamSupport.stream(IterateSpliterator.create(seed, hasNext, next), false); - } - - /** - * 保留 与指定断言 匹配时的元素, 在第一次不匹配时终止, 抛弃当前(第一个不匹配元素)及后续所有元素 - *

与 jdk9 中的 takeWhile 方法不太一样, 这里的实现是个 顺序的、有状态的中间操作

- *

本环节中是顺序执行的, 但是后续操作可以支持并行流

- *

但是不建议在并行流中使用, 除非你确定 takeWhile 之后的操作能在并行流中受益很多

- * - * @param source 源流 - * @param 元素类型 - * @param predicate 断言 - * @return 与指定断言匹配的元素组成的流 - */ - public static Stream takeWhile(Stream source, Predicate predicate) { - requireNonNull(source); - requireNonNull(predicate); - return createStatefulNewStream(source, TakeWhileSpliterator.create(source.spliterator(), predicate)); - } - - /** - * 删除 与指定断言 匹配的元素, 在第一次不匹配时终止, 返回当前(第一个不匹配元素)及剩余元素组成的新流 - *

与 jdk9 中的 dropWhile 方法不太一样, 这里的实现是个 顺序的、有状态的中间操作

- *

本环节中是顺序执行的, 但是后续操作可以支持并行流

- *

但是不建议在并行流中使用, 除非你确定 dropWhile 之后的操作能在并行流中受益很多

- * - * @param source 源流 - * @param 元素类型 - * @param predicate 断言 - * @return 剩余元素组成的流 - */ - public static Stream dropWhile(Stream source, Predicate predicate) { - requireNonNull(source); - requireNonNull(predicate); - return createStatefulNewStream(source, DropWhileSpliterator.create(source.spliterator(), predicate)); - } - - // region 私有方法 - /* ================================================== 私有方法 =================================================== */ - - /** - * 根据 源流 和 新的Spliterator 生成新的流 - *

这是一个 顺序的、有状态的流

- *

在新流的第一个节点是顺序执行的, 但是后续操作可以支持并行流

- * - * @param source 源流 - * @param newSpliterator 新流的Spliterator - * @param 旧流的元素类型 - * @param 新流的元素类型 - * @return 新流 - */ - private static Stream createStatefulNewStream(Stream source, Spliterator newSpliterator) { - // 创建新流 - Stream newStream = StreamSupport.stream(newSpliterator, source.isParallel()); - // 如果旧流是并行流, 新流主动调用一个有状态的操作, 虽然没有意义, 但是可以让后续的无状态节点正常并发 - if (source.isParallel()) { - newStream = newStream.limit(Long.MAX_VALUE); - } - // 由于新流不与旧流的节点关联, 所以需要主动设置旧流的close方法, 哪怕几乎不可能有人在旧流上设置onClose操作 - return newStream.onClose(source::close); - } - - /* ============================================================================================================== */ - // endregion - -} diff --git a/hutool-core/src/main/java/cn/hutool/core/stream/support/TakeWhileSpliterator.java b/hutool-core/src/main/java/cn/hutool/core/stream/support/TakeWhileSpliterator.java deleted file mode 100644 index dc0ca8da6..000000000 --- a/hutool-core/src/main/java/cn/hutool/core/stream/support/TakeWhileSpliterator.java +++ /dev/null @@ -1,68 +0,0 @@ -package cn.hutool.core.stream.support; - -import java.util.Comparator; -import java.util.Spliterator; -import java.util.function.Consumer; -import java.util.function.Predicate; - -/** - * takeWhile 的 Spliterator - *

借鉴自StreamEx

- * - * @author emptypoint - * @since 6.0.0 - */ -class TakeWhileSpliterator implements Spliterator { - - static TakeWhileSpliterator create(Spliterator source, Predicate predicate) { - return new TakeWhileSpliterator<>(source, predicate); - } - - private final Spliterator source; - private final Predicate predicate; - private boolean isContinue = true; - - TakeWhileSpliterator(Spliterator source, Predicate predicate) { - this.source = source; - this.predicate = predicate; - } - - @Override - public boolean tryAdvance(Consumer action) { - boolean hasNext = true; - // 如果 还可以继续 并且 流中还有元素 则继续遍历 - while (isContinue && hasNext) { - hasNext = source.tryAdvance(e -> { - if (predicate.test(e)) { - action.accept(e); - } else { - // 终止遍历剩下的元素 - isContinue = false; - } - }); - } - // 该环节已经处理完成 - return false; - } - - @Override - public Spliterator trySplit() { - return null; - } - - @Override - public long estimateSize() { - return isContinue ? source.estimateSize() : 0; - } - - @Override - public int characteristics() { - return source.characteristics() & ~(Spliterator.SIZED | Spliterator.SUBSIZED); - } - - @Override - public Comparator getComparator() { - return source.getComparator(); - } -} -