RxJava VS Vert.x

Compare RxJava vs Vert.x and see what are their differences.

RxJava

RxJava – Reactive Extensions for the JVM – a library for composing asynchronous and event-based programs using observable sequences for the Java VM. (by ReactiveX)

Vert.x

Vert.x is a tool-kit for building reactive applications on the JVM (by eclipse-vertx)
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RxJava Vert.x
8 22
45,692 12,613
0.4% 0.8%
8.4 9.4
2 days ago about 19 hours ago
Java Java
Apache License 2.0 GNU General Public License v3.0 or later
The number of mentions indicates the total number of mentions that we've tracked plus the number of user suggested alternatives.
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.

RxJava

Posts with mentions or reviews of RxJava. We have used some of these posts to build our list of alternatives and similar projects. The last one was on 2022-01-07.
  • What are the most common used (3rd party) libraries and frameworks used in Android development?
    30 projects | reddit.com/r/androiddev | 7 Jan 2022
    Concurrency: Kotlin coroutines for general use, Rx or Flow for reactive programming (you can technically use Rx for regular concurrency as well, but not really what it's meant for)
  • Notification when item add to a ListView
    1 project | reddit.com/r/javahelp | 1 Nov 2021
    If you're just looking at making a service call on a regular interval and notifying the user when there's an actual change in data, you can also look into RxJava https://github.com/ReactiveX/RxJava. From here you can "subscribe" to your service call, and then every time you make your service call you can have it look for changes compared to the previous emission .distinctUntilChanged() and then only notify it's subscribers when it notices an actual change. From there you can trigger a local notification and push to a LiveData (assuming MVVM) or otherwise update the UI to match as well.
  • Crash on update
    1 project | reddit.com/r/NewPipe | 14 Oct 2021
    ``` io.reactivex.rxjava3.exceptions.OnErrorNotImplementedException: The exception was not handled due to missing onError handler in the subscribe() method call. Further reading: https://github.com/ReactiveX/RxJava/wiki/Error-Handling | java.lang.IllegalStateException: Migration didn't properly handle: feed_group(org.schabi.newpipe.database.feed.model.FeedGroupEntity). Expected: TableInfo{name='feed_group', columns={name=Column{name='name', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='null'}, uid=Column{name='uid', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='null'}, icon_id=Column{name='icon_id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}, sort_order=Column{name='sort_order', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}}, foreignKeys=[], indices=[Index{name='index_feed_group_sort_order', unique=false, columns=[sort_order]}]} Found: TableInfo{name='feed_group', columns={uid=Column{name='uid', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='null'}, name=Column{name='name', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='null'}, icon_id=Column{name='icon_id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}, sort_order=Column{name='sort_order', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='0'}}, foreignKeys=[], indices=[]} at io.reactivex.rxjava3.internal.functions.Functions$OnErrorMissingConsumer.accept(Functions.java:717) at io.reactivex.rxjava3.internal.functions.Functions$OnErrorMissingConsumer.accept(Functions.java:714) at io.reactivex.rxjava3.internal.subscribers.LambdaSubscriber.onError(LambdaSubscriber.java:79) at io.reactivex.rxjava3.internal.operators.flowable.FlowableObserveOn$BaseObserveOnSubscriber.checkTerminated(FlowableObserveOn.java:209) at io.reactivex.rxjava3.internal.operators.flowable.FlowableObserveOn$ObserveOnSubscriber.runAsync(FlowableObserveOn.java:394) at io.reactivex.rxjava3.internal.operators.flowable.FlowableObserveOn$BaseObserveOnSubscriber.run(FlowableObserveOn.java:176) at io.reactivex.rxjava3.android.schedulers.HandlerScheduler$ScheduledRunnable.run(HandlerScheduler.java:123) at android.os.Handler.handleCallback(Handler.java:938) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:223) at android.app.ActivityThread.main(ActivityThread.java:7665) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:594) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947) Caused by: