Kotlin extensions for core and test now next to java code

This commit pulls down kotlin extensions for core and test into the
original java project instead of a separate project/artifact.

build.gradle

@@ -15,14 +15,16 @@
  */
 
 buildscript {
+  ext.kotlinVersion = '1.1.2-5'
   repositories {
 	maven { url "http://repo.spring.io/plugins-release" }
   }
   dependencies {
 	classpath 'org.springframework.build.gradle:propdeps-plugin:0.0.7',
 			'io.spring.gradle:spring-io-plugin:0.0.4.RELEASE',
 			'com.github.jengelman.gradle.plugins:shadow:1.2.0',
-			'org.asciidoctor:asciidoctorj-pdf:1.5.0-alpha.11'
+			'org.asciidoctor:asciidoctorj-pdf:1.5.0-alpha.11',
+			"org.jetbrains.kotlin:kotlin-gradle-plugin:${kotlinVersion}"
   }
 }
 
@@ -61,6 +63,7 @@ ext {
 
 configure(subprojects) { p ->
   apply plugin: 'java'
+  apply plugin: 'kotlin'
   apply plugin: 'jacoco'
   apply plugin: 'propdeps'
   apply plugin: 'osgi'
@@ -124,6 +127,14 @@ configure(subprojects) { p ->
 	targetCompatibility = 1.8
   }
 
+  compileKotlin {
+	kotlinOptions.jvmTarget = "1.8"
+  }
+
+  compileTestKotlin {
+	kotlinOptions.jvmTarget = "1.8"
+  }
+
   if (JavaVersion.current().isJava8Compatible()) {
 	compileTestJava.options.compilerArgs += "-parameters"
 	p.tasks.withType(Javadoc) {
@@ -190,6 +201,8 @@ project('reactor-core') {
 	//Optional Logging Operator
 	optional "org.slf4j:slf4j-api:$slf4jVersion"
 
+	optional("org.jetbrains.kotlin:kotlin-stdlib:${kotlinVersion}")
+
 	//Optional JDK 9 Converter
 	jsr166backport "io.projectreactor:jsr166:1.0.0.RELEASE"
 

reactor-core/src/main/java/reactor/core/publisher/MonoBridges.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2011-2017 Pivotal Software Inc, All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package reactor.core.publisher;
+
+import java.util.function.Function;
+
+import org.reactivestreams.Publisher;
+
+/**
+ * Utilities to avoid vararg array copying overhead when relaying vararg parameters
+ * to underlying Java methods from their corresponding Kotlin functions.
+ * <p>
+ * When <a href="https://youtrack.jetbrains.com/issue/KT-17043">this</a> issue is
+ * resolved, uses of these bridge methods can be removed.
+ *
+ * @author DoHyung Kim
+ * @since 3.1
+ */
+class MonoBridges {
+
+    static Mono<Void> when(Publisher<Void>[] sources) {
+        return Mono.when(sources);
+    }
+
+    static <R> Mono<R> when(Function<? super Object[], ? extends R> combinator, Mono<?>[] monos) {
+        return Mono.when(combinator, monos);
+    }
+
+    private MonoBridges() {
+        // Not to be instantiated
+    }
+}

