Jersey Reactive Client - JSR-166e, pre-Java 8, (CompletableFuture) provider.
'org.glassfish.jersey.ext.rx:jersey-rx-client-jsr166e:2.21'
<dependency>
<groupId>org.glassfish.jersey.ext.rx</groupId>
<artifactId>jersey-rx-client-jsr166e</artifactId>
<version>2.21</version>
</dependency>
<dependency org="org.glassfish.jersey.ext.rx" name="jersey-rx-client-jsr166e" rev="2.21"/>
"org.glassfish.jersey.ext.rx", "jersey-rx-client-jsr166e", "2.21"