java.lang.IllegalStateException: Migration didn't properly handle: feed_group(org.schabi.newpipe.database.feed.model.FeedGroupEntity). Expected: TableInfo{name='feed_group', columns={name=Column{name='name', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='null'}, uid=Column{name='uid', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='null'}, icon_id=Column{name='icon_id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}, sort_order=Column{name='sort_order', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}}, foreignKeys=[], indices=[Index{name='index_feed_group_sort_order', unique=false, columns=[sort_order]}]} Found: TableInfo{name='feed_group', columns={uid=Column{name='uid', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='null'}, name=Column{name='name', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='null'}, icon_id=Column{name='icon_id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}, sort_order=Column{name='sort_order', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='0'}}, foreignKeys=[], indices=[]} at androidx.room.RoomOpenHelper.onUpgrade(RoomOpenHelper.java:103) at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper$OpenHelper.onUpgrade(FrameworkSQLiteOpenHelper.java:177) at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:416) at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:316) at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper$OpenHelper.getWritableSupportDatabase(FrameworkSQLiteOpenHelper.java:145) at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper.getWritableDatabase(FrameworkSQLiteOpenHelper.java:106) at androidx.room.RoomDatabase.inTransaction(RoomDatabase.java:622) at androidx.room.RoomDatabase.assertNotSuspendingTransaction(RoomDatabase.java:399) at androidx.room.RoomDatabase.query(RoomDatabase.java:442) at androidx.room.util.DBUtil.query(DBUtil.java:83) at org.schabi.newpipe.database.feed.dao.FeedDAO_Impl$7.call(FeedDAO_Impl.java:285) at org.schabi.newpipe.database.feed.dao.FeedDAO_Impl$7.call(FeedDAO_Impl.java:282) at io.reactivex.rxjava3.internal.operators.maybe.MaybeFromCallable.subscribeActual(MaybeFromCallable.java:47) at io.reactivex.rxjava3.core.Maybe.subscribe(Maybe.java:5330) at io.reactivex.rxjava3.internal.operators.flowable.FlowableFlatMapMaybe$FlatMapMaybeSubscriber.onNext(FlowableFlatMapMaybe.java:131) at io.reactivex.rxjava3.internal.operators.flowable.FlowableObserveOn$ObserveOnSubscriber.runAsync(FlowableObserveOn.java:402) at io.reactivex.rxjava3.internal.operators.flowable.FlowableObserveOn$BaseObserveOnSubscriber.run(FlowableObserveOn.java:176) at io.reactivex.rxjava3.internal.schedulers.ExecutorScheduler$ExecutorWorker$BooleanRunnable.run(ExecutorScheduler.java:322) at io.reactivex.rxjava3.internal.schedulers.ExecutorScheduler$ExecutorWorker.runEager(ExecutorScheduler.java:287) at io.reactivex.rxjava3.internal.schedulers.ExecutorScheduler$ExecutorWorker.run(ExecutorScheduler.java:248) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641) at java.lang.Thread.run(Thread.java:923)
  • When consuming from a reactive stream is it more like a literal stream where items in the stream ay go by and not get consumed while you're busy, or is it more like a queue?
    2 projects | reddit.com/r/learnjava | 3 Aug 2021
    In big words, kafka and rxJava are 2 different things, with kafka you transport data, produce and consume messages, then you can process them however you want. Rx java helps you write asynchronous code and it's no queue/topic related. You can read more here
  • MVVM Architecture On HarmonyOS Using Retrofit And RxJava
    3 projects | reddit.com/r/HuaweiDevelopers | 29 Mar 2021
  • Backpressure in Reactive Systems
    3 projects | dev.to | 14 Mar 2021
    This post provides information on backpressure in general and how RxJava (v3), Project Reactor and Kotlin's Coroutines handle it.
  • JavaFX - Mulithreading Query so the UI doesn't stuck
    1 project | reddit.com/r/JavaFX | 2 Feb 2021
    It's actually very easy to move things off the JavaFX thread. Here's a few options: - Plain old threads - ExecutorService (I would start here!) - RxJava (Look at suscribeOn and observerOn methods)
  • Functional Programming in Java, Explained
    2 projects | dev.to | 14 Dec 2020
    Both of the most popular Java Reactive libraries, RxJava and Reactor, are based on Java 8 Streams API, which means they also use functional interfaces in their code.

