rx-java set up
Gradle
compile 'io.reactivex:rxjava2:rxjava:2.1.1'
Maven
<dependency>
    <groupId>io.reactivex.rxjava2</groupId>
    <artifactId>rxjava</artifactId>
    <version>2.1.1</version>
</dependency>
Ivy
<dependency org="io.reactivex.rxjava2" name="rxjava" rev="2.1.1" />
Snapshots from JFrog
repositories {
maven { url 'https://oss.jfrog.org/libs-snapshot' }
}
dependencies {
    compile 'io.reactivex:rxjava:2.0.0-SNAPSHOT'
}
If you need to download the jars instead of using a build system, create a Maven pom file like this with the desired version:
<?xml version="1.0"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.netflix.rxjava.download</groupId>
    <artifactId>rxjava-download</artifactId>
    <version>1.0-SNAPSHOT</version>
    <name>Simple POM to download rxjava and dependencies</name>
    <url>http://github.com/ReactiveX/RxJava</url>
    <dependencies>
        <dependency>
            <groupId>io.reactivex</groupId>
            <artifactId>rxjava</artifactId>
            <version>2.0.0</version>
            <scope/>
        </dependency>
    </dependencies>
</project>
Then execute:
$ mvn -f download-rxjava-pom.xml dependency:copy-dependencies
That command downloads rxjava-*.jar and its dependencies into ./target/dependency/.
You need Java 6 or later.