reactor-core/src/main/kotlin/reactor/core/publisher/FluxExtensions.kt

@@ -0,0 +1,185 @@
+/*
+ * Copyright (c) 2011-2017 Pivotal Software Inc, All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package reactor.core.publisher
+
+import org.reactivestreams.Publisher
+import java.util.stream.Stream
+import kotlin.reflect.KClass
+
+
+/**
+ * Extension for transforming an [Iterator] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T> Iterator<T>.toFlux(): Flux<T> = toIterable().toFlux()
+
+/**
+ * Extension for transforming an [Iterable] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T> Iterable<T>.toFlux(): Flux<T> = Flux.fromIterable(this)
+
+/**
+ * Extension for transforming a [Sequence] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T> Sequence<T>.toFlux(): Flux<T> = Flux.fromIterable(object : Iterable<T> {
+    override fun iterator(): Iterator<T> = this@toFlux.iterator()
+})
+
+/**
+ * Extension for transforming a [Stream] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T> Stream<T>.toFlux(): Flux<T> = Flux.fromStream(this)
+
+/**
+ * Extension for transforming a [BooleanArray] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun BooleanArray.toFlux(): Flux<Boolean> = this.toList().toFlux()
+
+/**
+ * Extension for transforming a [ByteArray] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun ByteArray.toFlux(): Flux<Byte> = this.toList().toFlux()
+
+/**
+ * Extension for transforming a [ShortArray] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun ShortArray.toFlux(): Flux<Short> = this.toList().toFlux()
+
+/**
+ * Extension for transforming a [IntArray] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun IntArray.toFlux(): Flux<Int> = this.toList().toFlux()
+
+/**
+ * Extension for transforming a [LongArray] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun LongArray.toFlux(): Flux<Long> = this.toList().toFlux()
+
+/**
+ * Extension for transforming a [FloatArray] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun FloatArray.toFlux(): Flux<Float> = this.toList().toFlux()
+
+/**
+ * Extension for transforming a [DoubleArray] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun DoubleArray.toFlux(): Flux<Double> = this.toList().toFlux()
+
+/**
+ * Extension for transforming an [Array] to a [Flux].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T> Array<out T>.toFlux(): Flux<T> = Flux.fromArray(this)
+
+private fun <T> Iterator<T>.toIterable() = object : Iterable<T> {
+    override fun iterator(): Iterator<T> = this@toIterable
+}
+
+/**
+ * Extension for transforming an exception to a [Flux] that completes with the specified error.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T> Throwable.toFlux(): Flux<T> = Flux.error(this)
+
+/**
+ * Extension for [Flux.cast] providing a `cast<Foo>()` variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+inline fun <reified T : Any> Flux<*>.cast(): Flux<T> = cast(T::class.java)
+
+
+/**
+ * Extension for [Flux.doOnError] providing a [KClass] based variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T, E : Throwable> Flux<T>.doOnError(exceptionType: KClass<E>, onError: (E) -> Unit): Flux<T> =
+        doOnError(exceptionType.java, { onError(it) })
+
+/**
+ * Extension for [Flux.onErrorMap] providing a [KClass] based variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T, E : Throwable> Flux<T>.onErrorMap(exceptionType: KClass<E>, mapper: (E) -> Throwable): Flux<T> =
+        onErrorMap(exceptionType.java, { mapper(it) })
+
+/**
+ * Extension for [Flux.ofType] providing a `ofType<Foo>()` variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+inline fun <reified T : Any> Flux<*>.ofType(): Flux<T> = ofType(T::class.java)
+
+/**
+ * Extension for [Flux.onErrorResume] providing a [KClass] based variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T : Any, E : Throwable> Flux<T>.onErrorResume(exceptionType: KClass<E>, fallback: (E) -> Publisher<T>): Flux<T> =
+        onErrorResume(exceptionType.java, { fallback(it) })
+
+/**
+ * Extension for [Flux.onErrorReturn] providing a [KClass] based variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T : Any, E : Throwable> Flux<T>.onErrorReturn(exceptionType: KClass<E>, value: T): Flux<T> =
+        onErrorReturn(exceptionType.java, value)

reactor-core/src/main/kotlin/reactor/core/publisher/MonoExtensions.kt

@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2011-2017 Pivotal Software Inc, All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package reactor.core.publisher
+
+import java.util.concurrent.Callable
+import java.util.concurrent.CompletableFuture
+import kotlin.reflect.KClass
+
+
+/**
+ * Extension for transforming an object to a [Mono].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T> T.toMono(): Mono<T> = Mono.just(this)
+
+/**
+ * Extension for transforming an [CompletableFuture] to a [Mono].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T> CompletableFuture<T>.toMono(): Mono<T> = Mono.fromFuture(this)
+
+/**
+ * Extension for transforming an [Callable] to a [Mono].
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T> Callable<T>.toMono(): Mono<T> = Mono.fromCallable(this::call)
+
+/**
+ * Extension for transforming an exception to a [Mono] that completes with the specified error.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T> Throwable.toMono(): Mono<T> = Mono.error(this)
+
+/**
+ * Extension for [Mono.cast] providing a `cast<Foo>()` variant.
+ *
+ * @author Sebastien
+ * @since 3.1
+ */
+inline fun <reified T : Any> Mono<*>.cast(): Mono<T> = cast(T::class.java)
+
+/**
+ * Extension for [Mono.doOnError] providing a [KClass] based variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T, E : Throwable> Mono<T>.doOnError(exceptionType: KClass<E>, onError: (E) -> Unit): Mono<T> =
+        doOnError(exceptionType.java, { onError(it) })
+
+/**
+ * Extension for [Mono.onErrorMap] providing a [KClass] based variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T, E : Throwable> Mono<T>.onErrorMap(exceptionType: KClass<E>, mapper: (E) -> Throwable): Mono<T> =
+        onErrorMap(exceptionType.java, { mapper(it) })
+
+/**
+ * Extension for [Mono.ofType] providing a `ofType<Foo>()` variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+inline fun <reified T : Any> Mono<*>.ofType(): Mono<T> = ofType(T::class.java)
+
+/**
+ * Extension for [Mono.onErrorResume] providing a [KClass] based variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T : Any, E : Throwable> Mono<T>.onErrorResume(exceptionType: KClass<E>, fallback: (E) -> Mono<T>): Mono<T> =
+        onErrorResume(exceptionType.java, { fallback(it) })
+
+/**
+ * Extension for [Mono.onErrorReturn] providing a [KClass] based variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 3.1
+ */
+fun <T : Any, E : Throwable> Mono<T>.onErrorReturn(exceptionType: KClass<E>, value: T): Mono<T> =
+        onErrorReturn(exceptionType.java, value)