Vert.x

Posts with mentions or reviews of Vert.x. We have used some of these posts to build our list of alternatives and similar projects. The last one was on 2022-01-02.
  • [2022] Vert.x vs Spring
    1 project | reddit.com/r/Kotlin | 10 Jan 2022
    That being said, between the two you mentioned, spring is probably the more popular framework because of the magic annotation processing it provides if you're into that. Otherwise vertx seems like a good framework if you want something light, not sure which large projects are using it out there though short of looking at their site.
  • Switching to Java
    5 projects | reddit.com/r/java | 2 Jan 2022
    Something like Vert.x would be much close to node.js (it's inspired by it!) and it's pretty easy to use. I would also at least read about the following frameworks before deciding on which one to try a bit more:
  • Native-image with Quarkus
    3 projects | dev.to | 12 Dec 2021
    Because the developers of Quarkus also worked on Vert.x, the former also offers a plugin that integrates the latter. Vert.x is full reactive and provides the concept of routes. With Quarkus, you can annotate methods to mark them as routes. One can migrate the above code to routes:
  • Async I/O for Dummies (2018)
    2 projects | news.ycombinator.com | 5 Dec 2021
    Backend newb, here. I have a dumb question - can someone give me a summary, or blog post to a summary, of the pros /cons of async versus threads?

    One thing I have been using as a way of understanding hi-perf backends is analyzing why the vert.x framework [1] (and its underlying server, netty) does so well on benchmarks [2], but as newb, I do not think I would get a lot form that exercise without a little hand holding.

    [1] https://vertx.io/

    [2] Ad of today, #28 on tech empower benchmarks - https://www.techempower.com/benchmarks/

  • Java Equivalent of Express.js for REST
    8 projects | reddit.com/r/java | 14 Oct 2021
    Came here to say this. Vert.x was inspired by Node+Express. It was even originally named NodeX.
    8 projects | reddit.com/r/java | 14 Oct 2021
    Vert.x
  • GraalVM + Typescript + Quarkus !??
    2 projects | reddit.com/r/java | 22 Sep 2021
    Check out ES4X. It's JS and TS bindings for GraalJS for Vert.x. Vert.x is the basis for Quarkus, so this is definitely possible.
  • Yet another ode to Vert.x, or how to write a performance-wise expiring map in less than 100 lines of code.
    1 project | dev.to | 22 Sep 2021
    I've been working with the Vert.x framework for more than 4 years but I won't stop being excited how simple, lightweight and elegant it is (especially the event loop thread model). In this blog post I will tell you how we implemented PeriodicallyExpiringHashMap data structure in less than 100 lines of code. But first let me give you a bit of a context about why do we need it.
  • The Reactive Manifesto
    1 project | news.ycombinator.com | 3 Sep 2021
  • Advice on Multithreading Approach
    2 projects | reddit.com/r/javahelp | 30 Aug 2021
    You might want to consider a lightweight reactive library like Akka or Vert.x which will make more efficient use of threads, and takes the work away of having to write a concurrent, distributed application, so you can just focus on writing your poker app.

What are some alternatives?

When comparing RxJava and Vert.x you can also consider the following projects:

Akka - Build highly concurrent, distributed, and resilient message-driven applications on the JVM

Reactor

Lagom - Reactive Microservices for the JVM

EventBus - Event bus for Android and Java that simplifies communication between Activities, Fragments, Threads, Services, etc. Less code, better quality.

Micronaut - Micronaut Application Framework

Zuul - Zuul is a gateway service that provides dynamic routing, monitoring, resiliency, security, and more.

Ehcache - Ehcache 3.x line

Quasar - Fibers, Channels and Actors for the JVM

javalin - A simple and modern Java and Kotlin web framework

Redisson - Redisson - Redis Java client with features of In-Memory Data Grid. Over 50 Redis based Java objects and services: Set, Multimap, SortedSet, Map, List, Queue, Deque, Semaphore, Lock, AtomicLong, Map Reduce, Publish / Subscribe, Bloom filter, Spring Cache, Tomcat, Scheduler, JCache API, Hibernate, MyBatis, RPC, local cache ...

Reactive Streams - Reactive Streams Specification for the JVM

Jooby - The modular web framework for Java and Kotlin