Mixins : Streamable

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All new develpoment on cyclops occurs in cyclops-react. Older modules are still available in maven central.

Streamable

com.aol.cyclops.lambda.api.Streamable represents a datastructure that can generate a Stream. Replayable Streamables can be lazily constructed from traverse-once Java 8 Streams, or Collections and more.

Objects can be coerced to Streamable, if they don't implement it already, via

• AsStreamable.asStreamable
• As.asStreamable

When stream() is called on coerced Streamables

• If the coerced Object is itself a Stream, a new copy will be returned each time.
• If the Object is an iterable a new Stream will be generated from that
• Otherwise, if the object has a stream() or toStream() method it will be called using JDK InvokeDynamic functionality
• If the Object does not have a stream() or toStream() method, it will be coereced to Decomposable which provides a mechanism to create an Iterable for the Object (from it's fields). The Stream will be generated via the Iterable unapply() method.

Example : coercing a Stream to Streamable

A Stream can be coerced to a Stremable, and stream() invoked multiple times over the same Streamable instance -

       Stream<Integer> stream = Stream.of(1,2,3,4,5);
       Streamable<Integer> streamable = As.<Integer>asStreamable(stream);
       List<Integer> result1 = streamable.stream().map(i->i+2).collect(Collectors.toList());
       List<Integer> result2 = streamable.stream().map(i->i+2).collect(Collectors.toList());
       List<Integer> result3 = streamable.stream().map(i->i+2).collect(Collectors.toList());
		
	assertThat(result1,equalTo(Arrays.asList(3,4,5,6,7)));
	assertThat(result1,equalTo(result2));
	assertThat(result1,equalTo(result3));

Example : coercing a List to Streamable

     List<Integer> result = As.<Integer>asStreamable(Arrays.asList(1,2,3)).stream().map(i->i+2).collect(Collectors.toList());
		
    assertThat(result,equalTo(Arrays.asList(3,4,5)));