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ixjava Maven Central

Iterable Extensions for Java, the dual of RxJava. Originally implemented in the Reactive4Java framework, now standalone; no dependencies on any reactive library.

The aim is to provide, lazily evaluated, pull-based datastream support with the same naming as in RxJava mainly for the pre-Java-8 world. The Stream API in Java 8 is not exactly the same thing because Streams can be only consumed once while Iterables can be consumed many times. Google Guava features a lot of Iterable operators, plus now they have the FluentIterable with similar setup but far less operators available.

This branch starts from scratch by reimplementing ix.Ix and all of its operators based on the +5 year experience with reactive and interactive dataflows.




dependencies {
    implementation 'com.github.akarnokd:ixjava:1.0.0'

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The main (and only) entry point is the class ix.Ix which features a bunch of static factory methods:

List<Integer> list = Arrays.asList(1, 2, 3, 4, 5);

Ix<Integer> seq = Ix.from(list);

Now we can apply instance methods on the seq sequence, just like in RxJava. Not all operators are available though due to the synchronous-pull nature of IxJava.

.map(v -> v + 1)
.filter(v -> v % 2 == 0)
.flatMap(v -> Ix.fromArray(v * 10, v * 100)))

Since Ix implements Iterable, you can use the for-each loop to consume it:

for (Integer v : Ix.fromArray(5, 10).skip(1).concatWith(Ix.just(20))) {
    System.out.println("Value: " + v);

For further details on the possibilities, please study the javadoc of Ix.