Reactor-Extra

The reactor-extra artifact contains additional operators and utilities that are for users of reactor-core with advanced needs, or incubating operators.

As this is a separate artifact, you need to explicitly add it to your build. The following example shows how to do so in Gradle:

dependencies {
     compile 'io.projectreactor:reactor-core'
     compile 'io.projectreactor.addons:reactor-extra' (1)
}
1 Add the reactor extra artifact in addition to core. See Getting Reactor for details about why you do not need to specify a version if you use the BOM, usage in Maven, and other details.

1. TupleUtils and Functional Interfaces

The reactor.function package contains functional interfaces that complement the Java 8 Function, Predicate, and Consumer interfaces, for three to eight values.

TupleUtils offers static methods that act as a bridge between lambdas of these functional interfaces to a similar interface on the corresponding Tuple.

This lets you easily work with independent parts of any Tuple, as the following example shows:

.map(tuple -> {
  String firstName = tuple.getT1();
  String lastName = tuple.getT2();
  String address = tuple.getT3();

  return new Customer(firstName, lastName, address);
});

You can rewrite the preceding example as follows:

.map(TupleUtils.function(Customer::new)); (1)
1 (as Customer constructor conforms to Function3 functional interface signature)

2. Math Operators With MathFlux

The reactor.math package contains a MathFlux specialized version of Flux that offers mathematical operators, including max, min, sumInt, averageDouble, and others.

3. Schedulers

Reactor-extra comes with the ForkJoinPoolScheduler (in the reactor.scheduler.forkjoin package): it uses the Java ForkJoinPool to execute tasks.