Stream flow

1.stream.forEach() 与 collection.forEach()

Although there are iterative methods, but the results are completely different.

Such as:

List<String> strl=Arrays.asList("aaa","bb","c","wwww","hh");

Stream.of(strl).forEach(System.out::println);------------------------------------------------------>①
System.out.println("^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^");
strl.stream().forEach(System.out::println);-------------------------------------------------------->②
System.out.println("^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^");
strl.forEach(System.out::println);----------------------------------------------------------------->③

Output:

[aaa, bb, c, hh, wwww]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
aaa
bb
c
hh
wwww
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
aaa
bb
c
hh
wwww

Although the idea of suggesting ② line can be abbreviated form of the third row, but

①② in forEach () points to Stream interface and ③ in forEach () points to the Iterable interface.

View seen:

① of () method returns with one element of the Stream Stream Interface

Returns a sequential {@code Stream} containing a single element.

② In the .Stream () method returns an iterator used after divided to division Stream

/**
 * Returns a sequential {@code Stream} with this collection as its source.
 *
 * <p>This method should be overridden when the {@link #spliterator()}
 * method cannot return a spliterator that is {@code IMMUTABLE},
 * {@code CONCURRENT}, or <em>late-binding</em>. (See {@link #spliterator()}
 * for details.)
 *
 * @implSpec
 * The default implementation creates a sequential {@code Stream} from the
 * collection's {@code Spliterator}.
 *
 * @return a sequential {@code Stream} over the elements in this collection
 * @since 1.8
 */

Therefore, the results obtained ① and ② internal iteration is not the same.

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